C. Chang

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

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.

Hydrogen-Sensing Properties of a Pd/AlGaN/GaN-Based Field-Effect Transistor Under a Nitrogen Ambience

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>

Ammonia Sensing Properties of a Pt/AlGaN/GaN Schottky Diode

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Measurement of DNA Hybridization by Nano-Deformation of Microcantilever in CMOS Biosensor

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On the temperature compensation of parallel piezoresistive microcantilevers in biosensors

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Development of a double-microcantilever for surface stress measurement in microsensors

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DNA hybridization measurement by self-sensing piezoresistive microcantilevers in CMOS biosensor

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Ammonia sensing characteristics of a Pt/AlGaN/GaN Schottky diode

</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>

A piezoresistive bridge-microcantilever biosensor by CMOS process for surface stress measurement

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On the hydrogen sensing characteristics of a Pd/AlGaN/GaN heterostructure field-effect transistor (HFET)

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