Hydrogen response mechanism of Pt–GaN Schottky diodes

Abstract

Besides silicon carbide, group-III nitrides are also suitable large-band-gap semiconductor materials for high-temperature gas sensor devices. Exposing GaN-based Schottky diodes with catalytically active platinum electrodes to hydrogen, we observed a decrease of the rectifying characteristics which we attribute to a decrease in Schottky barrier height. Current–voltage and elastic recoil detection measurements were used to investigate the H-sensing behavior of such devices. Our results indicate an interfacial effect as the origin of the sensor response to hydrogen.

Pt Schottky diode gas sensors formed on GaN and AlGaN/GaN heterostructure

“…GaN-related materials with wide energy gaps maintain semiconducting properties at high temperatures, making them suitable for sensors operating at high-temperatures. However, only few works have been reported on GaN gas sensors [1,2] with an unclear sensing mechanism. This paper investigates H 2 gas-sensing characteristics of Pt/GaN and Pt/AlGaN/GaN Schottky diodes.…”

Hydrogen Response of Pd Schottky Diodes Formed on AlGaN/GaN Heterostructure

“…For these reasons, they are potentially suited to sensor application in addition to blue/UV photonic applications and high-power heterostructure field effect transistor (HFET) application. In fact, there are several reports on GaN-based hydrogen sensors [3][4][5]. Among them, we investigated the Pt Schottky diode-type H 2 gas sensor formed on the AlGaN/GaN heterostructure surface in view of possible integration of sensors with HFET circuits on the same chip.…”

Catalytic metal-gate field effect transistors based on SiC for indoor air quality control

“…V DS is utilized to measure the response to the target gas (Lloyd Spetz et al, 2013b). The study, evaluation, and choice of the catalytic material and its support (the gate dielectric) are important because the electrical performance of FET sensor devices as well as the chemical reactions responsible for the gas response depend on the type and nanostructure of the sensing layer processed onto the device , in conjunction with the nature and quality of the gate insulator (Schalwig et al, 2002;Eriksson et al, 2005).…”