非晶硅薄膜的镍离子注入研究

Study on Amorphous Silicon Film Doped by Ni Ion Implantation

为得到具有器件应用价值的非晶硅薄膜,首先采用等离子体增强化学气相沉积系统获得非晶硅薄膜,之后用离子注入设备对该薄膜进行镍离子注入掺杂。用椭偏仪测试薄膜厚度,得知非晶硅薄膜厚度为200nm,且沉积工艺稳定。X射线衍射仪测试表明,所沉积的薄膜属于完全非晶态。用四探针薄膜电阻测试设备测试非晶硅薄膜的方块电阻,结果表明,当掺杂浓度为2.5×1019个/cm3,离子注入能量为35.2 keV时,掺杂后的非晶硅薄膜具有较好电学性质,TCR约为-0.7%,室温下的方块电阻为992 kΩ/□。

In order to get good amorphous silicon film applicable for devices, amorphous silicon （α-Si：H） film was aquired by plasma enhanced chemical vapor deposition system （PECVD）. Then the film was doped by Ni ion implantation. The thickness of the film was measured by spectroscopic ellipsometry, which was about 200nm stably in the decided deposition parameters. XRD test shown that the film was completely amorphous. Square resistance of the doped film was tested by the four point probe test instrument finally. The result shows that, in Ni ion implantation parameters of 2.5×1019个/cm^3 and 35.2 keV, amorphous silicon film with good eleetronieal property is acquired. And TCR of the film is about -0.7%. And square resistance of the film is 992 kΩ/□ at room temperature.