在本論文中，我們研製一系列高性能化合物半導體式之氫氣感測器，包含蕭特基二極體、場效電阻器及異質場效電晶體。由於鈀和鉑對氫氣具有良好的觸媒活性，可用來當作感測金屬。砷化鎵、砷化鋁鎵和砷化銦鋁具有比矽材料較大的能隙，可用來當作感測平台。我們探討這些感測器在不同溫度下對不同濃度的氫氣之相關感測電性、偵測效能和動態表現。
首先，探討鉑/砷化銦鋁蕭特基二極體式感測器在不同溫度下的氫氣感測特性。此元件展現良好的感測性能，包含高相對靈敏度比、大電流變化量、寬廣的反向操作電壓區間及快速響應時間。探討順向及反向電壓的感測特性比較，提出一個簡單的模型來詮釋在順向及反向偏壓下的氫氣感測表現。從實驗結果得知，熱離子發射及場發射的機制對於氫氣感測特性具有極大的影響。
其次，利用鈀/氧化層/砷化鋁鎵擬晶性高電子移動率電晶體線性區的電流–電壓特性，我們研製一個三端型控制場效電阻式氫氣感測器。氫氣解離、氫原子擴散及電偶極層的形成造成通道電阻的有效減少。跟其它電阻式氫氣感測器相比，此元件展現重要的優點，在室溫下具有較低的偵檢極限及較高的靈敏度。此外，探討閘-源極電壓對氫氣感測特性的影響。
接著，利用砷化鎵/砷化鋁鎵異質結構及鈀觸媒閘極電極，研製場效電晶體來偵測氫氣靈敏度。對此元件而言，成長5 nm厚的帽層主要是抑制底下砷化鋁鎵層的氧化。我們探討並分析此感測元件的電流–電壓特性，平衡吸附跟動力吸附。反應焓及反應熵的負值暗示著氫氣吸附過程是放熱反應，而且氫原子更加有秩序地排列當它們吸附在鈀/砷化鎵的界面。另外，亦比較在空氣及氮氣環境中的氫氣感測特性來探討氧氣效應對此元件的影響。
最後，探討鈀/砷化鎵系列場效電晶體的氫氣誘導交換行為。我們觀察到截止區的氫氣偵測靈敏度具有劇烈的變化。為了更進一步了解鈀/砷化鎵電晶體式氫氣感測器的穩定性及可靠度，利用加速壽命測試此元件在高溫、高濃的感測表現，包含兩端及三端電性與動態響應。根據實驗結果，這些感測元件對於智慧型感測器及微機電系統應用具有良好之發展潛力。

In this dissertation, a series of high-performance compound semiconductor based hydrogen sensors, including Schottky diodes, field-effect resistors, and heterostructure field-effect transistors, are fabricated and studied. Pd and Pt are used as sensing metals due to their excellent catalytic activity towards hydrogen gas. GaAs, AlGaAs, and InAlAs materials are served as sensing platforms because of their larger band gap than that of Si-based materials. We present the related electric characteristics, detection performance, and dynamic behaviors of these sensors measured under different hydrogen concentrations at different temperatures.
First, the temperature-dependent hydrogen-detection characteristics of a Pt/InAlAs Schottky diode-type sensor are studied and demonstrated. The studied device exhibits significant sensing performance, including high relative sensitivity ratio, large current variation, widespread reverse voltage regime, and fast transient response time. A comparative study between forward and reverse biases is presented. A simple detection model is proposed to elucidate the hydrogen sensing behavior under forward and reverse biases. Thermionic emission (TE) and field emission (FE) exhibit considerable influences on the hydrogen sensing properties.
Second, a three-terminal-controlled field-effect resistive hydrogen sensor, based on the current-voltage characteristics in the linear region of a Pd/oxide/AlGaAs pseudomorphic high electron mobility transistor, is fabricated and studied. The dissociation of H2, diffusion of H atoms and formation of a dipolar layer cause a significant decrease in channel resistance. In comparison with other resistor-type hydrogen sensors, the studied device demonstrates the considerable advantages of lower detection limit and higher sensitivity at room temperature. In addition, the influences of gate-source bias (VGS) on the hydrogen sensing properties are presented.
Third, field-effect transistors based on GaAs/AlGaAs heterostructures are fabricated with catalytically active palladium (Pd) gate electrodes to induce the sensitivity of hydrogen gas. For the studied device, a 5 nm-thick undoped GaAs cap layer is grown to suppress the oxidation of the underneath Al0.24Ga0.76As layer. Comprehensive analysis on the electrical properties including equilibrium adsorption and kinetic adsorption is presented. The negative reaction enthalpy and entropy indicate that hydrogen adsorption process is exothermic and hydrogen atoms are more ordered when they are adsorbed at the Pd/GaAs interface. Hydrogen sensing characteristics in air and nitrogen environments are comparatively studied to investigate the influence of oxygen effect on the studied device.
Finally, hydrogen-induced switching behaviors of a Pd/GaAs-based field-effect transistor are studied. A drastic change of hydrogen detection sensitivity is observed in the cut-off region. To further understand the stability and reliability of the Pd/GaAs transistor-type hydrogen sensor, the accelerated lifetime-test sensing behaviors toward high hydrogen concentration at high temperature, including two- and three-terminal electrical characteristics and dynamic responses, are presented. Based on the experimental results, these studied devices provide the promise for smart hydrogen sensors and micro-electro-mechanical system (MEMS) applications.

[1] N. Yamazoe, “Toward innovations of gas sensor technology,” Sens. Actuators B, vol. 108, pp. 2-14, 2005.
[2] F. Favier, E. C. Walter, M. P. Zach, T. Benter, and R. M. Penner, “Hydrogen sensors and switches from electrodeposited palladium mesowire arrays,” Science, vol. 293, pp. 2227-2231, 2001.
[3] E. C. Walter, F. Favier, and R. M. Penner, “Palladium mesowire arrays for fast hydrogen sensors and hydrogen-actuated switches,” Anal. Chem., vol. 74, pp. 1546-1553, 2002.
[4] Z. Zhao, M. A. Carpenter, D. Welch, and H. Xia, “All-optical hydrogen sensor based on a high alloy content palladium thin film,” Sens. Actuators B, vol. 113, pp. 532-538, 2006.
[5] R. C. Weast, Handbook of Chemistry and Physics, CRC Press, Cleveland, 1976, pp. D-107.
[6] I. Lundström, S. Shivaraman, C. Svensson, and L. Lundkvist, “A hydrogen-sensitive MOS field-effect transistor,” Appl. Phys. Lett., vol. 26, pp. 55-57, 1975.
[7] K. I. Lundström, M. S. Shivaraman, and C. M. Svensson, “A hydrogen-sensitive Pd-gate MOS transistor,” J. Appl. Phys., vol. 46, pp. 3876-3881, 1975.
[8] E. F. MuCullen, H. E. Prakasam, W. Mo, R. Naik, K. Y. S. Ng, L. Rimai, and G. W. Auner, “Electrical characterization of metal/AlN/Si thin film hydrogen sensors with Pd and Al gates,” J. Appl. Phys., vol. 93, pp. 5757-5762, 2003.
[9] I. Lundström, H. Sundgren, F. Winquist, M. Eriksson, C. K. Rülcker, and A. L. Spetz, “Twenty-five years of field effect gas sensor research in Linköping,” Sens. Actuators B, vol. 121, pp. 247-262, 2007.
[10] C. Lu, Z. Chen, and K. Saito, “Hydrogen sensors based on Ni/SiO2/Si MOS capacitors,” Sens. Actuators B, vol. 122, 556-559, 2007.
[11] D. E. Williams, “Semiconducting oxides as gas-sensitive resistors,” Sens. Actuators B, vol. 57, pp. 1-16, 1999.
[12] B. Chwieroth, B. R. Patton, and Y. Wang, “Conduction and gas-surface reaction modeling in metal oxide gas sensors,” J. Electroceram. Soc., vol. 6, pp. 27-41, 2001.
[13] P. F. Ruths, S. Ashok, S. J. Fonash, and J. M. Ruths, “A study of Pd/Si MIS Schottky barrier diode hydrogen detector,” IEEE Trans. Electron Devices, vol. 28, pp. 1003-1009, 1981.
[14] A. Trinchi, W. Wlodarski, and Y. X. Li, “Hydrogen sensitive Ga2O3 Schottky diode sensor based on SiC,” Sens. Actuators B, vol. 100, pp. 94-98, 2004.
[15] C. Wilbertz, H. P. Frerichs, I. Freund, and M. Lehmann, “Suspended-gate- and Lundstrom-FET integrated on a CMOS chip,” Sens. Actuators B, vol. 123-124, pp. 2-6, 2005.
[16] K. Tsukada, T. Kiwa, T. Yamaguchi, S. Migitaka, Y. Goto, and K. Yokosawa, “A study of fast response characteristics for hydrogen sensing with platinum FET sensor,” Sens. Actuators B, vol. 114, 158-163, 2006.
[17] K. W. Lin and R. H. Chang, “Comprehensive study of pseudomorphic high electron mobility transistor (pHEMT)-based hydrogen sensor,” Sens. Actuators B, vol. 119, 47-51, 2006.
[18] H. Y. Nie and Y. Nannichi, “Pd-on-GaAs Schottky contact: Its barrier height and response to hydrogen,” Jpn. J. Appl. Phys., vol. 30, pp. 906-913, 1991.
[19] L. M. Lechuga, A. Calle, D. Golmayo, P. Tejedor, and F. Briones, “A new hydrogen sensor based on a Pt/GaAs Schottky diode,” Sens. Actuators B, vol. 4, pp. 515-518, 1991.
[20] W. P. Kang and Y. Gürbüz, “Comparison and analysis of Pd- and Pt-GaAs Schottky diodes for hydrogen detection,” J. Appl. Phys., vol. 75, pp. 8175-8181, 1994.
[21] W. C. Liu, H. J. Pan, H. I. Chen, K. W. Lin, and C. K. Wang, “Comparative hydrogen-sensing study of Pd/GaAs and Pd/InP metal-oxide-semiconductor Schottky diodes,” Jpn. J. Appl. Phys., vol. 40, pp. 6254-6259, 2001.
[22] A. Salehi, A. Nikfarjam, and D.J. Kalantari, “Pd/porous-GaAs Schottky contact for hydrogen sensing application,” Sens Actuators B, vol. 113, pp. 419-427, 2006.
[23] S. Y. Cheng, “A hydrogen sensitive Pd/GaAs Schottky diode sensor,” Mater. Chem. Phys., vol. 78, pp. 525-528, 2003.
[24] W. C. Liu, H. J. Pan, H. I. Chen, K. W. Lin, S. Y. Cheng, and K. H. Yu, “Hydrogen sensitive characteristics of a novel Pd/InP MOS Schottky diode hydrogen sensor,” IEEE Trans. Electron Devices, vol. 48, pp. 1938-1944, 2001.
[25] H. J. Pan, K. W. Lin, K. H. Yu, C. C. Cheng, K. B. Thei, W. C. Liu, and H. I. Chen, “Highly hydrogen-sensitive Pd/InP metal-oxide-semiconductor Schottky diode hydrogen sensor,” IEE Electron. Lett., vol. 38, pp. 92-94, 2002.
[26] H. I. Chen, Y. I. Chou, and C. Y. Chu, “A novel high-sensitive Pd/InP hydrogen sensor fabricated by electroless plating,” Sens. Actuators B, vol. 85, pp. 10-18, 2002.
[27] H. I. Chen and Y. I. Chou, “A comparative study of hydrogen sensing performance between electroless plated and thermal evaporated Pd/InP Schottky diodes,” Semicond. Sci. Technol., vol. 18, pp. 104-110, 2003.
[28] H. I. Chen, Y. I Chou, and C. K. Hsiung, “Comprehensive study of adsorption kinetics for hydrogen sensing with an electroless-plated Pd-InP Schottky diode,” Sens. Actuators B, vol. 92, pp. 6-16, 2003.
[29] H. I. Chen and Y. I. Chou, “Evaluation of the perfection of the Pd-InP Schottky interface from the energy viewpoint of hydrogen adsorbates,” Semicond. Sci. Technol., vol. 19, pp. 39-44, 2004.
[30] Y. I. Chou, C. M. Chen, W. C. Liu, and H. I. Chen, “A novel Pd-InP Schottky hydrogen sensor fabricated by electrophoretic deposition with Pd nanoparticles,” IEEE Electron Device Lett., vol. 26, pp. 62-65, 2005.
[31] T. Kimura, H. Hasegawa, T. Sato, and T. Hashizume, “Sensing mechanism of InP hydrogen sensors using Pt Schottky diodes formed by electrochemical process,” Jpn. J. Appl. Phys., vol. 45, pp. 3414-3422, 2006.
[32] W. C. Liu, K. W Lin, H. I. Chen, C. K. Wang, C. C. Cheng, S. Y. Cheng, and C. T. Lu, “A new Pt/Oxide/In0.49Ga0.51P MOS Schottky diode hydrogen sensor,” IEEE Electron Device Lett., vol. 23, pp. 640-642, 2002.
[33] K. W. Lin, H. I. Chen, H. M. Chuang, C. Y. Chen, and W. C. Liu, “A hydrogen sensing Pd/InGaP metal-semiconductor (MS) Schottky diode hydrogen sensor,” Semicond. Sci. Technol., vol. 18, pp. 615-619, 2003.
[34] K. W. Lin, H. I. Chen, C. C. Cheng, H. M. Chuang, C. T. Lu, and W. C. Liu, “Characteristics of a new Pt/oxide/In0.49Ga0.51P hydrogen-sensing Schottky diode,” Sens. Actuators B, vol. 94, pp. 145-151, 2003.
[35] K. W. Lin, H. I. Chen, H. M. Chuang, C. Y. Chen, C. T. Lu, C. C. Cheng, and W. C. Liu, “Characteristics of Pd/InGaP Schottky diodes hydrogen sensors,” IEEE Sensors J., vol. 4, pp. 72-79, 2004.
[36] C. T. Lu, K. W. Lin, H. I. Chen, H. M. Chuang, C. Y. Chen, and W. C. Liu, “A new Pd-Oxide-Al0.3Ga0.7As MOS hydrogen sensor,” IEEE Electron Device Lett., vol. 24, pp. 390-392, 2003.
[37] Y. Y. Tsai, K. W. Lin, C. T. Lu, H. I. Chen, H. M. Chuang, C. Y. Chen, C. C. Cheng, and W. C. Liu, “Investigation of hydrogen-sensing properties of Pd/AlGaAs-based Schottky diodes,” IEEE Trans. Electron Devices, vol. 50, pp. 2532-2539, 2003.
[38] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. I. Chen, C. T. Lu, and W. C. Liu, “Hydrogen sensing characteristics of a Pt-oxide-Al0.3Ga0.7As MOS Schottky diode,” Sens. Actuators B, vol. 99, pp. 425-430, 2004.
[39] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. I. Chen, W. H. Hsu, H. M. Chuang, C. Y. Chen, and W. C. Liu, “Hydrogen sensing characteristics of Pd- and Pt-Al0.3Ga0.7As metal–semiconductor (MS) Schottky diodes,” Semicond. Sci. Technol., vol. 19, pp. 778-782, 2004.
[40] C. W. Hung, H. L. Lin, H. I. Chen, Y. Y. Tsai, P. H. Lai, S. I. Fu, and W. C. Liu, “A novel Pt/In0.52Al0.48As Schottky diode-type hydrogen sensor,” IEEE Electron Device Lett., vol. 27, pp. 951-954, 2006.
[41] C. W. Hung, T. H. Tsai, Y. Y. Tsai, K. W. Lin, H. I. Chen, T. P. Chen, and W. C. Liu, “A hydrogen sensor based on an InAlAs material with a Pt catalytic thin film,” Phys. Scr., vol. T129, pp. 345-348, 2007.
[42] C. W. Hung, T. H. Tsai, H. I. Chen, Y. Y. Tsai, T. P. Chen, L. Y. Chen, K. Y. Chu, and W. C. Liu, “Temperature-dependent hydrogen sensing characteristics of a new Pt/InAlAs Schottky diode-type sensor,” Sens. Actuators B, vol. 128, pp. 574-580, 2008.
[43] J. Schalwig, G. Müller, U. Karrer, M. Eickhoff, O. Ambacher, M. Stutzmann, L. Görgens, and G. Dollinger, “Hydrogen response mechanism of Pt-GaN Schottky diodes,” Appl. Phys. Lett., vol. 80, pp. 1222-1224, 2002.
[44] B. S. Kang, S. Kim, F. Ren, B. P. Gila, C. R. Abernathy, and S. J. Pearton, “Comparison of MOS and Schottky W/Pt-GaN diodes for hydrogen detection,” Sens. Actuators B, vol. 104, pp. 232-236, 2005.
[45] J. R. Huang, W. C. Hsu, Y. J. Chen, T. B. Wang, K. W. Lin, H. I. Chen, and W. C. Liu, “Comparison of hydrogen sensing characteristics for Pd/GaN and Pd/Al0.3Ga0.7As Schottky diodes,” Sens. Actuators B, vol. 117, pp. 151-158, 2006.
[46] J. R. Huang, W. C. Hsu, H. I. Chen, and W. C. Liu, “Comparative study of hydrogen sensing characteristics of a Pd/GaN Schottky diodes, “Sens Actuators B, vol. 123, pp. 1040-1048, 2007.
[47] J. Song, W. Lu, J. S. Flynn, and G. R. Brandes, “AlGaN/GaN Schottky diode hydrogen sensor performance at high temperatures with different catalytic metals,” Solid-State Electron., vol. 49, pp. 1330-1334, 2005.
[48] H. Hasegawa and M. Akazawa, “Hydrogen sensing characteristics and mechanism of Pd/AlGaN/GaN Schottky diodes subjected to oxygen gettering,” J. Vac. Sci. Technol. B, vol. 25, pp. 1495-1503, 2007.
[49] H. T. Wang, T. J. Anderson, B. S. Kang, F. Ren, C. Li, Z. N. Low, J. Lin, B. P. Gila, S. J. Pearton, A. Osinsky, and A. Dabiran, “Stable hydrogen sensors from AlGaN/GaN heterostructure diodes with TiB2-based Ohmic contacts,” Appl. Phys. Lett., vol. 90, pp. 252109, 2007.
[50] M. Miyoshi, Y. Kuraoka, K. Asai, T. Shibata, and M. Tanaka, “Electrical characterization of Pt/AlGaN/GaN Schottky diodes grown using AlN template and their application to hydrogen gas sensors,” J. Vac. Sci. Technol. B, vol. 25, pp. 1231-1235, 2007.
[51] H. Hasegawa and M. Akazawa, “Mechanism and control of current transport in GaN and AlGaN Schottky barriers for chemical sensor applications,” Appl. Surf. Sci., vol. 254, pp. 3653-3666, 2008.
[52] S. Basu and A. Dutta, “Room-temperature hydrogen sensors based on ZnO,” Mater. Chem. Phys., vol. 47, pp. 93-96, 1997.
[53] T. Hyodo, N. Nishida, Y. Shimizu, and M. Egashira, “Preparation and gas-sensing properties of thermally stable mesoporous SnO2,” Sens. Actuators B, vol. 83, pp. 209-215, 2002.
[54] W. J. Moon, J. H. Yu, and G. M. Choi, “The CO and H2 gas selectivity of CuO-doped SnO2-ZnO composite gas sensor,” Sens. Actuators B, vol. 87, pp. 464-470, 2002.
[55] O. K. Varghese, D. Gong, M. Paulose, K. G. Ong, and C. A. Grimes, “Hydrogen sensing using titania nanotubes,” Sens. Actuators B, vol. 93, pp. 338-344, 2003.
[56] J. Wöllenstein, M. Burgmair, G. Plescher, T. Sulima, J. Hildenbrand, H. Böttner, and I. Eisele, “Cobalt oxide based gas sensors on silicon substrate for operation at low temperatures,” Sens. Actuators B, vol. 93, pp. 442-448, 2003.
[57] S. Aygün and D. Cann, “Hydrogen sensitivity of doped CuO/ZnO heterocontact sensors,” Sens. Actuators B, vol. 106, pp. 837-842, 2005.
[58] K. S. Yoo, S. H. Park, and J. H. Kang, “Nano-grained thin-film indium tin oxide gas sensors for H2 detection,” Sens. Actuators B, vol. 108, pp. 159-164, 2005.
[59] C. A. Grimes, “Synthesis and application of highly ordered arrays of TiO2 nanotubes,” J. Mater. Chem., vol. 17, pp. 1451-1457, 2007.
[60] S. Shukla, P. Zhang, H. J. Cho, S. Seal, and L. Ludwig, “Room temperature hydrogen response kinetics of nano-micro-integrated doped tin oxide sensor,” Sens. Actuators B, vol. 120, pp. 573-583, 2007.
[61] Y. Shimizu, T. Hyodo, and M. Egashira, “H2 sensing performance of anodically oxidized TiO2 thin films equipped with Pd electrode,” Sens. Actuators B, vol. 121, pp. 219-230, 2007.
[62] S. Shukla, P. Zhang, H. J. Cho, L. Ludwig, and S. Seal, “Significance of electrode-spacing in hydrogen detection for tin oxide-based MEMS sensor,” Int. J. Hydrog. Energy, vol. 33, pp. 470-475, 2008.
[63] M. Jaegle and K. Steiner, “Gas-sensitive GaAs-MESFETs,” Sens. Actuators B, vol. 34, pp. 543-547, 1996.
[64] J. Li, D. Petelenz, and J. Janata, “Suspended gate field effect transistor sensitive to gaseous hydrogen cyanide,” Electroanal., vol. 5, pp. 791-794, 1993.
[65] K. Scharnagl, M. Eriksson, A. Karthigeyan, M. Burgmair, M. Zimmer, and I. Eisele, “Hydrogen detection at high concentrations with stabilised palladium,” Sens. Actuators B, vol. 78, pp. 138-143, 2001.
[66] Z. Gergintschew, P. Kornetzky, and D. Schipanski, “The capacitively controlled field effect transistor (CCFET) as a new low power gas sensor,” Sens. Actuators B, vol. 36, pp. 285-289, 1996.
[67] K. W. Lin, C. C. Cheng, S. Y. Cheng, K. H. Yu, C. K. Wang, H. M. Chuang, J. Y. Chen, C. Z. Wu, and W. C. Liu, “A novel Pd/oxide/GaAs metal–insulator–semiconductor field-effect transistor (MISFET) hydrogen sensor,” Semicond. Sci. Technol., vol. 16, pp. 997-1001, 2001.
[68] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. I. Chen, W. H. Hsu, C. W. Hong, and W.C. Liu, “Temperature-dependent hydrogen sensing characteristics of a Pd/oxide/Al0.24Ga0.76As high electron mobility transistor (HEMT),” IEE Electron. Lett., vol. 40, pp. 1608-1609, 2004.
[69] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. L. Chen, and W. C. Liu, “Hydrogen sensing properties of a Pt-oxide-Al0.24Ga0.76As high-electron-mobility transistor,” Appl. Phys. Lett., vol. 86, pp. 112103, 2005.
[70] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. I. Chen, W. H. Hsu, C. W. Hong, H. L. Lin, and W. C. Liu, “Study of hydrogen-sensing characteristics of a Pt-oxide-AlGaAs metal-oxide-semiconductor high electron mobility transistor,” J. Vac. Sci. Technol. B, vol. 23, pp. 1943-1947, 2005.
[71] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. I. Chen, W. H. Hsu, C. W. Hong, and W. C. Liu, “Characteristics of a Pd-oxide-In0.49Ga0.51P high electron mobility transistor (HEMT)-based hydrogen sensor,” Sens. Actuators B, vol. 113, pp. 29-35, 2006.
[72] C. W. Hung, H. L. Lin, Y. Y. Tsai, P. H. Lai, S. I. Fu, H. I. Chen, and W. C. Liu, “AlGaAs/InGaAs/GaAs transistor-based hydrogen sensing device grown by metal organic chemical vapor deposition,” Jpn. J. Appl. Phys., vol. 45, pp. 680-684, 2006.
[73] C. C. Cheng, Y. Y. Tsai, K. W. Lin, H. I. Chen, W. H. Hsu, C. W. Hung, R. C. Liu, and W. C. Liu, “Pd-oxide-Al0.24Ga0.76As (MOS) high electron mobility transistor (HEMT)-based hydrogen sensor,” IEEE Sensors J., vol. 6, pp. 287-292, 2006.
[74] C. W. Hung, H. L. Lin, H. I. Chen, Y. Y. Tsai, P. H. Lai, S. I. Fu, H. M. Chuang, and W. C. Liu, “Comprehensive study of a Pd-GaAs high electron mobility transistor (HEMT)-based hydrogen sensor,” Sens. Actuators B, vol. 122, pp. 81-88, 2007.
[75] C. W. Hung, K. W. Lin, R. C. Liu, Y. Y. Tsai, P. H. Lai, S. I. Fu, T. P. Chen, H. I. Chen, and W. C. Liu, “On the hydrogen sensing properties of a Pd/GaAs transistor-type gas sensor in a nitrogen ambiance,” Sens. Actuators B, vol. 125, pp. 22-29, 2007.
[76] C. W. Hung, H. I. Chen, T. H. Tsai, C. F. Chang, T. P. Chen, L. Y. Chen, K. Y. Chu, and W. C. Liu, “Hydrogen-induced effect on device performance of a Pd/GaAs-basd heterostructure field-effect transistor (HFET),” J. Electrochem. Soc., vol. 155, pp. H243-H246, 2008.
[77] J. Schalwig, G. Müller, M. Eickhoff, O. Ambacher, and M. Stutzmann, “Gas sensitive GaN/AlGaN-heterostructures,” Sens. Actuators B, vol. 87, pp. 425-430, 2002.
[78] S. Nakagomi, A. Fukumura, Y. Kokubun, S. Savage, H. Wingbrant, M. Andersson, I. Lundström, M. Löfdahl, and A. L. Spetz, “Influence of gate bias of MISiC-FET gas sensor device on the sensing properties,” Sens Actuators B, vol. 108, pp. 501-507, 2005.
[79] B. S. Kang, R. Mehandru, S. Kim, F. Ren, R. C. Fitch, J. K. Gillespie, N. Moser, G. Jessen, T. Jenkins, R. Dettmer, D. Via, A. Crespo, B. P. Gila, C. R. Abernathy, and S. J. Pearton, “Hydrogen-induced reversible changes in drain current in Sc2O3/AlGaN/GaN high electron mobility transistors,” Appl. Phys. Lett., vol. 84, pp. 4635-4637, 2004.
[80] H. T. Wang, B. S. Kang, F. Ren, R. C. Fitch, J. K. Gillespie, N. Moser, G. Jessen, T. Jenkins, R. Dettmer, D. Via, A. Crespo, B. P. Gila, C. R. Abernathy, and S. J. Pearton, “Comparison of gate and drain current detection of hydrogen at room temperature with AlGaN/GaN high electron mobility transistors,” Appl. Phys. Lett., vol. 87, 172105, 2005.
[81] J. Suehiro, S. I. Hidaka, S. Yamane, and K. Imsaka, “Fabrication of interfaces between carbon nanotubes and catalytic palladium using dielectrophoresis and its application to hydrogen gas sensor,” Sens. Actuators B, vol. 127, pp. 505-511, 2007.
[82] O. Weidemann, M. Hermann, G. Steinhoff, H. Wingbrant, A. L. Spetz, M. Stutzmann, and M. Eickhoff, “Influence of surface oxides on hydrogen-sensitive Pd:GaN Schottky diodes,” Appl. Phys. Lett., vol. 83, pp. 773-775, 2003.
[83] J. P. Xu, P. T. Lai, B. Han, and W .M. Tang, “Determination of optimal insulator thickness for MISiC hydrogen sensors, Solid-State Electron., vol. 48, pp. 1673-1677, 2004.
[84] M. Eriksson, A. Salomonsson, I. Lundström, D. Briand, and A. E. Åbom, “The influence of the insulator surface properties on the hydrogen response of field-effect gas sensors,” J. Appl. Phys., vol. 98, pp. 034903, 2005.
[85] T. H. Tsai, J. R. Huang, K. W. Lin, C. W. Hung, H. I. Chen, and W. C. Liu, “Improved hydrogen sensing properties of a Pt/SiO2/GaN Schottky diode,” Electrochem. Solid State Lett., vol. 10, pp. J158-J160, 2007.
[86] D. Li, A. H. McDaniel, R. Bastasz, and J. W. Medlin, “Effects of a polyimide coating on the hydrogen selectivity of MIS sensors,” Sens. Actuators B, vol. 115, pp. 86-92, 2006.
[87] L. M. Lechuga, A. Calle, D. Golmayo, and F. Briones, “Different catalytic metals (Pt, Pd, and Ir) for GaAs Schottky barrier sensors,” Sens. Actuators B, vol. 7, pp. 614-618, 1992.
[88] M. Löfdahl, M. Eriksson, M. Johansson, and I. Lundström, “Difference in hydrogen sensitivity between Pt and Pd field-effect devices,” J. Appl. Phys., vol. 91, pp. 4275-4280, 2002.
[89] M. Armgarth and C. Nylander, “Blister formation in Pd gate MIS hydrogen sensors,” IEEE Electron Device Lett., vol. 3, pp. 384-386, 1982.
[90] M. Z. Atashbar, D. Banerji, and S. Singamaneni, “Room-temperature hydrogen sensor based on palladium nanowires,” IEEE Sensors J., vol. 5, pp. 792-797, 2005.
[91] K. Luongo, A. Sine, and S. Bhansali, “Development of a highly sensitive porous Si-based hydrogen sensor using Pd nano-structures,” Sens. Actuators B, vol. 111-112, pp. 125-129, 2005..
[92] F. Rahimi and A. Irajizad, “Effective factors on Pd growth on porous silicon by electroless-plating: Response to hydrogen,” Sens. Actuators B, vol. 115, pp. 164-169, 2006.
[93] K. T. Kim, S. J. Sim, and S. M. Cho, “Hydrogen gas sensor using Pd nanowires electro-deposited into anodized alumina template,” IEEE Sensors J., vol. 6, pp. 509-513, 2006.
[94] P. K. Sekhar, A. Sine, and S. Bhansali, “Effect of varying the nanostructured porous-Si process parameters on the performance of Pd-doped hydrogen sensor,” Sens. Actuators B, vol. 127, pp. 74-81, 2007.
[95] H. Grönbeck, D. Tománek, S. G. Kim, and A. Rosén, “Hydrogen induced melting of Palladium clusters,” Z. Phys. D, vol. 40, 469-471, 1997.
[96] O. Dankert and A. Pundt, “Hydrogen-induced percolation in discontinuous films,” Appl. Phys. Lett., vol. 81, pp. 1618-1620, 2002.
[97] R. R. Blanchard, J. A. del Alamo, S. B. Adams, P. C. Chao, and A. Cornet, “Hydrogen-induced piezoelectric effects in InP HEMT,” IEEE Electron Device Lett., vol. 20, pp. 393-395, 1999.
[98] R. Duś, R. Nowakowski, and E. Nowicka, “Chemical and structural components of work function changes in the process of palladium hydride formation within thin Pd film,” J. Alloy. Compd., vol. 404-406, pp. 284-287, 2005.
[99] J. Chevallier, W. C. D. Smith, C. W. Tu, and S. J. Pearton, “Donor neutralization in GaAs(Si) by atomic hydrogen,” Appl. Phys. Lett., vol. 47, pp. 108-110, 1985.
[100] W. Gao, A. Khan, P. R. Berger, R. G. Hunsperger, G. Zydzik, H. M. O’Bryan, D. Sivco, and A. Y. Cho, “In0.53Ga0.47As metal-semiconductor-metal photodiodes with transparent cadmium tin oxide Schottky contacts,” Appl. Phys. Lett., vol. 65, pp. 1930-1932, 1994.
[101] W. C. Hsu, Y. J. Chen, C. S. Lee, T. B. Wang, J. C. Huang, D. H. Huang, K. H. Su, Y. S. Lin, and C. L. Wu, “Characteristics of In0.425Al0.575As/InxGa1-xAs metamorphic HEMTs with pseudomorphic and symmetrically-graded channels,” IEEE Trans. Electron Devices, vol. 52, pp. 1079-1086, 2005.
[102] J. C. Huang, W. C. Hsu, C. S. Lee, Y. J. Chen, D. H. Huang, and H. H. Chen, “Investigations of delta-doped InAlAs/InGaAs/InP high-electron-mobility transistors with linearly graded InxGa1-xAs channel,” Jpn. J. Appl. Phys., vol. 44, pp. 8305-8308, 2005.
[103] H. Ohno, C. E. C. Wood, L. Rathbun, D. V. Morgan, G. W. Wicks, and L. F. Eastman, “GaInAs-AlInAs structure grown by molecular beam epitaxy,” J. Appl. Phys., vol. 52, pp. 4033-4037, 1981.
[104] L. P. Sadwick, C. W. Kim, K. L. Tan, and D. C. Streit, “Schotky barrier heights of n-type and p-type Al0.48In0.52As,” IEEE Electron Device Lett., vol. 12, pp. 626-628, 1991.
[105] C. L. Lin, P. Chu, A. L. Kellner, H. H. Wieder, and E. A. Rezek, “Composition dependence of Au/InxAl1-xAs Schottky barrier heights,” Appl. Phys. Lett., vol. 49, pp. 1593-1595, 1986.
[106] H. F. Chuang, C. P. Lee, C. M. Tsai, D. C. Liu, J. S. Tsang, and J. C. Fan, “Thermal annealing of Pd/InAlAs Schottky contacts for transistor buried-gate technologies,” J. Appl. Phys., vol. 83, pp. 366-371, 1998.
[107] M. Ali, V. Cimalla, V. Lebedev, H. Romanus, V. Tilak, D. Merfeld, P. Sandvik, and O. Ambacher, “Pt/GaN Schottky diodes for hydrogen gas sensors,” Sens. Actuators B, vol. 113, pp. 797-804, 2006.
[108] H. Norde, “A modified forward I-V plot for Schottky diodes with high series resistance,” J. Appl. Phys., vol. 50, pp. 5052-5053, 1979.
[109] S. M. Sze, Physics of Semiconductor Devices, 2nd ed. New York: Wiley, 1981, Ch. 2.
[110] E. D. Palic and R. F. Wallis, “Infrared cyclotron resonance in n-type InAs and InP,” Phys. Rev., vol. 123, pp. 131-134, 1961.
[111] D. J. Stukel and R. N. Euwema, “Energy-band structure of aluminum arsenide,” Phys. Rev., vol. 188, pp. 1193-1196, 1969.
[112] W. Gao, P. R. Berger, R. G. Hunsperger, G. Zydzik, W. W. Rhodes, H. M. O’Bryan, D. Sivco, and A. Y. Cho, “Transparent and opaque Schottky contacts on undoped In0.52Al0.48As grown by molecular beam epitaxy,” Appl. Phys. Lett., vol. 66, pp. 3471-3473, 1995.
[113] E. H. Rhoderick and R. H. Williams, Metal-Semiconductor Contacts, in Monographs in Electrical and Electronic Engineering, 2nd ed. P. Hammond and R. L. Grimsdale, Eds. Oxford, U.K.: Clarendon, 1988.
[114] S. A. Khan, E. A. de Vasconcelos, H. Uchida, and T. Katsube, “Gas response and modeling of NO-sensitive thin-Pt SiC Schottky diodes,” Sens. Actuators B, vol. 92, pp. 181-185, 2003.
[115] M. Armgarth, D. Söderberg, and I. Lundström, “Palladium and platinum gate metal-oxide-semiconductor capacitors in hydrogen and oxygen mixtures,” Appl. Phys. Lett., vol. 41, pp. 654-655, 1982.
[116] L. G. Petersson, H. M. Dannetun, and I. Lundström, “The water-forming reaction on palladium,” Surf. Sci., vol. 161, pp. 77-100, 1985.
[117] L. G. Petersson, H. M. Dannetun, and I. Lundström, “Water production on palladium in hydrogen-oxygen atmospheres,” Surf. Sci., vol. 163, pp. 273-284, 1985.
[118] L. M. Lechuga, A. Calle, D. Golmayo, and F. Briones, “The ammonia sensitivity of Pt/GaAs Schottky barrier diodes,” J. Appl. Phys., vol. 70, pp. 3348-3354, 1991.
[119] C. Christofides and A. Mandelis, “Solid-state sensors for trace hydrogen gas detection,” J. Appl. Phys., vol. 68, pp. 1-30, 1990.
[120] A. Dittmar and K. Najafi, “Special topic section on microtechniques, microsensors, microactuators, and microsystems,” IEEE Trans. Biomed. Eng., vol. 47, pp. 1-2, 2000.
[121] R. C. Hughes and W. K. Schubert, “Thin films of Pd/Ni alloys for detection of high hydrogen concentrations,” J. Appl. Phys., vol. 71, pp. 542-544, 1992.
[122] S. Basu and A. Dutta, “Modified heterojunction based on zinc-oxide thin-film for hydrogen gas-sensor application,” Sens. Actuators B, vol. 22, pp. 83-87, 1994.
[123] Y. G. Choi, G. Sakai, K. Shimanoe, N. Miura, and N. Yamazoe, “Wet process-prepared thick films of WO3 for NO2 sensing,” Sens. Actuators B, vol. 95, pp. 258-265, 2003.
[124] J. Mizsei, “H2-induced surface and interface potentials on Pd-activated SnO2 sensor films,” Sens Actuators B, vol. 28, pp. 129-133, 1995.
[125] U. S. Choi, G. Sakai, K. Shimanoe, and N. Yamazoe, “Sensing properties of SnO2-Co3O4 composites to CO and H2,” Sens. Actuators B, vol. 98, pp. 166-173, 2004.
[126] Y. Shimizu, F. C. Lin, Y. Takao, and M. Egashira, “Zinc oxide varistor gas sensors: II, effect of chromium (III) oxide and yttrium oxide additives on the hydrogen-sensing properties,” J. Am. Ceram. Soc., vol.81, pp. 1633-1643, 1998.
[127] T. J. Fawcett, J. T. Wolan, R. L. Myers, J. Walker, and S. E. Saddow, “Wide-range (0.33%—100%) 3C-SiC resistive hydrogen gas sensor development,” Appl. Phys. Lett., vol. 85, pp. 416-418, 2004.
[128] F. Yun, S. Chevtchenko, Y. T. Moon, H. Morkoc, T. J. Fawcett, and J. T. Wolan, “GaN resistive hydrogen gas sensors,” Appl. Phys. Lett., vol. 87, pp. 073507, 2005.
[129] I. Sayago, E. terrado, E. Lafuente, M. C. Horrillo, W. K. Master, A. M. Benito, R. Navarro, E. P. Urriolabeitia, M. T. Martinez, and J. Gutierrez, “Hydrogen sensors based on carbon nanotubes thin films,” Synth. Metals, vol. 148, pp. 15-19, 2005.
[130] Y. L. Lai, E. Y. Chang, C. Y. Chang, T. K. Chen, T. H. Liu, S. P. Wang, T. H. Chen, and C. T. Lee, “5mm High-Power-Density Dual-Delta-Doped Power HEMTS for 3V L-Band Applications,” IEEE Electron Device Lett., vol. 17, pp. 229-231, 1996.
[131] Y. W. Chen, W. C. Hsu, H. M. Shieh, Y. J. Chen, Y. S. Lin, Y. J. Li, and T. B. Wang, “High breakdown characteristic -doped InGaP/InGaAs/AlGaAs tunneling real space transfer HEMT,” IEEE Trans. Electron Devices, vol. 49, pp. 221-225, 2002.
[132] S. W. Tan, M. K. Hsu, A. H. Lin, M. Y. Chu, W. T. Chen, and W. S. Lour, “Sub-0.25 micro gate like heterojunction doped-channel FETs with a controllable notch-angle V-gate,” Semicond. Sci. Technol., vol. 19, pp. 384-388, 2004.
[133] S. E. Gunnarsson, C. Kärnfelt, H. Zirath, R. Kozhuharov, D. Kuylenstierna, A. Alping, and C. Fager, “Highly integrated 60 GHz transmitter and receiver MMICs in a GaAs pHEMT technology,” IEEE J. Solid-State Circuits, vol. 40, pp. 2174-2186, 2005.
[134] T. L. Poteat and B. Lalevic, “Transition metal-gate MOS gaseous detectors,” IEEE Trans. Electron Devices, vol. 29, pp. 123-129, 1982.
[135] K. W. Lee, P. W. Sze, Y. H. Wang, and M. P. Houng, “AlGaAs/InGaAs metal-oxide-semiconductor pseudomorphic high-electron-mobility transistor with a liquid phase oxidized AlGaAs as gate dielectric,” Solid-State Electron., vol. 49, pp. 213-217, 2005.
[136] E. Souteyrand, D. Nicolas, and J. R. Martin, “Semiconductor/metal/gas behavior through surface-potential change,” Sens. Actuators B, vol. 24-25, pp. 871-875, 1995.
[137] S. M. Sze, Semiconductor Devices: Physics and Technology, 2nd ed. New York: Wiley, 1985, pp. 248.
[138] P. Mitra, A. P. Chatterjee, and H. S. Maiti, “ZnO thin film sensor,” Mater. Lett., vol. 35, pp. 33-38, 1998.
[139] D. Davazoglou and T. Dritsas, “Fabrication and calibration of a gas sensor based on chemically vapor deposited WO3 films on silicon substrates: Application to H2 sensing,” Sens. Actuators B, vol. 77, pp. 359-362, 2001.
[140] Y. Y. Tsai, K. W. Lin, H. I. Chen, C. T. Lu, H. M. Chuang, C. Y. Chen, and W. C. Liu, “Comparative hydrogen sensing performance of Pd- and Pt-InGaP metal-oxide-semiconductor Schottky diodes,” J. Vac. Sci. Technol. B, vol. 21, pp. 2471-2477, 2003.
[141] Y. Morita, K. I. Nakamura, and C. Kim, “Langmuir analysis on hydrogen gas response of palladium-gate FET,” Sens. Actuators B, vol. 33, pp. 96-99, 1996.
[142] A. Spetz, M. Armgarth, and I. Lundström, “Hydrogen and ammonia response of metal-silicon dioxide-silicon structures with thin platinum gate,” J. Appl. Phys., vol. 64, pp. 1274-1283, 1988.
[143] M. Johansson, I. Lundström, and L. G. Ekedahl, “Bridging the pressure gap for palladium metal/insulator/semiconductor hydrogen sensors in oxygen containing environments,” J. Appl. Phys., vol. 84, pp. 44-51, 1998.
[144] J. Fogelberg and L.G. Ekedahl, “Kinetic modeling of the H2O2 reaction on Pd and its influence on the hydrogen response of a hydrogen sensitive Pd metal oxide/semiconductor,” Surf. Sci., vol. 350, pp. 91-102, 1996.
[145] D. N. Jewett and A. C. Makrides, “Diffusion of hydrogen through palladium and palladium-silver alloy,” J. Chem. Soc. Faraday Trans., vol. 61, pp. 932-939, 1965.
[146] W. S. Lour, M. K. Tsai, K. C. Chen, Y. W. Wu, S. W. Tan, and Y. J. Yang, “Dual-gate In0.5Ga0.5P/In0.2Ga0.8As pseudomorphic high electron mobility transistors with high linearity and variable gate-voltage swing,” Semicond. Sci. Technol., vol. 16, pp. 826-830, 2001.
[147] C. S. Lee and W. C. Hsu, “Bias-tunable multiple-transconductance with improved transport characteristics of δ-doped In0.28Ga0.72As/GaAs/In0.24Ga0.76As/GaAs high electron mobility transistor using a graded superlattice spacer,” Jpn. J. Appl. Phys., vol. 42, pp. 1545-1547, 2003.
[148] P. H. Lai, S. I. Fu, Y. Y. Tsai, C. H. Yen, S. Y. Cheng, and W. C. Liu, “Characteristics of a sulfur-passivated InGaP/InGaAs/GaAs heterostructure field-effect transistor,” Appl. Phys. Lett., vol. 87, pp. 083502, 2005.
[149] S. Kim, H. Noh, K. Jang, J. H. Lee, and K. Seo, “High performance 0.1 μm GaAs pseudomorphic high electron mobility transistors with Si pulse-doped cap layer for 77 GHz car radar applications,” Jpn. J. Appl. Phys., vol. 44, pp. 2472-2475, 2005.
[150] M. Kudo, T. Mishima, and M. Washima, “Highly strained InGaAs layers on GaAs grown by molecular beam epitaxy for high electron mobility transistors,” J. Cryst. Growth, vol. 150, pp. 1236-1240, 1995.
[151] X. Cao, Y. Zeng, M. Kong, L. Pan, B. Wang, Z. Zhu, X. Wang, Y. Chang, and J. Chu, “Photoluminescence of AlGaAs/InGaAs/GaAs pseudomorphic HEMTs with different thickness of spacer layer,” J. Cryst. Growth, vol. 231, pp. 520-524, 2001.
[152] A. Z. Li, Y. Q. Chen, J. X. Chen, M. Qi, X. C. Liu, J. Chen, R. M. Wang, W. L. Wang, and W. X. Li, “High-performance enhancement-mode pseudomorphic InGaP/InGaAs/GaAs HEMT structures by gas source molecular beam epitaxy,” J. Cryst. Growth, vol. 251, pp. 816-821, 2003.
[153] N. Yanazoe, J. Fuchigami, M. Kishikawa, and T. Seiyama, “Interactions of tin oxide surface with O2, H2O and H2,” Surf. Sci., vol. 86, pp. 335-344, 1979.
[154] E. D. Bartolomeo, N. Kaabbuathong, M. L. Grilli, and E. Traversa, “Planar electrochemical sensors based on tape-cast YSZ layers and oxide electrodes,” Solid State Ionics, vol. 171, pp. 173-181, 2004.
[155] M. Krawczyk and J. Namiesnik, “Application of a catalytic combustion sensor (Pellistor) for the monitoring of the explosiveness of a hydrogen-air mixture in the upper explosive limit range,” J. Autom. Methods Manag. Chem., vol. 25, pp. 115-122, 2003.
[156] D. Soderberg and I. Lundström, “Surface and interface dipoles on catalytic metal films,” Solid State Commun., vol. 35, pp. 169-174, 1980.
[157] B. Y. Tsui and C. F. Huang, “Wide range work function modulation of binary alloys for MOSFET application,” IEEE Electron Device Lett., vol. 24, pp. 153-155, 2003.
[158] L. M. Lechuga, A. Calle, D. Golmayo, and F. Briones, “A new hydrogen sensor based on a Pt/GaAs Schottky diode,” J. Electrochem. Soc., vol. 138, pp. 159-162, 1991.
[159] C. S. Lee and W. C. Hsu, “Double-transconductance-plateau characteristics in InGaAs/GaAs real-space transfer high-electron-mobility transistor,” Appl. Phys. Lett., vol. 84, pp. 3618-3820, 2004.
[160] Y. S. Lin, W. C. Hsu, H. M. Shieh, and C. Y. Yeh, “In0.34Al0.66As0.85Sb0.15/d(n+)-InP heterostructure field-effect transistors,” Appl. Phys. Lett., vol. 76, pp. 3124-3126, 2000.
[161] K. J. Laidler and J. H. Meiser, Physical Chemistry, Boston: Houghton Mifflin, 1995, pp. 385.
[162] R. J. Silbey and R. A. Alberty, Physical Chemistry, 3rd ed., Wiley, New York, 2001.
[163] P. C. Chao, M. Y. Kao, K. Nordheden, and A. W. Swanson, “HEMT degradation in hydrogen gas,” IEEE Electron Device Lett., vol. 15, pp. 151-153, 1994.
[164] A. S. Sedra and K. C. Smith, Microelectronic Circuits, 4th Ed., Oxford University Press, New York , 1998, Ch. 5.
[165] C. W. Hung, H. C. Chang, Y. Y. Tsai, P. H. Lai, S. I. Fu, T. P. Chen, H. I. Chen, and W. C. Liu, “Study of a new field-effect resistive hydrogen sensor based on a Pd/oxide/AlGaAs transistor,” IEEE Trans. Electron Devices, vol. 52, pp. 1224-1231, 2007.
[166] I. Sayago, J. Gutiérrez, L. Arés, J. I. Robla, M. C. Horrillo, J. Getino, J. Rino, and J. A. Agapito, “Long-term reliability of sensors for detection of nitrogen oxides,” Sens. Actuators B, vol. 26-27, pp. 56-58, 1995.
[167] I. Gràcia, J. Santander, C. Cané, M. C. Horrillo, I. Sayago, and J. Gutierrez, “Results on the reliability of silicon micromachined structures for semiconductor gas sensors,” Sens. Actuators B, vol. 77, pp. 409-415, 2001.
[168] J. M. Bosc, Y. Guo, V. Sarihan, and T. Lee, “Accelerated life testing for micro-machined chemical sensors,” IEEE Trans. Reliab., vol. 47, pp. 135-141, 1998.
[169] R. K. Sharma, P. C. H. Chan, Z. Tang, G. Yan, I. M. Hsing, and J. K. O. Sin, “Investigation of stability and reliability of tin oxide thin-film for integrated micro-machined gas sensor devices,” Sens. Actuators B, vol. 81, pp. 9-16, 2001.
[170] I. Lunström, “Hydrogen sensitive MOS-structure. Part 1: Principles and applications,” Sens. Actuators, vol. 1, pp. 403-426, 1981.
[171] S. M. Sze, Physics of Semiconductor Devices, 2nd ed. New YorK: Wiley, 1990, pp. 341.
[172] T. Sands, V. G. Keramidas, R. Gronsky, and J. Washburn, “Initial stages of the Pd-GaAs reaction: Formation and decomposition of ternary phases,” Thin Solid Films, vol. 136, pp. 105-122, 1986.
[173] D. Filippini and I. Lundström, “Hydrogen detection on bare SiO2 between metal gates,” J. Appl. Phys., vol. 91, pp. 3896-3903, 2002.
[174] D. Söderberg and I. Lundström, “Competition between hydrogen and oxygen dissociation on palladium surface at atmospheric pressures,” Solid State Commun., vol. 45, pp. 431-434, 1983.
[175] T. Kobiela and R. Dus, “STM/AFM studies of the catalytic reaction of oxygen with hydrogen on the surface of thin palladium film,” Vacuum, vol. 63, pp. 267-276, 2001.