Details

Autor(en) / Beteiligte

• Wang, Hung-Ta
• Anderson, T. J.
• Kang, B. S.
• Ren, F.
• Li, Changzhi
• Low, Zhen-Ning
• Lin, Jenshan
• Gila, B. P.
• Pearton, S. J.
• Osinsky, A.
• Dabiran, Amir

Titel

Stable hydrogen sensors from AlGaN∕GaN heterostructure diodes with TiB2-based Ohmic contacts

Ist Teil von

• Applied physics letters, 2007-06, Vol.90 (25)

Erscheinungsjahr

2007

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• The use of TiB2-based Ohmic contacts on Pt-gate AlGaN∕GaN heterostructure diode hydrogen sensors is shown to provide very stable operation for detection of 1% H2 in air under field conditions where temperature is allowed to vary. In contrast, the use of more conventional Ti∕Al∕Pt∕Au Ohmic contacts led to higher background variations in current that affect the ultimate detection threshold of the sensors. Combined with a differential pair geometry that compares current from an active diode with Pt-gate contact and a passive diode with Ti∕Au gate, the more stable TiB2-based Ohmic contacts reduce false alarms due to ambient temperature changes. The diodes exhibit a change in forward current of more than 1mA at 1.5V when 1% H2 is introduced into an air ambient.