Ga在SiO_2-Si复合结构中的热分布研究

Investigation of Thermal Distribution of Ga in SiO_2/Si Structure

用 H2 和 Ga_2O_3的高温反应形成元素 Ga 的恒定表面源,通过 SiO_2-Si 复合结构实现了 Ga 在 Si 中的高均匀性掺杂;利用二次离子质谱分析(SIMS)、扩展电阻(SRP)、四探针测试等方法,对 P 型杂质 Ga 在 SiO_2薄膜、SiO_2-Si 两固相接触的内界面、近 Si 表面的热分布进行分析;揭示出开管方式扩散 Ga 的实质是由 SiO_2薄膜对 Ga 原子的快速输运及其在 SiO_2-Si 内界面分凝效应两者统一的必然结果;并对该过程 Ga 杂质浓度分布机理进行了分析和讨论。

The high temperature reaction between H-2 and Ga2O3 is employed to obtain constant surface source of Ga, then high uniformity doping of Ga in Si is realized through SiO2-Si compound structure. By characterizing means of SIMS, SRP and four-point probe meter, the thermal distribution of P-type dopant Ga in SiO2 films, at the internal surface Of SiO2-Si and near Si surface is analyzed respectively. The essence of open-tube Ga diffusion is revealed, which is closely related with both the rapid transportation of Ga through SiO2 film and the segregation effect of it at the internal surface Of SiO2-Si. The mechanism of Ga concentration distribution is discussed accordingly.