On an Ammonia Gas Sensor Based on a Pt/AlGaN Heterostructure Field-Effect Transistor

Author

Chen, Tai-You ; Chen, Huey-Ing ; Hsu, Chi-Shiang ; Huang, Chien-Chang ; Chang, Chung-Fu ; Chou, Po-Cheng ; Liu, Wen-Chau

Author_Institution

Dept. of Electr. Eng., Nat. Cheng Kung Univ., Tainan, Taiwan

Volume

33

Issue

4

fYear

2012

fDate

4/1/2012 12:00:00 AM

Firstpage

612

Lastpage

614

Abstract

A new and interesting Pt/AlGaN heterostructure field-effect transistor (HFET)-based ammonia gas sensor is fabricated and investigated. The related ammonia-sensing mechanisms, including direct dissociation of ammonia gas and triple-point model, are presented. Experimentally, the maximum transconductance variation Δg_m and threshold voltage variation ΔV_th are 16.63 mS/mm and 318.1 mV, respectively, upon exposing to a 10 000-ppm NH₃/air gas. In addition, the maximum sensing response and rectification ratio of 113.4 and 2.1 × 10³, respectively, are obtained when 10 000- and 35-ppm NH₃/air gases are introduced. Therefore, the studied Pt/AlGaN HFET shows the promise for ammonia-gas-sensing applications.

Keywords

III-V semiconductors; aluminium compounds; field effect transistors; gallium compounds; gas sensors; organic compounds; platinum; wide band gap semiconductors; HFET-based ammonia gas sensor; Pt-AlGaN; ammonia gas model; heterostructure field-effect transistor; triple-point model; voltage 318.1 mV; Aluminum gallium nitride; Gallium nitride; Gases; HEMTs; Logic gates; MODFETs; Sensors; AlGaN; ammonia; heterostructure field-effect transistor (HFET); sensor;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2012.2184832

Filename

6158572