(Invited) Development of CMOS-MEMS Cointegrated Pressure Sensor Using Minimal Fab Process. (24th April 2020)

• Record Type: Journal Article
• Authors: Liu, Yongxun; Akita, Ippei; Matsukawa, Takashi; Tanaka, Hiroyuki; Koga, Kazuhiro; Nemoto, Kazumasa; Khumpuang, Sommawan; Nagao, Masayoshi; Morita, Yukinori; Hara, Shiro
• Is Part Of: ECS transactions. Volume 97:Number 1(2020)
• Page Start: 35
• Page End: 46
• Publication Date: 2020-04-24
• Subjects: Electrochemistry -- Periodicals; Electrochemistry; Periodicals; Electronic journals; Electronic journal; 541.37
• DOI: 10.1149/09701.0035ecst
• Languages: English
• ISSNs: 1938-5862

Abstract

Abstract : PVD-TiN metal gate PMOSFETs and CMOS ring oscillators have successfully been fabricated on circular diaphragms using the developed Minimal Fab CMOS-MEMS cointegrated gate-last process, and their electrical characteristics have systematically been investigated by changing applied pressures to the diaphragms. It was found that the drain current variation (dId ) in the <110> channel PMOSFETs is larger than that in the <100> channel ones. The origin of dId is the mechanical stress-induced mobility change. It was also confirmed that the oscillation frequency of the fabricated CMOS ring oscillator on a circular diaphragm changes from 372 to 405 kHz at different pressures of -30 and +30 kPa. This result implies that the fabricated CMOS-MEMS cointegrated sensor chip is operated as a pressure sensor. The developed CMOS-MEMS cointegrated pressure sensor is suitable for the application to the battery drive IoT sensor systems because the all CMOS integration of the sensor has a low-power consumption.