掺杂nc-Si:H薄膜中纳米硅晶粒的择优生长

发现PECVD生长的系列掺杂氢化纳米硅(nc-Si:H)薄膜中纳米硅晶粒(nc-Si)有择优生长的趋势.用Raman、XRD、AFM、HRTEM等方法研究其微观结构时发现:掺磷的nc-Si:H薄膜XRD 峰位的二倍衍射角约为33°.掺硼nc-Si:H薄膜的XRD峰位的二倍衍射角约为47°.用自由能密度与序参量的关系结合实验参数分析得到:较高的衬底温度引起序参量改变,使掺磷nc-Si:H薄膜中nc-Si的晶面择优生长.适当的电场作用引起序参量改变,导致掺硼nc-Si:H薄膜在一定的自由能密度范围内nc-Si的晶面择优生长.

Preferred growth of nanosized crystal silicon in doped hydrogenated nanocrystalline silicon film

The preferred growth of nanosized crystal silicon (nc-Si) in doped hydrogenated nanocrystalline silicon (nc-Si:H) films which were prepared using plasma enhanced chemical vapor deposition (PECVD) system by RF(13.56?MHz) and DC bias stimulating was found. Its microstructure was investigated using X-ray diffraction (XRD), Raman spectrum meter, atomic force microscope (AFM) and high resolution transmission electronic microscope (HRTEM). Nc-Si about 10 nm was distributed in the silicon-hydrogen amorphous networks in the films. The peaks of XRD spectra of phosphorus doped nc-Si:H films was at 2θ≈33°, the exponent of crystalline plane was (130). The peaks of XRD spectra of boron doped nc-Si:H films was at 2θ≈47°, the exponent of crystalline plane was (220), respectively. The considerable reasons were investigated. The relation between size of nc-Si, crystalline volume fraction and depositing parameters were studied.