辉光功率对n型a-Si:H薄膜结构及性能的影响

Effect of Discharge Power on Structure and Properties of n-typed a-Si:H Thin Films

采用射频等离子增强化学气相沉积（RF-PECVD）方法,以氢稀释的硅烷（SiH4）为反应气体,磷烷（PH3）为掺杂气体,制备了n型氢化非晶硅（a-Si：H）薄膜。研究了辉光放电功率对薄膜微结构和光电性能的影响,采用XRD和拉曼散射光谱对薄膜的微结构进行了表征,薄膜的折射率通过NKD-7000 W光学薄膜系统拟合,薄膜暗电导率利用高阻仪测试。结果表明：在辉光功率30-150 W范围内,所沉积的磷掺杂的硅薄膜为非晶态;非晶态薄膜结构中程有序度随辉光功率的增大先增大后减小,在功率为100 W时非晶硅薄膜中程有序程度最高;薄膜的折射率随着辉光功率的增大先增加后减小,在功率为70 W达到最大值3.7;薄膜暗电导率在100 W最大,其最大值为9.32×10^-3S/cm。

Phosphorus doped hydrogenated amorphous silicon（a-Si∶H） thin films were fabricated by radio frequency plasma enhanced chemical vapor deposition（RF-PECVD）,SiH4 and PH3 with high hydrogen dilution are used as the reactive gas and dopant gas,respectively.The microstructure of the films was studied by Raman spectra and XRD.The refraction index was simulated by NKD-7000W System Spectrophotometer.Dark conductivity of the films with different discharge power was measured by high Electrometer.The results showed that the phosphorus doped Si thin films were amorphous as the discharge power in the range of 30-150 W.The ordering of amorphous network on the intermediate scales and refraction index of the thin films increased firstly and then decreased as the discharge power increasing,the ordering of amorphous network thin films is the best at the power of 100 W and the maximum of refraction index of thin films at the power of 70 W is 3.7.The maximum value of dark conductivity of the films at the power of 100 W was 9.32×10-3 S/cm.