US20120222730A1 - Tandem solar cell with improved absorption material - Google Patents
Tandem solar cell with improved absorption material Download PDFInfo
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- US20120222730A1 US20120222730A1 US13/037,798 US201113037798A US2012222730A1 US 20120222730 A1 US20120222730 A1 US 20120222730A1 US 201113037798 A US201113037798 A US 201113037798A US 2012222730 A1 US2012222730 A1 US 2012222730A1
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- H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
- H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
- H01L31/0264—Inorganic materials
- H01L31/032—Inorganic materials including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312
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- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
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- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
- H01L31/075—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PIN type
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
- H01L31/078—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier including different types of potential barriers provided for in two or more of groups H01L31/062 - H01L31/075
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- H—ELECTRICITY
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- H—ELECTRICITY
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- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
- H01L31/20—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof such devices or parts thereof comprising amorphous semiconductor materials
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
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- Y02E10/548—Amorphous silicon PV cells
Definitions
- Solar cells employ photovoltaic cells to generate current flow. Photons in sunlight hit a solar cell or panel and are absorbed by semiconducting materials, such as silicon. Electrons gain energy allowing them to flow through the material to produce electricity.
- the photon When a photon hits silicon, the photon may be transmitted through the silicon, the photon can reflect off the surface, or the photon can be absorbed by the silicon, if the photon energy is higher than the silicon band gap value. This generates an electron-hole pair and sometimes heat, depending on the band structure.
- a photon When a photon is absorbed, its energy is given to an electron in a crystal lattice. Electrons in the valence band may be excited into the conduction band, where they are free to move within the semiconductor. The bond that the electron(s) were a part of form a hole. These holes can move through the lattice creating mobile electron-hole pairs.
- a solar cell may be described in terms of a fill factor (FF).
- FF is a ratio of the maximum power point (P m ) divided by open circuit voltage (V oc ) and short circuit current (J sc ):
- the fill factor is directly affected by the values of a cell's series and shunt resistance. Increasing the shunt resistance (R sh ) and decreasing the series resistance (Rs) will lead to a higher fill factor, thus resulting in greater efficiency, and pushing the cells output power closer towards its theoretical maximum. The increased efficiency of photovoltaic devices is of utmost importance in the current energy environment.
- tandem cells have been employed where a first solar cell is integrated with a second solar cell.
- Such cells typically employ a microcrystalline Silicon based bottom cell, which includes microcrystalline Silicon for a p-doped layer, an intrinsic layer and an n-doped layer for the cell.
- microcrystalline Silicon based bottom cell which includes microcrystalline Silicon for a p-doped layer, an intrinsic layer and an n-doped layer for the cell.
- the growth rate for high quality microcrystalline cells may be about 2-3 Angstroms/sec for a 1.5 micron thickness, and can take 1-2 hours to grow the microcrystalline Silicon. This results in higher cost.
- a top cell in such device also includes a form of Silicon, current sharing between the top and bottom cells is excessive, e.g., Jsc for the tandem device is often less than Jsc for an individual cell.
- Thin-film materials of the type Cu(In,Ga)(S,Se) 2 include rare indium metal, which is expected to be of high cost and short supply in future large-scale photovoltaic device production—an issue which is further exacerbated by the growing indium consumption for thin film display production.
- Other materials such as Cu 2 S and CdTe have also been proposed as absorbers but while Cu 2 S suffers from low stability in devices, rare tellurium and toxic cadmium limits CdTe usage.
- a photosensitive device and method includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween.
- a bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer therebetween.
- the bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide.
- a photosensitive device includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween.
- a bottom cell has an N-type layer, a P-type layer and a bottom intrinsic layer therebetween.
- the bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu 2-x Zn 1+y Sn(S 1-z Se z ) 4+q wherein 0 ⁇ x ⁇ 1; 0 ⁇ y ⁇ 1; 0 ⁇ z ⁇ 1; ⁇ 1 ⁇ q ⁇ 1, wherein z is controlled to adjust a band gap of the bottom cell to be lower than a band gap of the top cell.
- a method for fabrication of a tandem photovoltaic device includes forming a bottom cell having an N-type layer, a P-type layer and a bottom intrinsic layer therebetween, wherein the bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide; and forming a top cell over the bottom cell to form a tandem cell, the top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween.
- FIG. 1 is a cross-sectional view of an illustrative tandem cell device structure in accordance with the present principles
- FIG. 2A is a plot of external quantum efficiency (EQE) versus wavelength for top and bottom cells of a conventional tandem cell
- FIG. 2B is a plot of external quantum efficiency (EQE) versus wavelength for top and bottom cells of a tandem cell in accordance with the present principles.
- FIG. 3 is a flow diagram showing a method for fabricating a tandem cell in accordance with the present principles.
- a new tandem solar cell device structure is provided that increases productivity and performance over conventional cells which typically employ microcrystalline silicon bottom cells. Greater efficiency is provided at least in part by less current sharing between top and bottom cells in the tandem structure. Further, the present embodiments provide tandem cells composed of materials which are rapidly grown or applied with high quality. This makes the present embodiments more cost effective in addition to other advantages.
- a tandem cell is fabricated having a one cell fabricated using a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu 2-x Zn 1+y Sn(S 1-z Se z ) 4+q wherein 0 ⁇ x ⁇ 1; 0 ⁇ y ⁇ 1; 0 ⁇ z ⁇ 1; ⁇ 1 ⁇ q ⁇ 1.
- Cu 2 ZnSn(S, Se) 4 CZTS or CZTSe
- CZTS has many benefits. It is low cost and environmentally harmless being fabricated using naturally abundant materials.
- CZTS provides good optical properties and has a band-gap energy from approximately 1 to 1.5 eV depending on the degree of substitution of S with Se and a large absorption coefficient in the order of 10 4 cm ⁇ 1 . Eliminating the reliance on rare indium metal (also heavily consumed by one of the fastest growing industries—thin film displays) opens the possibility of almost limitless material supply for production capacities well above 100 GWp/year.
- the efficiency of CZTS e.g., in the 10% range, can be maximized by making a tandem cell with amorphous silicon having higher band gap and thus allowing more effective light harvesting across the solar spectrum.
- the devices described here may be part of a circuit and include a design for an integrated circuit chip, a photovoltaic device, a photosensitive circuit, etc.
- the design may be created in a graphical computer programming language, and stored in a computer storage medium (such as a disk, tape, physical hard drive, or virtual hard drive such as in a storage access network).
- the designer may transmit the resulting design by physical means (e.g., by providing a copy of the storage medium storing the design) or electronically (e.g., through the Internet) to entities, directly or indirectly.
- the stored design may be converted into the appropriate format (e.g., GDSII) for the fabrication of photolithographic masks, which typically include multiple copies of the design in question that are to be formed on a substrate.
- the photolithographic masks are utilized to define areas of the substrate (and/or the layers thereon) to be etched or otherwise processed.
- the methods as described herein may be used in the fabrication of integrated circuit chips, a photovoltaic device, a photosensitive circuit, etc.
- the device may be integrated with other chips, discrete circuit elements, and/or other signal processing devices as part of either (a) an intermediate product, such as a printed wiring board, or (b) an end product.
- the end product can be any product that includes devices, ranging from toys and other low-end applications to advanced computer products having a display, a keyboard or other input device, and a central processor.
- FIG. 1 an illustrative tandem photovoltaic structure 100 is illustratively depicted in accordance with one embodiment.
- the photovoltaic structure 100 may be employed in solar cells, light sensors, photosensitive devices or other photovoltaic applications.
- the embodiment depicted in FIG. 1 includes two cells 102 and 104 stacked in tandem.
- a top cell 102 includes a first doped layer 106 which may include amorphous silicon (e.g., a-Si:H) or other suitable materials for thin film solar cells.
- the first doped layer 106 includes an N-type (n+) doping.
- a layer 108 may include a transparent electrode (transparent conducting oxide (TCO)). The first layer 106 provides a first doping layer for the top cell 102 .
- An intrinsic layer 110 includes a material compatible with layer 106 and a layer 112 .
- the intrinsic layer 110 is undoped.
- layer 110 includes amorphous silicon (a-Si:H) although other materials may also be employed.
- the intrinsic layer 110 may have a thickness of between about 100 to 300 nm.
- Layer 112 has an opposite polarity relative to the layer 106 (e.g., if layer 106 is N-type then layer 112 is P-type or vice versa).
- layer 112 is a P-type material and layer 106 is an N-type material.
- layer 112 may include a P-type (p+) microcrystalline silicon ( ⁇ c-Si:H) layer.
- Layer 112 is preferably thin, e.g., 1 nm to about 10 nm, and more preferably around 5 nm. Layer 112 forms a second doped layer of the top cell 102 .
- the top cell 102 is preferably formed to have band gap materials that have a higher band gap than the materials in bottom cell 104 .
- Layers 106 , 110 and 112 form the top cell 102 and layers 114 , 116 , and 120 form the bottom cell 104 to provide the double junction device 100 .
- the tandem cells 102 and 104 are configured such that light/radiation passing through the top cell 102 has a high likelihood of being absorbed in the bottom cell 104 .
- hydrogen plasma may be applied on layer 114 to enhance the crystallinity of the subsequently grown layer 112 on layer 114 so that conductivity of the tunnel junction can be improved.
- the bottom cell 104 employs a layer 120 on a substrate 122 .
- the layer 120 may include molybdenum although other high work-function materials may be employed (e.g., Pt, Au, etc.).
- the substrate 122 may include glass or other inexpensive substrates, such as metal, plastic, etc.
- the layer 120 provides a metal contact while layer 114 is an N-type material (e.g., n-CdS).
- Layer 120 (e.g., Mo layer) can be thicker than layer 114 to enable sufficient conductivity for adequate series resistance.
- the layer 114 may include CdS or other materials that serve as an N-type layer.
- Layer 116 includes a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu 2-x Zn 1+y Sn(S 1-z Se z ) 4+q wherein 0 ⁇ x ⁇ 1; 0 ⁇ y ⁇ 1; 0 ⁇ z ⁇ 1; ⁇ 1 ⁇ q ⁇ 1.
- the Cu—Zn—Sn-containing chalcogenide such as a Cu 2 ZnSn(S,Se) 4 (CZTS) based thin film, serves as a P-type material.
- the CZTS film has a thickness of between about 0.2 to 4.0 microns and more preferably about 2 microns.
- Layer 116 may be formed by painting, sputtering, electroplating, spin coating or other simple coating processes. The process of forming layer 116 is reduced to a few minutes or less from the hours required in forming a microcrystalline silicon layer in conventional
- Layer 114 is preferably thin, e.g., 1 nm to about 10 nm, more preferably around 5 nm.
- the layer 114 provides an N-type layer for the bottom cell 104 .
- the intrinsic layer 116 contacts layer 114 and layer 120 .
- the intrinsic layer 116 is undoped or slightly p-doped.
- intrinsic layer 116 includes CZTS (or CZTS with some Se substituted for S) which provides a band gap (E g ) from about 1 to 1.5 eV. It is desirable that the band gap of the intrinsic layer 110 of the top cell 102 be greater than the band gap of the bottom cell 104 .
- Layer 120 forms a bottom electrode of the bottom cell 104 .
- the deposition sequence can be completely opposite for a superstrate configuration (e.g., where light instead comes from the substrate 122 ).
- a top a-Si:H or a-SiC:H cell is deposited on top of a TCO/glass substrate ( 122 ).
- the bottom cell (with CZTS) is formed by forming a p-type tunnel junction on top of the top intrinsic layer of the top cell. Molybdenum would be deposited for the electrode, the CZTS absorber is formed and then capped with CdS.
- the CZTS process temperature should not exceed ⁇ 250 degrees C. since hydrogen in a-Si:H starts being evaporated out such that there is no more H passivation on broken bonds.
- Tandem cell device 100 is fabricated to maximize V OC and improve current matching between each junction. Multiple junctions are formed together so that the V OC of each junction is cumulatively added resulting in a high V OC for the multi-junction device due to the tandem cells.
- the J SC of the tandem cell device 100 is controlled by a single junction device, i.e., the device with the lowest J SC .
- it is desirable that any radiation that passes through the top cell 102 is absorbed in the bottom cell 104 (or middle cells if available). This is achieved by providing energy gap splitting (E g splitting). For example, the top cell 102 has higher band gap materials and receives light first.
- E g splitting energy gap splitting
- the light spectra that is not absorbed at the top cell 102 enters the bottom cell 104 .
- a larger band gap difference between two different junctions is better to prevent the light spectra from being shared between the junctions to maximize photocurrent.
- Energy gap splitting permits the absorption of radiation with different energies between the cells. Since the band gap of the top cell 102 is maintained at a higher level, the lower level cell ( 104 ) or cells are designed to have a lower band gap. In this way, the lower cells have a higher probability of absorbing transmitted radiation, and the entire tandem cell becomes more efficient since there are fewer photon energy levels shared between the layered cells. This results in increased probability of absorbing light passing through to the bottom cell 104 hence increasing the current in the bottom cell 104 , increasing J SC .
- the tandem device 100 may include at least one middle cell having an N-type layer, a P-type layer and a middle intrinsic layer therebetween which preferably includes a band gap energy between that of the top intrinsic layer and the bottom intrinsic layer.
- FIG. 2A a plot of external quantum efficiency (EQE) versus wavelength is shown for a conventional thin film silicon tandem cell.
- the tandem cell in FIG. 2A includes an amorphous silicon top cell and a microcrystalline silicon bottom cell.
- Plot 202 shows the top cell response
- plot 204 shows the bottom cell response for the microcrystalline silicon bottom cell over a wavelength range of 350 -1200 nm.
- FIG. 2B a plot of external quantum efficiency (EQE) versus wavelength is shown for a tandem cell in accordance with the present principles.
- the tandem cell in FIG. 2B includes an amorphous silicon top cell and a CZTS bottom cell.
- Plot 206 shows the top cell response, which is the same response as in FIG. 2A since the structure is the same for the top cell in plots 202 and 206 .
- a plot 208 shows the bottom cell response for the CZTS bottom cell over a wavelength range of 350 -1200 nm. Note that there significantly less wavelength overlap between the top cell plot 206 and the bottom cell plot 208 than in FIG. 2A . This translates to a greater amount of radiation absorption with less competition for the same wavelength light between cells.
- EQE is a quantity defined for a photosensitive device as the percentage of photons hitting the photoreactive surface that will produce an electron-hole pair (measurement of the device's electrical sensitivity to light at a certain wavelength). Since the energy of a photon is inversely proportional to its wavelength, EQE is measured over a range of different wavelengths to characterize a device's efficiency at each photon energy.
- the quantum efficiency of a solar cell gives information on the current that a given cell will produce when illuminated by a particular wavelength. If the quantum efficiency is integrated (summed) over the whole solar electromagnetic spectrum (area under the curve), the current that a cell will produce when exposed to the solar spectrum can be determined.
- the area under the EQE curve is significantly larger for the bottom cell with the CZTS in FIG. 2B .
- the plot rises to almost 1.0 at a wavelength of about 600 nm and is significantly higher over the entire spectrum as compared with plot 204 in FIG. 2A .
- EQE is the current obtained outside the device per incoming photon.
- EQE therefore depends on both the absorption of light and the collection of charge. Once a photon has been absorbed and has generated an electron-hole pair, these charges need to be separated and collected at the junction.
- Table I shows illustrative data for different device types. Table I includes open circuit voltage (Voc), short circuit current (Jsc), fill factor (FF) and Efficiency.
- Voc Jsc FF Efficiency Device Type (V) (mA/cm 2 ) (%) (%) (%) (%) Conventional a-Si/ ⁇ c-Si 1.4 12 73 12.3 Tandem a-Si/CZTS 1.4 15 ⁇ 16 73 15 ⁇ 16
- Single cell devices include efficiencies in the 9% range. Even a stand-alone CZTS device has a measured efficiency of about 9.6%.
- the conventional a-Si/ ⁇ -Si tandem cell provides an efficiency of about 12.3%.
- the tandem a-Si/CZTS in accordance with the present principles provides an expected efficiency of about 15-16% representing a significant gain in efficiency with lower production costs and lower material costs.
- a bottom cell is formed.
- the bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer formed therebetween.
- the bottom cell may be formed on a substrate, such as a glass substrate or the like.
- the bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu 2-x Zn 1+y Sn(S 1-z Se z ) 4+q wherein 0 ⁇ x ⁇ 1; 0 ⁇ y ⁇ 1; 0 ⁇ z ⁇ 1; ⁇ 1 ⁇ q ⁇ 1.
- the bottom cell preferably includes molybdenum as a back contact layer formed on a glass substrate, although other high work-function metals may be employed (e.g., Pt, Au, etc.).
- the bottom cell preferably includes a layer of cadmium sulfide as the N-type layer, although other N-type layers can also be employed, including, e.g., ZnS, Zn(O,S) (zinc oxysulfide), In 2 S 3 and ZnO.
- An example preparation of a Cu 2 ZnSn(S,Se) 4 film by ink (slurry) spin coating includes the following. All operations were performed in a nitrogen-filled glove box.
- the deposition solution was prepared in two parts in glass vials under magnetic stirring: Part A 1 was formed by dissolving Cu 2 S, 0.573 g and sulfur, 0.232 g in 3 ml of hydrazine and part B 1 was formed by mixing SnSe, 0.790 g, Se, 1.736g and Zn, 0.32 g with 7 ml of hydrazine. After 3 days under magnetic stirring, solution A 1 had an orange transparent aspect, while B 1 was dark green and opaque. Solutions A 1 and B 1 were mixed (C 1 ) before deposition.
- Films were deposited on soda lime glass substrates coated with 700 nm molybdenum by spin coating at 800 rpm and heated at 540° C. for 2 minutes. The coating and heating cycle were repeated 5 times before a final anneal was carried out for 10 minutes.
- z is controlled during formation to adjust a band gap of the bottom cell.
- the tandem cell in accordance with the present principles has a band gap of the bottom cell intrinsic layer controlled to be lower than a band gap of the top cell.
- the optical band gap may be tuned from approximately 1 to 1.5 eV by controlled substitution of the sulfur with selenium.
- processing is continued to complete the device.
- the N-type and P-type layer may be switched relative to each intrinsic layer.
- the top cell may be fanned first followed by the bottom cell.
- additional cells e.g., middle cells
Abstract
A photosensitive device and method includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween. A bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer therebetween. The bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide.
Description
- 1. Technical Field
- The present invention relates to solar cells and more particularly to a tandem solar cell device and method to achieve greater collection efficiency.
- 2. Description of the Related Art
- Solar cells employ photovoltaic cells to generate current flow. Photons in sunlight hit a solar cell or panel and are absorbed by semiconducting materials, such as silicon. Electrons gain energy allowing them to flow through the material to produce electricity.
- When a photon hits silicon, the photon may be transmitted through the silicon, the photon can reflect off the surface, or the photon can be absorbed by the silicon, if the photon energy is higher than the silicon band gap value. This generates an electron-hole pair and sometimes heat, depending on the band structure. When a photon is absorbed, its energy is given to an electron in a crystal lattice. Electrons in the valence band may be excited into the conduction band, where they are free to move within the semiconductor. The bond that the electron(s) were a part of form a hole. These holes can move through the lattice creating mobile electron-hole pairs.
- A photon need only have greater energy than that of a band gap to excite an electron from the valence band into the conduction band. Since solar radiation is composed of photons with energies greater than the band gap of silicon, the higher energy photons will be absorbed by the solar cell, with some of the energy (above the band gap) being turned into heat rather than into usable electrical energy.
- A solar cell may be described in terms of a fill factor (FF). FF is a ratio of the maximum power point (Pm) divided by open circuit voltage (Voc) and short circuit current (Jsc):
-
- The fill factor is directly affected by the values of a cell's series and shunt resistance. Increasing the shunt resistance (Rsh) and decreasing the series resistance (Rs) will lead to a higher fill factor, thus resulting in greater efficiency, and pushing the cells output power closer towards its theoretical maximum. The increased efficiency of photovoltaic devices is of utmost importance in the current energy environment.
- To increase efficiency, tandem cells have been employed where a first solar cell is integrated with a second solar cell. Such cells typically employ a microcrystalline Silicon based bottom cell, which includes microcrystalline Silicon for a p-doped layer, an intrinsic layer and an n-doped layer for the cell. These types of cells suffer from slow growth rates during manufacture. The growth rate for high quality microcrystalline cells may be about 2-3 Angstroms/sec for a 1.5 micron thickness, and can take 1-2 hours to grow the microcrystalline Silicon. This results in higher cost. In addition, since a top cell in such device also includes a form of Silicon, current sharing between the top and bottom cells is excessive, e.g., Jsc for the tandem device is often less than Jsc for an individual cell.
- Thin-film materials of the type Cu(In,Ga)(S,Se)2 (CIGS), while efficient, include rare indium metal, which is expected to be of high cost and short supply in future large-scale photovoltaic device production—an issue which is further exacerbated by the growing indium consumption for thin film display production. Other materials such as Cu2S and CdTe have also been proposed as absorbers but while Cu2S suffers from low stability in devices, rare tellurium and toxic cadmium limits CdTe usage.
- A photosensitive device and method includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween. A bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer therebetween. The bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide.
- A photosensitive device includes a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween. A bottom cell has an N-type layer, a P-type layer and a bottom intrinsic layer therebetween. The bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1, wherein z is controlled to adjust a band gap of the bottom cell to be lower than a band gap of the top cell.
- A method for fabrication of a tandem photovoltaic device includes forming a bottom cell having an N-type layer, a P-type layer and a bottom intrinsic layer therebetween, wherein the bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide; and forming a top cell over the bottom cell to form a tandem cell, the top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween.
- These and other features and advantages will become apparent from the following detailed description of illustrative embodiments thereof, which is to be read in connection with the accompanying drawings.
- The disclosure will provide details in the following description of preferred embodiments with reference to the following figures wherein:
-
FIG. 1 is a cross-sectional view of an illustrative tandem cell device structure in accordance with the present principles; -
FIG. 2A is a plot of external quantum efficiency (EQE) versus wavelength for top and bottom cells of a conventional tandem cell; -
FIG. 2B is a plot of external quantum efficiency (EQE) versus wavelength for top and bottom cells of a tandem cell in accordance with the present principles; and -
FIG. 3 is a flow diagram showing a method for fabricating a tandem cell in accordance with the present principles. - In accordance with the present principles, a new tandem solar cell device structure is provided that increases productivity and performance over conventional cells which typically employ microcrystalline silicon bottom cells. Greater efficiency is provided at least in part by less current sharing between top and bottom cells in the tandem structure. Further, the present embodiments provide tandem cells composed of materials which are rapidly grown or applied with high quality. This makes the present embodiments more cost effective in addition to other advantages.
- In one illustrative embodiment, a tandem cell is fabricated having a one cell fabricated using a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1. In a particularly useful embodiment, Cu2ZnSn(S, Se)4 (CZTS or CZTSe) is employed. CZTS has many benefits. It is low cost and environmentally harmless being fabricated using naturally abundant materials. CZTS provides good optical properties and has a band-gap energy from approximately 1 to 1.5 eV depending on the degree of substitution of S with Se and a large absorption coefficient in the order of 104 cm−1. Eliminating the reliance on rare indium metal (also heavily consumed by one of the fastest growing industries—thin film displays) opens the possibility of almost limitless material supply for production capacities well above 100 GWp/year. The efficiency of CZTS, e.g., in the 10% range, can be maximized by making a tandem cell with amorphous silicon having higher band gap and thus allowing more effective light harvesting across the solar spectrum.
- Aspects of the present invention are described below with reference to flowchart illustrations and/or block diagrams of methods and devices according to embodiments of the invention. The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations according to various embodiments of the present invention. It should also be noted that, in some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.
- It is to be understood that the present invention will be described in terms of a given illustrative architecture for tandem cell photovoltaic devices; however, other architectures, structures, substrate materials and process features and steps may be varied within the scope of the present invention.
- The devices described here may be part of a circuit and include a design for an integrated circuit chip, a photovoltaic device, a photosensitive circuit, etc. The design may be created in a graphical computer programming language, and stored in a computer storage medium (such as a disk, tape, physical hard drive, or virtual hard drive such as in a storage access network). The designer may transmit the resulting design by physical means (e.g., by providing a copy of the storage medium storing the design) or electronically (e.g., through the Internet) to entities, directly or indirectly. The stored design may be converted into the appropriate format (e.g., GDSII) for the fabrication of photolithographic masks, which typically include multiple copies of the design in question that are to be formed on a substrate. The photolithographic masks are utilized to define areas of the substrate (and/or the layers thereon) to be etched or otherwise processed.
- The methods as described herein may be used in the fabrication of integrated circuit chips, a photovoltaic device, a photosensitive circuit, etc. The device may be integrated with other chips, discrete circuit elements, and/or other signal processing devices as part of either (a) an intermediate product, such as a printed wiring board, or (b) an end product. The end product can be any product that includes devices, ranging from toys and other low-end applications to advanced computer products having a display, a keyboard or other input device, and a central processor.
- Referring now to the drawings in which like numerals represent the same or similar elements and initially to
FIG. 1 , an illustrative tandemphotovoltaic structure 100 is illustratively depicted in accordance with one embodiment. Thephotovoltaic structure 100 may be employed in solar cells, light sensors, photosensitive devices or other photovoltaic applications. The embodiment depicted inFIG. 1 includes twocells - A
top cell 102 includes a first dopedlayer 106 which may include amorphous silicon (e.g., a-Si:H) or other suitable materials for thin film solar cells. In this embodiment, the first dopedlayer 106 includes an N-type (n+) doping. Alayer 108 may include a transparent electrode (transparent conducting oxide (TCO)). Thefirst layer 106 provides a first doping layer for thetop cell 102. - An
intrinsic layer 110 includes a material compatible withlayer 106 and alayer 112. Theintrinsic layer 110 is undoped. In one illustrative embodiment,layer 110 includes amorphous silicon (a-Si:H) although other materials may also be employed. Theintrinsic layer 110 may have a thickness of between about 100 to 300 nm. -
Layer 112 has an opposite polarity relative to the layer 106 (e.g., iflayer 106 is N-type thenlayer 112 is P-type or vice versa). In this example,layer 112 is a P-type material andlayer 106 is an N-type material. In this embodiment,layer 112 may include a P-type (p+) microcrystalline silicon (μc-Si:H) layer.Layer 112 is preferably thin, e.g., 1 nm to about 10 nm, and more preferably around 5 nm.Layer 112 forms a second doped layer of thetop cell 102. Different combinations of materials may be employed to form the photovoltaic stack forcell 102, for example, a-SiC:H or other higher band-gap materials. Thetop cell 102 is preferably formed to have band gap materials that have a higher band gap than the materials inbottom cell 104. -
Layers top cell 102 andlayers bottom cell 104 to provide thedouble junction device 100. Thetandem cells top cell 102 has a high likelihood of being absorbed in thebottom cell 104. - Between
layers 112 and 114, which may be tunnel junctions, hydrogen plasma may be applied on layer 114 to enhance the crystallinity of the subsequently grownlayer 112 on layer 114 so that conductivity of the tunnel junction can be improved. - In one embodiment, the
bottom cell 104 employs alayer 120 on asubstrate 122. Thelayer 120 may include molybdenum although other high work-function materials may be employed (e.g., Pt, Au, etc.). Thesubstrate 122 may include glass or other inexpensive substrates, such as metal, plastic, etc. Thelayer 120 provides a metal contact while layer 114 is an N-type material (e.g., n-CdS). Layer 120 (e.g., Mo layer) can be thicker than layer 114 to enable sufficient conductivity for adequate series resistance. - The layer 114 may include CdS or other materials that serve as an N-type layer.
Layer 116 includes a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1. The Cu—Zn—Sn-containing chalcogenide, such as a Cu2ZnSn(S,Se)4 (CZTS) based thin film, serves as a P-type material. In one embodiment, the CZTS film has a thickness of between about 0.2 to 4.0 microns and more preferably about 2 microns.Layer 116 may be formed by painting, sputtering, electroplating, spin coating or other simple coating processes. The process of forminglayer 116 is reduced to a few minutes or less from the hours required in forming a microcrystalline silicon layer in conventional devices. - Layer 114 is preferably thin, e.g., 1 nm to about 10 nm, more preferably around 5 nm. The layer 114 provides an N-type layer for the
bottom cell 104. Theintrinsic layer 116 contacts layer 114 andlayer 120. Theintrinsic layer 116 is undoped or slightly p-doped. In one illustrative embodiment,intrinsic layer 116 includes CZTS (or CZTS with some Se substituted for S) which provides a band gap (Eg) from about 1 to 1.5 eV. It is desirable that the band gap of theintrinsic layer 110 of thetop cell 102 be greater than the band gap of thebottom cell 104.Layer 120 forms a bottom electrode of thebottom cell 104. - The deposition sequence can be completely opposite for a superstrate configuration (e.g., where light instead comes from the substrate 122). In this case, a top a-Si:H or a-SiC:H cell is deposited on top of a TCO/glass substrate (122). Then, the bottom cell (with CZTS) is formed by forming a p-type tunnel junction on top of the top intrinsic layer of the top cell. Molybdenum would be deposited for the electrode, the CZTS absorber is formed and then capped with CdS.
- It should be understood that the CZTS process temperature should not exceed ˜250 degrees C. since hydrogen in a-Si:H starts being evaporated out such that there is no more H passivation on broken bonds.
-
Tandem cell device 100 is fabricated to maximize VOC and improve current matching between each junction. Multiple junctions are formed together so that the VOC of each junction is cumulatively added resulting in a high VOC for the multi-junction device due to the tandem cells. The JSC of thetandem cell device 100 is controlled by a single junction device, i.e., the device with the lowest JSC. To increase the performance of thedevice 100, it is desirable that any radiation that passes through thetop cell 102 is absorbed in the bottom cell 104 (or middle cells if available). This is achieved by providing energy gap splitting (Eg splitting). For example, thetop cell 102 has higher band gap materials and receives light first. The light spectra that is not absorbed at thetop cell 102 enters thebottom cell 104. A larger band gap difference between two different junctions is better to prevent the light spectra from being shared between the junctions to maximize photocurrent. Energy gap splitting permits the absorption of radiation with different energies between the cells. Since the band gap of thetop cell 102 is maintained at a higher level, the lower level cell (104) or cells are designed to have a lower band gap. In this way, the lower cells have a higher probability of absorbing transmitted radiation, and the entire tandem cell becomes more efficient since there are fewer photon energy levels shared between the layered cells. This results in increased probability of absorbing light passing through to thebottom cell 104 hence increasing the current in thebottom cell 104, increasing JSC. It is preferable that a greater difference between band gaps exists between the top cell 102 (higher band gap), and the bottom cell 104 (lower band gap) by keeping an absolute high level of band gap energy for both cells to maintain high Voc. If separating Eg by reducing the band gap of the bottom cell is excessive, there will be Voc loss. - It should be understood that while a double junction tandem device is shown and described with respect to
FIG. 1 , additional junctions may be added as needed to provide a triple junction, etc. For example, thetandem device 100 may include at least one middle cell having an N-type layer, a P-type layer and a middle intrinsic layer therebetween which preferably includes a band gap energy between that of the top intrinsic layer and the bottom intrinsic layer. - Referring to
FIG. 2A , a plot of external quantum efficiency (EQE) versus wavelength is shown for a conventional thin film silicon tandem cell. The tandem cell inFIG. 2A includes an amorphous silicon top cell and a microcrystalline silicon bottom cell. Plot 202 shows the top cell response, andplot 204 shows the bottom cell response for the microcrystalline silicon bottom cell over a wavelength range of 350 -1200 nm. - Referring to
FIG. 2B , a plot of external quantum efficiency (EQE) versus wavelength is shown for a tandem cell in accordance with the present principles. The tandem cell inFIG. 2B includes an amorphous silicon top cell and a CZTS bottom cell. Plot 206 shows the top cell response, which is the same response as inFIG. 2A since the structure is the same for the top cell inplots plot 208 shows the bottom cell response for the CZTS bottom cell over a wavelength range of 350 -1200 nm. Note that there significantly less wavelength overlap between thetop cell plot 206 and thebottom cell plot 208 than inFIG. 2A . This translates to a greater amount of radiation absorption with less competition for the same wavelength light between cells. - EQE is a quantity defined for a photosensitive device as the percentage of photons hitting the photoreactive surface that will produce an electron-hole pair (measurement of the device's electrical sensitivity to light at a certain wavelength). Since the energy of a photon is inversely proportional to its wavelength, EQE is measured over a range of different wavelengths to characterize a device's efficiency at each photon energy. The quantum efficiency of a solar cell gives information on the current that a given cell will produce when illuminated by a particular wavelength. If the quantum efficiency is integrated (summed) over the whole solar electromagnetic spectrum (area under the curve), the current that a cell will produce when exposed to the solar spectrum can be determined.
- As can be seen, from
plot 204 inFIG. 2A andplot 208 inFIG. 2B , the area under the EQE curve is significantly larger for the bottom cell with the CZTS inFIG. 2B . Note for example, the plot rises to almost 1.0 at a wavelength of about 600 nm and is significantly higher over the entire spectrum as compared withplot 204 inFIG. 2A . - With solar cells, EQE is the current obtained outside the device per incoming photon. EQE=(electrons/sec)/(photons/sec), and the efficiency=output/input. EQE therefore depends on both the absorption of light and the collection of charge. Once a photon has been absorbed and has generated an electron-hole pair, these charges need to be separated and collected at the junction.
- Table I shows illustrative data for different device types. Table I includes open circuit voltage (Voc), short circuit current (Jsc), fill factor (FF) and Efficiency.
-
TABLE I Cell Parameters: Voc Jsc FF Efficiency Device Type (V) (mA/cm2) (%) (%) Conventional a-Si/μc-Si 1.4 12 73 12.3 Tandem a-Si/CZTS 1.4 15~16 73 15~16 - Single cell devices include efficiencies in the 9% range. Even a stand-alone CZTS device has a measured efficiency of about 9.6%. The conventional a-Si/μ-Si tandem cell provides an efficiency of about 12.3%. The tandem a-Si/CZTS in accordance with the present principles provides an expected efficiency of about 15-16% representing a significant gain in efficiency with lower production costs and lower material costs.
- Referring to
FIG. 3 , a flow diagram for fabrication of a tandem photovoltaic device is illustratively shown in accordance with one embodiment. Inblock 302, a bottom cell is formed. The bottom cell includes an N-type layer, a P-type layer and a bottom intrinsic layer formed therebetween. The bottom cell may be formed on a substrate, such as a glass substrate or the like. The bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1. - The bottom cell preferably includes molybdenum as a back contact layer formed on a glass substrate, although other high work-function metals may be employed (e.g., Pt, Au, etc.). The bottom cell preferably includes a layer of cadmium sulfide as the N-type layer, although other N-type layers can also be employed, including, e.g., ZnS, Zn(O,S) (zinc oxysulfide), In2S3 and ZnO.
- In
block 304, the bottom intrinsic layer can be prepared by any standard vacuum or non-vacuum deposition technique. In useful embodiments, the bottom intrinsic layer can be prepared by evaporation, sputtering, electroplating, casting, spraying (painting) and printing. The bottom intrinsic layer is preferably formed by an ink-based coating or printing process. A liquid, ink-based technique is suitable for large-scale low-cost manufacturing. The coating process is preferably performed in the order of minutes and more preferably in less than one minute. - An example preparation of a Cu2ZnSn(S,Se)4 film by ink (slurry) spin coating includes the following. All operations were performed in a nitrogen-filled glove box. The deposition solution was prepared in two parts in glass vials under magnetic stirring: Part A1 was formed by dissolving Cu2S, 0.573 g and sulfur, 0.232 g in 3 ml of hydrazine and part B1 was formed by mixing SnSe, 0.790 g, Se, 1.736g and Zn, 0.32 g with 7 ml of hydrazine. After 3 days under magnetic stirring, solution A1 had an orange transparent aspect, while B1 was dark green and opaque. Solutions A1 and B1 were mixed (C1) before deposition.
- Films were deposited on soda lime glass substrates coated with 700 nm molybdenum by spin coating at 800 rpm and heated at 540° C. for 2 minutes. The coating and heating cycle were repeated 5 times before a final anneal was carried out for 10 minutes.
- In
block 305, for Cu2-xZn1+ySn(S1-zSez)4+q where 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1, z is controlled during formation to adjust a band gap of the bottom cell. The tandem cell in accordance with the present principles has a band gap of the bottom cell intrinsic layer controlled to be lower than a band gap of the top cell. The optical band gap may be tuned from approximately 1 to 1.5 eV by controlled substitution of the sulfur with selenium. - In
block 306, a top cell is formed over the bottom cell to form a tandem cell. The top cell has an N-type layer, a P-type layer and a top intrinsic layer therebetween. The top cell may include amorphous silicon as the top intrinsic layer, doped amorphous silicon as the N-type layer and doped microcrystalline silicon as the P-type layer. Other materials may be employed for the top cell as well, e.g., SiC, etc. - In
block 308, processing is continued to complete the device. It should be understood that the N-type and P-type layer may be switched relative to each intrinsic layer. Further, in some embodiments, the top cell may be fanned first followed by the bottom cell. In other embodiments, additional cells (e.g., middle cells) may be fabricated in the tandem device. - Having described preferred embodiments for a tandem cell device and method for forming (which are intended to be illustrative and not limiting), it is noted that modifications and variations can be made by persons skilled in the art in light of the above teachings. It is therefore to be understood that changes may be made in the particular embodiments disclosed which are within the scope of the invention as outlined by the appended claims. Having thus described aspects of the invention, with the details and particularity required by the patent laws, what is claimed and desired protected by Letters Patent is set forth in the appended claims.
Claims (25)
1. A photosensitive device, comprising:
a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween; and
a bottom cell having an N-type layer, a P-type layer and a bottom intrinsic layer therebetween, the bottom intrinsic layer including a Cu—Zn—Sn containing chalcogenide.
2. The device as recited in claim 1 , wherein the Cu—Zn—Sn containing chalcogenide is a compound with a kesterite structure of the formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1.
3. The device as recited in claim 1 , wherein the bottom intrinsic layer includes a deposited ink material.
4. The device as recited in claim 1 , wherein the bottom cell includes a high-work-function metal as the P-type layer.
5. The device as recited in claim 4 , wherein the high-work-function metal includes molybdenum.
6. The device as recited in claim 5 , wherein the molybdenum is formed on a glass substrate.
7. The device as recited in claim 1 , wherein the bottom cell includes a layer of cadmium sulfide as the N-type layer.
8. The device as recited in claim 1 , wherein the top cell includes amorphous silicon as the top intrinsic layer.
9. The device as recited in claim 1 , wherein the top cell includes doped amorphous silicon as the N-type layer and includes doped microcrystalline silicon as the P-type layer.
10. A photosensitive device, comprising:
a top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween; and
a bottom cell having an N-type layer, a P-type layer and a bottom intrinsic layer therebetween, the bottom intrinsic layer including a Cu—Zn—Sn containing chalcogenide compound with a kesterite structure of the formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; =1≦q≦1, wherein z is controlled to adjust a band gap of the bottom cell to be lower than a band gap of the top cell.
11. The device as recited in claim 10 , wherein the top cell includes amorphous silicon as the top intrinsic layer.
12. The device as recited in claim 10 , wherein the top cell includes doped amorphous silicon as the N-type layer and includes doped microcrystalline silicon as the P-type layer.
13. The device as recited in claim 10 , wherein the bottom intrinsic layer includes a deposited ink material.
14. The device as recited in claim 10 , wherein the bottom cell includes a layer of cadmium sulfide as the N-type layer.
15. A method for fabrication of a tandem photovoltaic device, comprising:
forming a bottom cell having an N-type layer, a P-type layer and a bottom intrinsic layer therebetween, wherein the bottom intrinsic layer includes a Cu—Zn—Sn containing chalcogenide; and
forming a top cell over the bottom cell to form a tandem cell, the top cell having an N-type layer, a P-type layer and a top intrinsic layer therebetween.
16. The method as recited in claim 15 , wherein the Cu—Zn—Sn containing chalcogenide includes a kesterite structure of a formula: Cu2-xZn1+ySn(S1-zSez)4+q wherein 0≦x≦1; 0≦y≦1; 0≦z≦1; −1≦q≦1.
17. The method as recited in claim 16 , further comprising adjusting z to control a band gap of the bottom intrinsic layer such that the band gap of the bottom cell is lower than a band gap of the top cell.
18. The method as recited in claim 15 , wherein the bottom cell includes molybdenum as the P-type layer formed on a glass substrate.
19. The method as recited in claim 15 , wherein the bottom cell includes a layer of cadmium sulfide as the N-type layer.
20. The method as recited in claim 15 , wherein the top cell includes amorphous silicon as the top intrinsic layer.
21. The method as recited in claim 15 , wherein the top cell includes doped amorphous silicon as the N-type layer and includes doped microcrystalline silicon as the P-type layer.
22. The method as recited in claim 15 , wherein the bottom intrinsic layer is formed by a coating process.
23. The method as recited in claim 22 , wherein the coating process is performed in less than one minute.
24. The method as recited in claim 22 , wherein the coating process includes an ink deposition.
25. The method as recited in claim 22 , wherein the coating process includes one of sputtering, electroplating or spin-coating.
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/037,798 US20120222730A1 (en) | 2011-03-01 | 2011-03-01 | Tandem solar cell with improved absorption material |
DE112012001058.2T DE112012001058B4 (en) | 2011-03-01 | 2012-01-26 | METHOD FOR PRODUCING A TANDEM PHOTOVOLTAIC UNIT |
CN2012800109200A CN103403876A (en) | 2011-03-01 | 2012-01-26 | Tandem solar cell with improved absorption material |
PCT/US2012/022708 WO2012118577A1 (en) | 2011-03-01 | 2012-01-26 | Tandem solar cell with improved absorption material |
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Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103325879A (en) * | 2013-07-03 | 2013-09-25 | 黑龙江汉能薄膜太阳能有限公司 | High efficient three-lamination-layer heterojunction film solar cell and preparation method thereof |
US20160035927A1 (en) * | 2014-08-01 | 2016-02-04 | International Business Machines Corporation | Tandem Kesterite-Perovskite Photovoltaic Device |
US20160087233A1 (en) * | 2014-09-19 | 2016-03-24 | International Business Machines Corporation | Monolithic Tandem Chalcopyrite-Perovskite Photovoltaic Device |
US9443997B2 (en) | 2013-06-28 | 2016-09-13 | International Business Machines Corporation | Hybrid CZTSSe photovoltaic device |
US10121920B2 (en) | 2015-06-30 | 2018-11-06 | International Business Machines Corporation | Aluminum-doped zinc oxysulfide emitters for enhancing efficiency of chalcogenide solar cell |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105742390B (en) * | 2014-12-12 | 2018-03-13 | 北京创昱科技有限公司 | A kind of overlapping thin film solar battery and preparation method thereof |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4878097A (en) * | 1984-05-15 | 1989-10-31 | Eastman Kodak Company | Semiconductor photoelectric conversion device and method for making same |
US6121541A (en) * | 1997-07-28 | 2000-09-19 | Bp Solarex | Monolithic multi-junction solar cells with amorphous silicon and CIS and their alloys |
US20090142878A1 (en) * | 2007-11-02 | 2009-06-04 | Applied Materials, Inc. | Plasma treatment between deposition processes |
US20090255578A1 (en) * | 2008-01-15 | 2009-10-15 | First Solar, Inc. | Plasma-treated photovoltaic devices |
US7611573B2 (en) * | 2004-04-02 | 2009-11-03 | Alliance For Sustainable Energy, Llc | ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells |
US20110279141A1 (en) * | 2010-05-12 | 2011-11-17 | Yun Wang | High Throughput Current-Voltage Combinatorial Characterization Tool and Method for Combinatorial Solar Test Substrates |
US20120055554A1 (en) * | 2009-05-21 | 2012-03-08 | E.I. Du Pont De Nemours And Company | Copper zinc tin chalcogenide nanoparticles |
US20120067408A1 (en) * | 2010-09-16 | 2012-03-22 | Solexant Corp. | Sintered CZTS Nanoparticle Solar Cells |
US20120192913A1 (en) * | 2011-01-31 | 2012-08-02 | International Business Machines Corporation | Mixed temperature deposition of thin film silicon tandem cells |
Family Cites Families (16)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4536607A (en) | 1984-03-01 | 1985-08-20 | Wiesmann Harold J | Photovoltaic tandem cell |
US5298086A (en) * | 1992-05-15 | 1994-03-29 | United Solar Systems Corporation | Method for the manufacture of improved efficiency tandem photovoltaic device and device manufactured thereby |
DE19581590T1 (en) * | 1994-03-25 | 1997-04-17 | Amoco Enron Solar | Increasing the stability behavior of devices based on amorphous silicon, which are produced by plasma deposition with high-grade hydrogen dilution at a lower temperature |
US6087580A (en) * | 1996-12-12 | 2000-07-11 | Energy Conversion Devices, Inc. | Semiconductor having large volume fraction of intermediate range order material |
JP2006516819A (en) * | 2003-01-30 | 2006-07-06 | ユニバーシティ・オブ・ケープ・タウン | Thin film semiconductor device and manufacturing method of thin film semiconductor device |
FR2886460B1 (en) * | 2005-05-25 | 2007-08-24 | Electricite De France | SULFURIZATION AND SELENISATION OF CIGS LAYERS ELECTRODEPOSE BY THERMAL RECEIVER |
JP4688589B2 (en) * | 2005-06-30 | 2011-05-25 | 三洋電機株式会社 | Stacked photovoltaic device |
WO2007134843A2 (en) * | 2006-05-24 | 2007-11-29 | Atotech Deutschland Gmbh | Metal plating composition and method for the deposition of copper-zinc-tin suitable for manufacturing thin film solar cell |
US20080135083A1 (en) | 2006-12-08 | 2008-06-12 | Higher Way Electronic Co., Ltd. | Cascade solar cell with amorphous silicon-based solar cell |
JP5007907B2 (en) * | 2008-05-09 | 2012-08-22 | 株式会社豊田中央研究所 | Etching solution and method for manufacturing semiconductor device |
US20100078059A1 (en) * | 2008-09-30 | 2010-04-01 | Stion Corporation | Method and structure for thin film tandem photovoltaic cell |
US20100147361A1 (en) | 2008-12-15 | 2010-06-17 | Chen Yung T | Tandem junction photovoltaic device comprising copper indium gallium di-selenide bottom cell |
DE102009009550A1 (en) * | 2009-02-19 | 2010-09-02 | Carl Von Ossietzky Universität Oldenburg | A process for wet chemically synthesizing dicopper-zinc-tin-tetrasulfide and / or tetraselenide (CZTS), a process for producing a semiconductor layer from CZTS and a colloidal suspension |
US9093190B2 (en) * | 2009-05-26 | 2015-07-28 | Purdue Research Foundation | Synthesis of multinary chalcogenide nanoparticles comprising Cu, Zn, Sn, S, and Se |
CN101723336B (en) * | 2009-12-04 | 2011-08-10 | 中国科学院上海技术物理研究所 | Preparation method of Cu2ZnSnSxSe4-x nanocrystal |
CN101840942A (en) * | 2010-05-19 | 2010-09-22 | 深圳丹邦投资集团有限公司 | Thin-film solar cell and manufacturing method thereof |
-
2011
- 2011-03-01 US US13/037,798 patent/US20120222730A1/en not_active Abandoned
-
2012
- 2012-01-26 CN CN2012800109200A patent/CN103403876A/en active Pending
- 2012-01-26 DE DE112012001058.2T patent/DE112012001058B4/en active Active
- 2012-01-26 WO PCT/US2012/022708 patent/WO2012118577A1/en active Application Filing
-
2015
- 2015-06-01 US US14/727,071 patent/US9806211B2/en active Active
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4878097A (en) * | 1984-05-15 | 1989-10-31 | Eastman Kodak Company | Semiconductor photoelectric conversion device and method for making same |
US6121541A (en) * | 1997-07-28 | 2000-09-19 | Bp Solarex | Monolithic multi-junction solar cells with amorphous silicon and CIS and their alloys |
US7611573B2 (en) * | 2004-04-02 | 2009-11-03 | Alliance For Sustainable Energy, Llc | ZnS/Zn(O,OH)S-based buffer layer deposition for solar cells |
US20090142878A1 (en) * | 2007-11-02 | 2009-06-04 | Applied Materials, Inc. | Plasma treatment between deposition processes |
US20090255578A1 (en) * | 2008-01-15 | 2009-10-15 | First Solar, Inc. | Plasma-treated photovoltaic devices |
US20120055554A1 (en) * | 2009-05-21 | 2012-03-08 | E.I. Du Pont De Nemours And Company | Copper zinc tin chalcogenide nanoparticles |
US20110279141A1 (en) * | 2010-05-12 | 2011-11-17 | Yun Wang | High Throughput Current-Voltage Combinatorial Characterization Tool and Method for Combinatorial Solar Test Substrates |
US20120067408A1 (en) * | 2010-09-16 | 2012-03-22 | Solexant Corp. | Sintered CZTS Nanoparticle Solar Cells |
US20120192913A1 (en) * | 2011-01-31 | 2012-08-02 | International Business Machines Corporation | Mixed temperature deposition of thin film silicon tandem cells |
Non-Patent Citations (2)
Title |
---|
Chaure, N.B. et al., "Electrodeposition of p+, p, i, n and n+-type copper indium gallium diselenide for development of multilayer thin film solar cells", 2005, Thin Solid Films 472, pp. 212-216. * |
Chen, Shiyou et al., "Crystal and electronic band structure of Cu2ZnSnX4 (X=S and Se) photovoltaic absorbers: First principles insights", 2009, Applied Physics Letters 94, 041903, pp. 1-3. * |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9443997B2 (en) | 2013-06-28 | 2016-09-13 | International Business Machines Corporation | Hybrid CZTSSe photovoltaic device |
US10505066B2 (en) | 2013-06-28 | 2019-12-10 | International Business Machines Corporation | Hybrid CZTSSe photovoltaic device |
US11355661B2 (en) | 2013-06-28 | 2022-06-07 | International Business Machines Corporation | Hybrid CZTSSe photovoltaic device |
CN103325879A (en) * | 2013-07-03 | 2013-09-25 | 黑龙江汉能薄膜太阳能有限公司 | High efficient three-lamination-layer heterojunction film solar cell and preparation method thereof |
US20160035927A1 (en) * | 2014-08-01 | 2016-02-04 | International Business Machines Corporation | Tandem Kesterite-Perovskite Photovoltaic Device |
US20160087233A1 (en) * | 2014-09-19 | 2016-03-24 | International Business Machines Corporation | Monolithic Tandem Chalcopyrite-Perovskite Photovoltaic Device |
US9627576B2 (en) * | 2014-09-19 | 2017-04-18 | International Business Machines Corporation | Monolithic tandem chalcopyrite-perovskite photovoltaic device |
US10121920B2 (en) | 2015-06-30 | 2018-11-06 | International Business Machines Corporation | Aluminum-doped zinc oxysulfide emitters for enhancing efficiency of chalcogenide solar cell |
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US9806211B2 (en) | 2017-10-31 |
DE112012001058B4 (en) | 2019-08-29 |
US20150263199A1 (en) | 2015-09-17 |
DE112012001058T5 (en) | 2013-12-05 |
WO2012118577A1 (en) | 2012-09-07 |
CN103403876A (en) | 2013-11-20 |
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