摘要Pt/AlGaN/AlN/GaN Schottky diodes are fabricated and characterized for hydrogen sensing. The Pt Schottky contact and the Ti/Al/Ni/Au ohmic contact are formed by evaporation. Both the forward and reverse currents of the device increase greatly when exposed to hydrogen gas. A shift of 0.3V at 300K is obtained at a fixed forward current after switching from N2 to 10%H2+N2. The sensor responses under different concentrations from 50ppm H2 to 10%H2+N2 at 373K are investigated. Time dependences of the device forward current at 0.5V forward bias in N2 and air atmosphere at 300 and 373K are compared. Oxygen in air accelerates the desorption of the hydrogen and the recovery of the sensor. Finally, the decrease of the Schottky barrier height and sensitivity of the sensor are calculated.
Abstract：Pt/AlGaN/AlN/GaN Schottky diodes are fabricated and characterized for hydrogen sensing. The Pt Schottky contact and the Ti/Al/Ni/Au ohmic contact are formed by evaporation. Both the forward and reverse currents of the device increase greatly when exposed to hydrogen gas. A shift of 0.3V at 300K is obtained at a fixed forward current after switching from N2 to 10%H2+N2. The sensor responses under different concentrations from 50ppm H2 to 10%H2+N2 at 373K are investigated. Time dependences of the device forward current at 0.5V forward bias in N2 and air atmosphere at 300 and 373K are compared. Oxygen in air accelerates the desorption of the hydrogen and the recovery of the sensor. Finally, the decrease of the Schottky barrier height and sensitivity of the sensor are calculated.
WANG Xin-Hua;WANG Xiao-Liang;FENG Chun;XIAO Hong-Ling;YANG Cui-Bai;WANG Jun-Xi;WANG Bao-Zhu;RAN Jun-Xue; WANG Cui-Mei. Hydrogen Sensors Based on AlGaN/AlN/GaN Schottky Diodes[J]. 中国物理快报, 2008, 25(1): 266-269.
WANG Xin-Hua, WANG Xiao-Liang, FENG Chun, XIAO Hong-Ling, YANG Cui-Bai, WANG Jun-Xi, WANG Bao-Zhu, RAN Jun-Xue, WANG Cui-Mei. Hydrogen Sensors Based on AlGaN/AlN/GaN Schottky Diodes. Chin. Phys. Lett., 2008, 25(1): 266-269.
[1] Asif Khan M, Bhattarai A, Kuznia J N et al 1993 Appl. Phys.Lett. 63 1214 [2] Miyoshi M, Ishikawa H, Egawa T et al 2004 Appl. Phys. Lett. 85 1710 [3] Wang X L, Wang C M, Hu G X et al 2006 Phys. Status Solidi C 3 607 [4] Pearton S J,Kang B S,Kim S et al 2004 J. Phys.: Condens.Matter 16 R961 [5] Luther B P, Wolter S D, Mohney S E 1999 Sens. Actuators B 56 164 [6] Schalwig J, M\"uller G, Eickhoff M et al 2002 Mater. Sci.Eng. B 93 207 [7] Steinhoff G, Hermann M, Schaff W J et al 2003 Appl. Phys.Lett. 83 177 [8] Eickhoff M,Schalwig J,Steinhoff G et al 2003 Phys. StatusSolidi C 6 1908 [9] Kim J, Gila B P,Abernathy C R et al 2003 Solid StateElectron. 47 1487 [10] Song J, Lu W, Flynn J S et al 2005 Appl. Phys. Lett. 87 133501-1 [11] Matsuo K, Negoro N, Kotani J et al 2005 Appl. Surf. Sci. 244 273 [12] Huang J R, Hsu W Ch, Chen Y J et al 2006 SensorsActuators B 117 151 [13] Hasegawa H. 2007 Curr. Appl. Phys. 7 318 [14] Wang C M, Wang X L, Hu G X et al 2006 J. Cryst. Growth 289 415 [15] Wang X L, Hu G X, Ma Z Y et al 2007 J. Cryst. Growth 298 835 [16] Ma Z Y, Wang X L, Hu G X et al 2007 Chin. Phys. Lett. 24 1705 [17] Voss L, Gila B P, Pearton S J et al 2005 J. Vac. Sci.Technol. B 23 2373 [18] Sze S M 1981 Physics of Semiconductor Devices 2nd edn (NewYork: Wiley) chap 2 [19] Kim J,Ren F,Gila B P et al 2003 Appl. Phys. Lett. 82 739 [20] Kang B S, Mehandru R, Kim S et al 2005 Phys. Status Solidi C 2 2672
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