摘要
采用等离子体增强化学气相沉积(PECVD)技术,在玻璃衬底上低温沉积了优质本征和掺磷纳米硅薄膜,并利用Raman散射谱和电导率谱对比研究了磷掺杂对纳米硅薄膜的电子输运性质的影响。研究结果表明影响本征纳米硅电导率的主导因素是载流子的迁移率,而自由载流子浓度影响有限;影响掺磷纳米硅薄膜电导率的因素既包括磷掺杂产生的自由载流子,又包括迁移率,其输运过程可用量子点隧穿(HQD)模型合理解释。少量掺磷会促进晶化,但过量掺磷会引起晶格畸变,不利于晶化率和电导率的提高。
The intrinsic and phosphorus-doped nc-Si : H films which were deposited on glass substrate at low temperature through PECVD process and the effect of phosphorus doping on its transportability were comparably investigated by Raman and electrical conductivity spectra. The results showed that the mobility of free carriers is the key inluencing factor on the electrical conductivity of intrinsic nc-Si : H films but the effect of free carrier concentration is finite, while the free carrier concentration and mobility are both the main influencing factors on the electrical conductivity of phosphorus-doped nc-Si : H films. Its transportability can be reasonably explained by a HQD model. A bit of phosphorus doping is helpful to crystallization, but excessive doping may result in lattice distorsion that is unfavorable to improving crystallization rate and electrical conductivity.
出处
《真空》
CAS
北大核心
2007年第5期25-28,共4页
Vacuum
基金
国家重点基础研究发展计划(2006CB202601)资助
关键词
化学气相沉积
纳米硅
晶化率
电导率
量子点
nc-Si :H
PECVD
crystallization rate
electrical conductivity
HQD (hetero-quantum-dots)