(12) Umted States Patent (10) Patent No.: US 7,997,142 B2 Chiou et al. (45) Date of Patent: Aug. 16, 2011 (54) LOW PRESSURE SENSOR DEVICE WITH 5,178,016 A 1/1993 Dauenhauef HIGH ACCURACY AND HIGH SENSITIVITY 2 lsifilzsk 6-1 4 (75) Inventors: Jen-Huang Albert Chiou, Libertyville, 6351996 Bl * 3/2002 Nasiri et aI' """"""""" " 73/706 IL (US); Shiuh-Hui Steven Chen, Lake OTHER PUBLICATIONS Zurich, IL (U S) _ _ M. Shrmazoe, Y. Matsuoka, A. Yusakawa, M. Tanabe, “A specral (73) Assignee: Continental Automotive Systems, Inc., Silicon Diaphragm Pressure Sensor with High Output and High Deer park IL (US) Accuracy”, Sensors & Actuators, 2 (1982) 275-282. ’ J . A. Chiou, “Simulations for Thermal Warpage and Pressure ( * ) Notice: Subject to any disclaimer, the term of this IignIi;ea1iity_°f M°1n°2Ighi° C3I\2/I7()3S3I3)re2S3E)1;e Sensors’: IEEE Trans‘ - - v. ac ag1ng,vo . ,pp. - , . Ijlatselg 11S5ZX];eILde(i1O7rdadJuSted under 35 J . A. Chiou, S. Chen, “Thermal Hysteresis andVoltage Shift Analysis ' ' ' ( ) y ayS' for Differential Pressure Sensors”, Sensors and Actuators A: Physical, vol. 135, pp. 107-112, 2007. (21) Appl‘ No‘: 12/534'-'009 J . A. Chiou, S. Chen, “Pressure Nonlinearity of Micromachined _ Piezoresistive Pressure Sensors with Thin Diaphragms under High (22) Flledi JUL 319 2009 Residual Stresses”, Sensors and Actuators A: Physical, vol. 147, pp. 332-339., 2008. (65) Pl‘i0l‘ PllbliC3ti0Il D3133 ELMOS-SMI Pressure Sensor Device, ELMOS Semiconductor AG Us 2011/0023618 A1 Feb 3 2011 (MEMS Sensors) website, date unknown. * cited by examiner (51) Int. Cl. G011’ 7/08 (200601) Primary Examiner * Andre Allen (52) U.S. Cl. ....................................................... .. 73/715 (58) Field of Classification Search ...................... .. None See application file for complete search history. (57) ABSTRACT _ Pressure non-linearity in a low pressure sensor device formed (56) References Clted from a silicon diaphragm with an embedded piezoresistive
