プラズマにおける微粒子の成長過程と成長制御―基礎と応用―

抄録

Growth processes of particles in reactive plasmas have been studied mainly using SiH4 capacitively coupled HF discharges. In the SiH4 discharges, the particles grow to large ones through three phases: the initial growth phase including nucleation in the range of size below about 10 nm; the rapid growth phase in which particles grow due to coagulation between negatively and positively charged particles; the growth saturation phase in which almost all particles are charged negatively. The growth of particles (clusters) in the initial growth phase is characterized both by the time for neutral higher-order-silanes SinHx (n＜4) to grow up to a nucleation size n～ 4, and by that for them to be transported out of the bulk plasma by gas flow. The results of growth kinetics obtained for the SiH4 discharges until now have been applied to improving properties of devices such as amorphous silicon solar cells (growth suppression of clusters) , and also to fabricating new functional electronic devices by using not only SiH4 discharges but also and another material gas discharges (positive utilization of particles generated in plasmas by controlling their growth).