Temperature dependent interfacial and electrical characteristics during atomic layer deposition and annealing of HfO_2 films in p-GaAs metal–oxide–semiconductor capacitors  

作　　者：刘琛 张玉明 张义门 吕红亮 芦宾 

机构地区：[1]School of Microelectronics and Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices, Xidian University

出　　处：《Journal of Semiconductors》2015年第12期87-90,共4页半导体学报（英文版）

基　　金：supported by the Advance Research Project of China(No.5130803XXXX);the National Natural Science Foundation of China(No.61176070)

摘　　要：We have investigated the temperature dependent interfacial and electrical characteristics of p-GaAs metal-oxide-semiconductor capacitors during atomic layer deposition （ALD） and annealing of HfO2 using the tetrakis （ethylmethyl） amino hafnium precursor. The leakage current decreases with the increase of the ALD tem- perature and the lowest current is obtained at 300 ℃ as a result of the Frenkel-Poole conduction induced leakage current being greatly weakened by the reduction of interfacial oxides at the higher temperature. Post deposition annealing （PDA） at 500 ℃ after ALD at 300 ℃ leads to the lowest leakage current compared with other annealing temperatures. A pronounced reduction in As oxides during PDA at 500 ℃ has been observed using X-ray pho- toelectron spectroscopy at the interface resulting in a proportional increase in Ga203. The increment of Ga203 after PDA depends on the amount of residual As oxides after ALD. Thus, the ALD temperature plays an important role in determining the high-k/GaAs interface condition. Meanwhile, an optimum PDA temperature is essential for obtaining good dielectric properties.We have investigated the temperature dependent interfacial and electrical characteristics of p-GaAs metal-oxide-semiconductor capacitors during atomic layer deposition （ALD） and annealing of HfO2 using the tetrakis （ethylmethyl） amino hafnium precursor. The leakage current decreases with the increase of the ALD tem- perature and the lowest current is obtained at 300 ℃ as a result of the Frenkel-Poole conduction induced leakage current being greatly weakened by the reduction of interfacial oxides at the higher temperature. Post deposition annealing （PDA） at 500 ℃ after ALD at 300 ℃ leads to the lowest leakage current compared with other annealing temperatures. A pronounced reduction in As oxides during PDA at 500 ℃ has been observed using X-ray pho- toelectron spectroscopy at the interface resulting in a proportional increase in Ga203. The increment of Ga203 after PDA depends on the amount of residual As oxides after ALD. Thus, the ALD temperature plays an important role in determining the high-k/GaAs interface condition. Meanwhile, an optimum PDA temperature is essential for obtaining good dielectric properties.

关 键 词：GaAs metal-oxide-semiconductor capacitor TEMPERATURE interface leakage current 

分 类 号：TM53[电气工程—电器]