Hydrogen-Sensing Characteristics of a Pd/GaN Schottky Diode With a Simple Surface Roughness Approach

作者：Chen Tai You^*; Chen Huey Ing; Huang Chien Chang; Hsu Chi Shiang; Chiu Po Shun; Chou Po Cheng; Liu Rong Chau; Liu Wen Chau

来源：IEEE Transactions on Electron Devices, 2011, 58(11): 4079-4086.

DOI：10.1109/TED.2011.2166269

• GaN
• Pd
• plasma treatment
• Schottky diode
• surface roughness

Hydrogen-sensing characteristics of a Pd/GaN Schottky diode with a simple surface roughness approach are studied and demonstrated. A high sensing response S(r) of 2.05 x 10(5) and a large Schottky barrier height variation ratio (Delta phi(B)/phi(air)) of 36.3% upon exposure to a 1% H(2)/air gas at 303 K are found. They could be attributed to the presence of more adsorption sites caused by the employed surface plasma treatment. The increase in series resistance due to the decrease in sensing response under the applied voltage range from 0.5 to 1 V is found. Based on the kinetic analysis and transient-state behavior measurement, at 523 K, the studied device shows a faster adsorption time of 2.9 s and a higher initial rate of 968 mu A/s. Consequently, the studied structure provides a promise for high-performance GaN-based Schottky-diode-type hydrogen sensor applications.

• 出版日期2011-11