C元素对N型a-Si∶H薄膜微结构及电学特性的影响  

Influence of Carbon on Microstructure and Electrical Properties of N-type a-Si∶H Films

作　　者：金鑫[1] 李伟[2] 蒋亚东[2] 廖乃镘[2] 陈宇翔[1] 陈德鹅[1] 

机构地区：[1]电子科技大学光电信息学院,成都610054 [2]电子科技大学电子薄膜与集成器件国家重点实验室,成都610054

出　　处：《半导体光电》2009年第5期715-718,723,共5页Semiconductor Optoelectronics

摘　　要：采用等离子增强化学气相沉积(PECVD)工艺,制备了P-C二元复合掺杂氢化非晶硅(a-Si∶H)薄膜,研究了C元素对N型a-Si∶H薄膜暗电导率(σ)及电导激活能(Ea)的影响;利用激光拉曼光谱研究了C元素对薄膜微结构的影响,讨论了P-C二元复合掺杂a-Si∶H薄膜电学性能与微结构之间的相互影响关系。结果表明:随着C掺杂量的增加,a-Si∶H薄膜的短程有序度降低,中程有序度基本保持不变,缺陷逐渐减少;一定程度的C掺杂可使N型a-Si∶H薄膜电导激活能降低而使薄膜的暗电导率升高,但过量的C掺杂使N型a-Si∶H薄膜非晶网络结构有序度严重恶化,电导率出现明显下降趋势。Hydrogenated amorphous silicon （a-Si ： H） thin films doped with P and C were deposited by plasma enhanced chemical vapor deposition （PECVD）. The influence of carbon on the dark conductivity, activation energy and mirostructure of the P-doped a-Si ： H films was investigated by means of electrical measurment and Raman spectroscopy, and the relationship between electrical properties and microstructure of the films was also analyzed. It is shown from Raman spectra that the degree of short-range order and the defects of the films decreae with the increase of carbon doping, while the degree of intermediate-range order remains unchanged. A small amount of carbon can reduce the activation energy and enhance the dark conductivity of the P-doped a-Si ： H thin films. However, excessive carbon makes the structural order of the amouphous network get worse which leads to a decline of dark conductivity.

关 键 词：PECVD 氢化非晶硅薄膜 P—C复合掺杂 微结构 暗电导率 

分 类 号：TN484.1[电子电信—微电子学与固体电子学]