Title :
Characteristics of Pd/InGaP Schottky diodes hydrogen sensors
Author :
Lin, Kun-Wei ; Chen, Huey-Ing ; Chuang, Hung-Ming ; Chen, Chun-Yuan ; Lu, Chun-Tsen ; Cheng, Chin-Chuan ; Liu, Wen-Chau
Author_Institution :
Dept. of Electr. Eng., Nat. Cheng-Kung Univ., Taiwain, Taiwan
Abstract :
Pd/InGaP hydrogen sensors based on the metal-oxide-semiconductor (MOS) and metal-semiconductor Schottky diodes have been fabricated and systematically studied. The effects of hydrogen adsorption on device performances such as the current-voltage characteristics, barrier height variation, hydrogen coverage, and heat of adsorption are investigated. The studied devices exhibit very wide hydrogen concentration detection regimes and remarkable hydrogen-sensing properties. Particularly, an extremely low hydrogen concentration of 15 ppm H2/air at room temperature can be detected. In addition, under the presence of oxide layers in the studied MOS device structure, the enhancements of barrier height and high-temperature operating capability are observed. The initial heat of adsorption for Pd/oxide and Pd/semiconductor interface are calculated as 355 and 65.9 meV/atom, respectively. Furthermore, the considerably short response times are found in studied devices.
Keywords :
III-V semiconductors; Schottky diodes; gas sensors; Fermi-level pinning; MOS device; Pd-InGaP; Pd-InGaP Schottky diodes hydrogen sensors; adsorption heat; barrier height variation; current-voltage characteristics; hydrogen adsorption; hydrogen concentration detection; hydrogen coverage; hydrogen-sensing properties; metal-oxide-semiconductor Schottky diode; metal-semiconductor Schottky diode; semiconductor interface; FETs; Gallium arsenide; Hydrogen; Schottky barriers; Schottky diodes; Semiconductor diodes; Sensor phenomena and characterization; Sensor systems; Temperature measurement; Temperature sensors;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2003.820320
