CN101382604B

CN101382604B - Single-component strontium barium titanate optical micro-cavity and building method

Info

Publication number: CN101382604B
Application number: CN2008102015379A
Authority: CN
Inventors: 胡古今; 商景林; 戴宁; 张婷
Original assignee: Shanghai Institute of Technical Physics of CAS
Current assignee: Shanghai Institute of Technical Physics of CAS
Priority date: 2008-10-22
Filing date: 2008-10-22
Publication date: 2010-06-02
Anticipated expiration: 2028-10-22
Also published as: CN101382604A

Abstract

The invention discloses a mono-strontium titanate barium optical microcavity and a construction method thereof; the method uses precursor solution containing kollidon to regulate and control the microstructure of the strontium titanate barium film by repeated whirl coating filming-heating processing technology and different heating processing condition so as to construct the optical microcavity formed by a strontium titanate barium Bragg reflection film and a uniform phase strontium titanate barium spacer layer. The invention is most characterized in that the reflector and the spacer layer of the optical microcavity are both constructed by the same former chemical solution, and has the advantages of simple used device, convenient operation, low cost and high universality.

Description

Single-component strontium barium titanate optical micro-cavity and construction method

Technical field

The present invention relates to a kind of Fabry-Perot optical microcavity technology of forming by ferroelectric multilayer film, specifically be meant a kind of optical microcavity of forming by barium strontium titanate (BST) Bragg reflection rete and homogeneous phase barium strontium titanate wall and preparation method thereof.

Background technology

Catoptron and optical microcavity are can not break scarce important devices in the light quantum control system.Optical microcavity has brought new opportunity for the research and development of the sub-device of novel photoelectric because of having the quantum electrodynamics effect, as utilize the frequency-selecting of microcavity and, successfully prepared devices such as vertical cavity surface emitting laser, resonance luminescence diode, detector and photoswitch the amplification of electromagnetic field.The common used material that makes up these devices is semiconductor, inorganic oxide or organism mostly.Because these materials itself have very weak even do not have effects such as electric light, acousto-optic, can only under the frequency of operation of setting, move based on the optical microcavity of these material, can't realize the dynamic tuning of chamber mould frequency.And FE compound has big electrooptical coefficient, and the frequency of operation of the optical microcavity of making based on ferroelectric material just might be regulated and control by extra electric field.We are (the number of applying for a patent: 200710038665.1), disclose the preparation method of BST optical microcavity in the patent document 1 of " BST Fabry-Perot micro-cavity and preparation method " by name once.But need to adopt two kinds of different solution to prepare BST Bragg reflection rete and wall respectively in the technological process of this patent introduction, this has increased the cost and the complicacy of the preparation of BST optical microcavity undoubtedly.Recently, we have realized a kind of new technology of the BST of preparation optical microcavity---when catoptron for preparing microcavity and wall,, just can utilize with a kind of precursor solution to prepare high-quality BST optical microcavity as long as adopt different heat-treat conditions.This method advances and expands the application of BST optical microcavity in fields such as integrated opto-electronic device, optical communication, photometry calculations and all will play a positive role reducing the preparation cost of BST optical microcavity

Summary of the invention

Purpose of the present invention: a kind of simple and easy method that utilizes the good and tunable BST optical microcavity of frequency of operation of single precursor solution processability is provided.

Optical microcavity structure of the present invention comprises: the strontium titanate monocrystal substrate, on substrate by chemical solution method be arranged in order the growth following structure rete:

DBR\Spacer\DBR；

DBR in the above-mentioned rete is the BST multilayer dielectric reflective coating in 5-20 cycle, and the thickness of every layer of dielectric reflection film is 60-200nm; Spacer is the BST wall of homogeneous phase, and its thicknesses of layers is 30-100nm.

BST optical microcavity among the present invention adopts the chemical solution method growth, and its process is as follows:

1. be used to prepare the preparation of the precursor solution of BST optical microcavity:

Solvent is a glacial acetic acid, and stabilizing agent is a diacetone, and adjuvant is a polyvinylpyrrolidone, and their mol ratio is 25～35: 0.5～1.5: 0.5～1.5.

Solute is strontium acetate, barium acetate, normal butyl alcohol titanium, and their mol ratio is (1-x): x: 1, and 0＜x＜1 wherein.Earlier strontium acetate, barium acetate are dissolved in the glacial acetic acid of heat, treat successively diacetone, normal butyl alcohol titanium, polyvinylpyrrolidone to be added lasting stirring the in the above-mentioned solution behind the solution cool to room temperature, be adjusted into 0.3M/L by the concentration of diluting or distill, and filter the precursor solution that obtains clear solution.

2.BST the preparation of optical microcavity rete:

The microcavity rete adopts conventional spin coating coating process, prepares on the strontium titanates substrate successively by above-mentioned film layer structure.

Basic conception of the present invention is: the nearly periodic BST reflectance coating of method growth that adopts statement in the patent document 1 (application number 200710038665.1).Outstanding novelty shows in the making of BST wall: by 200 ℃-400 ℃ sub zero treatment, make the ground floor BST that at first is deposited on the reflective coating 2 form amorphous phase; When continuing deposition BST, because the bst thin film of last growth is in amorphous state, the bst thin film surface does not have electric polarity, is randomly dispersed in the gelling film by the polyvinylpyrrolidone nanometer aggregation that produces that is separated, and can not produce the space and distribute according to qualifications; Handle through 700 ℃-750 ℃ high temperature crystallization, the bst film of twice deposition all changes into the perovskite ferroelectrics before and after making again, and the film that deposits for the second time shows as the structure of homogeneous phase, and this layer is as the wall of whole microcavity.

A distinguishing feature of the present invention is: the catoptron of optical microcavity and wall are all used with a kind of chemical solution and are constructed; Its advantage is: device therefor is simple, and is easy to operate, and cost is low, and universality is strong.

Description of drawings

Fig. 1 has provided the structural representation of BST optical microcavity, and 1 and 3 are respectively substrate and wall, and 2 and 4 is that two BST multilayer dielectric reflective coatings are piled up and down.

Fig. 2 is the reflectance spectrum of BST optical microcavity.Curve 1 corresponding space layer is the microcavity of 48nm; Curve 2 corresponding space layers are the microcavity of 62nm.

Embodiment

Below in conjunction with drawings and Examples, the specific embodiment of the present invention is described in further detail:

Embodiment 1

The barium strontium is than being the preparation of 90/10 solution:

Solvent is a glacial acetic acid, and stabilizing agent is a diacetone, and adjuvant is a polyvinylpyrrolidone.

Solute is barium acetate, strontium acetate, normal butyl alcohol titanium, and their mol ratio is 0.9: 0.1: 1.With the 2.7864g barium acetate, 0.2603g strontium acetate, 0.65g polyvinylpyrrolidone is dissolved in the glacial acetic acid of 30ml heating, the diacetone that adds about 2ml then, stir and make its cooling, add 4.2ml normal butyl alcohol titanium at last and also continued to stir 2-3 hour, add a small amount of glacial acetic acid dilution, and filtration obtains the BST precursor solution as clear as crystal, that volumetric molar concentration is about 0.3M/L.

Embodiment 2

Contain the preparation of the BST Bragg reflection rete 2 in 10 cycles:

Utilize the spin coating coating process, the rotating speed that changes with per minute 3000, with prepare among the embodiment 1, the barium strontium drips to than the precursor solution that is 90/10 on the strontium titanate monocrystal substrate 1 that is rotating, the spin coating time is 30 seconds; Then the good slice, thin piece of spin coating is put into quick anneal oven, thermal treatment 4 minutes under the temperature of 200 ℃, 350 ℃ and 750 ℃ respectively 4 minutes and 8 minutes, repeats above-mentioned growth step 10 times, obtain having the BST Bragg reflection rete 2 in 10 cycles, the thickness of rete 2 is about 900nm.

Embodiment 3

The making of BST optical microcavity wall:

The precursor solution for preparing among the embodiment 1 is dripped on the above-mentioned BST reflective coating 2 for preparing, and is the rotating speed spin coating changeed of per minute 3,000 30 seconds with whirl coating speed; Then the good slice, thin piece of spin coating is put into quick anneal oven, thermal treatment 4 minutes under the temperature of 200 ℃ and 350 ℃ respectively, repeat above-mentioned steps 1 time after, then with sample thermal treatment 30 minutes under 750 ℃ temperature, obtain the wall 3 of homogeneous phase, its thickness is about 62nm.

Embodiment 4

Contain the preparation of the BST Bragg reflection rete 4 in 10 cycles:

The precursor solution for preparing among the embodiment 1 being dripped on the above-mentioned wall for preparing, is the rotating speed spin coating changeed of per minute 3,000 30 seconds with whirl coating speed again; Then the good slice, thin piece of spin coating is put into quick anneal oven, thermal treatment 4 minutes under the temperature of 200 ℃, 350 ℃ and 750 ℃ respectively 4 minutes and 8 minutes, repeats above-mentioned growth step 10 times, obtain having the BST Bragg reflection rete 4 in 10 cycles, the thickness of reflective coating 4 is similarly 900nm.Obtaining structure at last is: 3/10 cycle BST of 1/10 cycle BST of strontium titanates substrate Bragg reflection rete 2/ wall Bragg reflection rete 4.

For the chamber mould frequency that optical microcavity is described can obtain regulation and control by changing technological parameter, we change the rotating speed that is coated with optical microcavity reflective coating and wall in the foregoing description into per minute 3500 changes, and the Cycle Length of space layer and multilayer film is diminished.Fig. 2 has provided the reflected spectrum data of these two kinds of optical microcavities, and measurement result shows that the resonance frequency of two microcavitys can regulate and control by the adjusting process parameter really.

Claims

1. single-component strontium barium titanate optical micro-cavity, it is characterized in that: this optical microcavity structure comprises: the strontium titanate monocrystal substrate, on substrate by grow the successively rete of following structure of chemical solution method:

DBR\Spacer\DBR；

DBR in the above-mentioned rete is the barium strontium titanate multilayer dielectric reflective coating in 5-20 cycle, and the thickness of every layer of dielectric reflection film is 60-200nm; Spacer is a barium strontium titanate wall identical with the DBR component, homogeneous phase, and its thicknesses of layers is 30-100nm.

2. the preparation method of a single-component strontium barium titanate optical micro-cavity, it is characterized in that: it may further comprise the steps:

(1) preparation of precursor solution:

Solvent is a glacial acetic acid, and stabilizing agent is a diacetone, and adjuvant is a polyvinylpyrrolidone, and their mol ratio is 25～35: 0.5～1.5: 0.5～1.5;

Solute is strontium acetate, barium acetate, normal butyl alcohol titanium, and their mol ratio is (1-x): x: 1, and 0＜x＜1 wherein;

Earlier strontium acetate, barium acetate are dissolved in the glacial acetic acid of heat, treat successively diacetone, normal butyl alcohol titanium, polyvinylpyrrolidone to be added lasting stirring the in the above-mentioned solution behind the solution cool to room temperature, be adjusted into 0.3M/L by the concentration of diluting or evaporate, and filter the precursor solution that obtains clear solution;

(2) preparation of optical microcavity structure:

Microcavity adopts conventional spin coating coating process, grows on the strontium titanates substrate successively by film layer structure:

A) preparation of strontium barium titanate optical micro-cavity Prague multilayer dielectric reflective coating layer:

Utilizing the spin coating coating process, is the rotating speed that per minute 3000-3500 changes with whirl coating speed, and the precursor solution that step 1 is prepared drips on the strontium titanate monocrystal substrate that is rotating, and the spin coating time is 30-60 second; Then the good slice, thin piece of spin coating is put into quick anneal oven, under 180 ℃-240 ℃, 350 ℃-400 ℃ and 700 ℃-750 ℃ temperature thermal treatment 3-8 minute respectively, 3-8 minute and 5-10 minute, repeat above-mentioned growth step 5 to 20 times, obtain the barium strontium titanate multilayer dielectric reflective coating;

B) preparation of strontium barium titanate optical micro-cavity wall:

The same step a) of spin coating coating process, whirl coating speed is changeed for per minute 3000-3500, and the spin coating time is 30-60 second; Then the good slice, thin piece of spin coating is put into quick anneal oven, under 180 ℃-240 ℃, 350 ℃-400 ℃ temperature thermal treatment 3-8 minute respectively, after repeating above-mentioned plated film and heat treatment step 1 time, last under 700 ℃-750 ℃ temperature thermal treatment 15-30 minute, obtain the strontium barium titanate optical micro-cavity wall.