A Convenient and Effective Method to Deposit Low-Defect-Density nc-Si:H Thin Film by PECVD

Nanoscale Research Letters

Yuwei Wang¹  Hong Liu¹  Wenzhong Shen¹ 

[1] Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), Department of Physics and Astronomy, Shanghai Jiao Tong University;

关键词: Hydrogenated nanocrystalline silicon;    PECVD;    Deposition pressure;    Ion bombardment;    Defect density;   

DOI  :  10.1186/s11671-018-2641-z

来源: DOAJ

【 摘 要 】

Abstract Hydrogenated nanocrystalline silicon (nc-Si:H) thin film has received a great deal of attention as a promising material for flat panel display transistors, solar cells, etc. However, the multiphase structure of nc-Si:H leads to many defects. One of the major challenges is how to reduce the defects conveniently. In this work, we developed a simple and effective method to deposit low-defect-density nc-Si:H thin film. This method is simply by tuning the deposition pressure in a high-pressure range in plasma-enhanced chemical vapor deposition (PECVD) process. Microstructures of the nc-Si:H were characterized by Raman, AFM, and SEM. Furthermore, we focused on the defect density which was the key characteristic for photovoltaic materials and achieved the defect density of 3.766 × 1016 cm−3. This defect density is lower than that of previous studies on the fabrication of low-defect-density nc-Si:H by other complex methods in PECVD process. The minority carrier lifetime of nc-Si:H is thus greatly improved. Moreover, we demonstrated the mechanism about the effect of deposition pressure on the ion bombardment and proved that the defect density is the key characteristic for nc-Si:H photovoltaic material.

【 授权许可】

Unknown