C. Chang
National Cheng Kung University
IEEE Electron Device Letters | 2012
Tai You Chen; Huey-Ing Chen; Chi Shiang Hsu; Chien Chang Huang; C. Chang; Po Cheng Chou; Wen-Chau Liu
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 Δgm and threshold voltage variation ΔVth 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.
IEEE Sensors Journal | 2013
Chi Shiang Hsu; Huey-Ing Chen; Po Cheng Chou; Jian Kai Liou; Chun Chia Chen; C. Chang; Wen-Chau Liu
The hydrogen-sensing characteristics of a Pd/AlGaN/GaN heterostructure field-effect transistor (HFET) under a nitrogen ambience are studied in this paper. Good and stable hydrogen-sensing behaviors are obtained over the operating temperature from 30<formula formulatype=inline><tex Notation=TeX>
IEEE Transactions on Electron Devices | 2011
Tai You Chen; Huey-Ing Chen; Yi Jung Liu; Chien Chang Huang; Chi Shiang Hsu; C. Chang; Wen-Chau Liu
^{circ}{rm C}
ASME 2008 2nd Multifunctional Nanocomposites and Nanomaterials International Conference | 2008
Sheng-Chung Yang; T. I. Yin; C. Chang
</tex> </formula> to 250<formula formulatype=inline><tex Notation=TeX>
19th Int. Conf. Design Theory and Methodology and 1st Int. Conf. Micro and Nano Systems, presented at - 2007 ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE2007 | 2007
Sheng-Chung Yang; C. Chang; T. I. Yin
^{circ}{rm C}
Sensors and Actuators B-chemical | 2007
Shih-Ming Yang; T. I. Yin; C. Chang
</tex></formula>. In addition, HFET shows the significant hydrogen-detecting ability under an extremely low hydrogen concentration of 10-ppb <formula formulatype=inline><tex Notation=TeX>
Sensors and Actuators B-chemical | 2008
Shih-Ming Yang; C. Chang; T. I. Yin; P. L. Kuo
{rm H}_{2}/{rm N}_{2}
Sensors and Actuators B-chemical | 2011
Tai You Chen; Huey-Ing Chen; Yi Jung Liu; Chien Chang Huang; Chi Shiang Hsu; C. Chang; Wen-Chau Liu
</tex></formula>. Good transient responses are also observed even at room temperature. In addition, a small and nearly constant value of recovery time <formula formulatype=inline> <tex Notation=TeX>
Sensors and Actuators B-chemical | 2010
Sheng-Chung Yang; C. Chang
({approx}{rm 20}~{rm s})
Sensors and Actuators B-chemical | 2012
Chi Shiang Hsu; Huey-Ing Chen; C. Chang; Tai You Chen; Chien Chang Huang; Po Cheng Chou; Wen-Chau Liu
</tex></formula> is acquired when the hydrogen concentration is higher than 1-ppm <formula formulatype=inline><tex Notation=TeX>
