氧化硅中纳米晶硅薄膜的低温沉积及其键合特性研究

Low-temperature Deposition and Bonding Performance of Silicon Nanocrystals in Silicon Oxide Films

以Ar和H2为溅射气体,采用Si和SiO2双靶活性溅射技术实现了镶嵌纳米晶硅(nc-Si)的富硅氧化硅(SiOx)薄膜的300℃低温生长,并分析了氢气掺入对薄膜微观结构及键合特性的影响。结果表明,氢气流量比的增加导致纳米硅粒子尺寸增加,而生长速率逐渐减小。薄膜中Si-O键合结构以Si(O4)键为主,随H2流量比的增加,Si-O4-nSin(n=0,1)键密度减小,Si-O4-nSin(n=2,3)和SiH2键密度持续增加,而所对应Si-H键密度呈现先减小后增加趋势,该结果可解释为等离子体内氢原子对反应前驱物中氧的去除效应增强和氢原子与表面氧的解吸附反应几率的增加。

Silicon rich silicon oxide films(SiOx) containing nanocrystalline silicon(nc-Si) grains have been deposited at low substrate temperature of 300 ℃ using co-sputtering technique using Ar and H2 as sputtering gases.Then,the microstructure and bonding properties of the deposited films were analyzed.It revealed that the size nc-Si grains was enhancement and the deposition rate was reduced when the hydrogen flux ratio is increased.For the Si-O bonds,a concentration reduction was observed with the increase of hydrogen flux ratio for Si-O4-nSin(n =0,1) structures,while an inverse trend was for Si-O4-n Sin(n =2,3) and SiH2 structures,while for the Si-H bonds,an increase trend after an initial decrease was identified for SiH structure.All above results can be explained by the reactive hydrogen atoms increased the probability of reducing oxygen from precursor in the plasma and prompting oxygen desorption from the growing surface.