Photo-EMF Sensitivity of Porous Silicon Thin Layer–Crystalline Silicon Heterojunction to Ammonia Adsorption

Sensors

Yuriy Vashpanov¹  Jae Il Jung² 

[1] Electrical and Computer Engineering Division, Hanyang Institute of Technology, Hanyang University, 17 Haengdang-dong, Sung-dong-gu, 133-791 Seoul, Korea; E-Mail

关键词: gas sensors;    porous silicon;    heterojunction;    photo-EMF;   

DOI  :  10.3390/s110201321

来源: mdpi

【 摘 要 】

A new method of using photo-electromotive force in detecting gas and controlling sensitivity is proposed. Photo-electromotive force on the heterojunction between porous silicon thin layer and crystalline silicon wafer depends on the concentration of ammonia in the measurement chamber. A porous silicon thin layer was formed by electrochemical etching on p-type silicon wafer. A gas and light transparent electrical contact was manufactured to this porous layer. Photo-EMF sensitivity corresponding to ammonia concentration in the range from 10 ppm to 1,000 ppm can be maximized by controlling the intensity of illumination light.

【 授权许可】

CC BY   
© 2011 by the authors; licensee MDPI, Basel, Switzerland.