氧气对MWPCVD制备金刚石膜的影响

在水冷反应室式微波等离子体化学气相沉积装置中以混合的CH4/H2/O2为反应气体,研究了O2浓度对制备金刚石膜的影响.实验发现,很低浓度的O2会显著促进金刚石的沉积,并稍稍抑制非晶C的沉积,因而沉积膜中非晶C的含量急剧下降;较高浓度的O2会同时抑制金刚石和非晶C的沉积,但由于抑制金刚石的作用更强烈,沉积膜中非晶C的含量反而有所升高.另外,O2的存在,有利于沉积颗粒较小的金刚石膜.

Influence of O2 on Growth of Diamond Films by Microwave Plasma Chemical Vapor Deposition

Diamond films were synthesized from CH 4/H 2/O 2 gas mixture by microwave plasma chemical vapor deposition (MWPCVD) in a water cooled reaction chamber.Influence of O 2 concentration on the film growth was studied with laser Raman spectroscopy and scanning electron microscopy (SEM).The results show that very low O 2 concentration markedly promotes diamond film de position but slightly suppresses the amorphous carbon growth.Consequently,the content of amorphous carbon in the diamond films was drastically reduced.In contrast,higher O 2 concentration slows down the deposition of diamond more pronounced than that of amorphous carbon and results in higher content of amorphous carbon in the films.In addition,the existence of O 2 favorably affects the growth of diamond films with smaller grain sizes.