使用光发射谱(OES)对甚高频等离子增强化学气相沉积(VHF-PECVD)技术沉积硅薄膜时的等离子体发光基团的空间分布进行了在线监测和研究.研究表明:等离子体的不同发光基团都存在着一个中间强度较大的区域和两边电极附近的暗区;增大硅烷浓度和提高辉光功率都会增大SiH*峰强度;硼烷的加入,使得SiH*和Hα*峰强度增大,但硼烷流量变化的影响很小;硼烷流量增大,材料的晶化率下降,而I[Hα*]/I[SiH*]值却上升;当硅烷浓度改变时,空间各个区域内的I[Hα*]/I[SiH*]值的变化规律不同;而改变辉光功率或改变硼烷流量的情况下,空间各个点的I*/I*值变化规律都是相同的.
One-dimensional spatial distribution of the plasma luminous radicals during depositing silicon films and its online monitoring were studied using optical emission spectroscopy. The results indicated that there existed an evident luminous zone in the middle of the plasma and a dark zone near the two electrodes. The intensity of SiH* and Hα* peak increased with the increase of silane concentration, power, and the incorporation of borane. Crystalline volume fraction of thin films decreased with the increase of borane flow rate, but the ratio of I[Hα*]/I[SiH*] was also increased. The ratio of I[Hα*]/I[SiH*] varied in different ways at different positions with the variation of silane concentration. However, an unigue variation of the ratio all over the plasma is observed with the variation of the discharge power or the borane flow rate.