氢气稀释比例对多晶硅薄膜微观结构和沉积特性的影响  

Insights into the deposition rate and microstructure of polysilicon films: effect of different hydrogen dilution ratio

作　　者：宋莎莎[1] 左潇[1] 魏钰[1] 陈龙威[1] 舒兴胜[1] 

机构地区：[1]中国科学院等离子体物理研究所,合肥230031

出　　处：《核聚变与等离子体物理》2014年第3期275-281,共7页Nuclear Fusion and Plasma Physics

摘　　要：利用电感耦合等离子体增强化学气相沉积法(ICP-PECVD)直接在普通玻璃衬底上低温沉积多晶硅薄膜,主要研究了不同氢气稀释比例对薄膜沉积特性和微观结构的影响。采用X射线衍射仪(XRD)、拉曼光谱仪和扫描电子显微镜(SEM)表征了在不同氢气比例条件下所制备多晶硅薄膜的微结构、形貌,并对不同条件下样品的沉积速率进行了分析。实验结果表明:随着混合气体中硅烷比例的增加,薄膜的沉积速率不断增加;晶化率先增加,后减小;当硅烷含量为4.8%时,晶化率达到最大值67.3%。XRD和SEM结果显示多晶硅薄膜在普通玻璃衬底上呈柱状生长,且晶粒排列整齐、致密,这种结构可提高载流子的纵向迁移率,有利于制备高效多晶硅薄膜太阳能电池。Polycrystalline silicon thin film formation from inductively coupled plasma enhanced chemical vapor deposition system was studied. The dilution effect of H2 on film deposition was discussed. The X-ray diffractometry, Raman spectra and scanning electron microscope measurement were carried out to analyze the influence of H2 on the microstructures and the topography of polycrystalline silicon thin films. The optimum conditions for polycrystalline silicon thin films deposition were also discussed. The results indicated that polycrystalline silicon thin films with columnar structure crystals were fabricated on glass substrate. The deposition rate exhibited monotonic increase with Silane ratio R, a maximum deposition rate of 0.65nm·s-1 was obtained. However, the crystal volume fraction of polycrystalline silicon thin films initially increased from 60.5%to 67.3%, and then slightly decreased with the increase of R. Therefore, the crystal has a maximum value of 67.3%at R=4.8%. The polycrystalline silicon thin films had a compact and well-arranged structure at this ratio. This structure can also increase carrier mobility and improve the efficiency of solar cells.

关 键 词：电感耦合等离子体 等离子体增强化学气相沉积 多晶硅薄膜 氢气比例 

分 类 号：O539[理学—等离子体物理]