CAJ | 학술논문

以化学气相沉积法成长多晶金刚石薄膜时,薄膜的品质会受到成长时间、成长压力、反应气体比例、偏压与否及成核的机制等因素影响.研究采用微波电浆辅助化学气相沉积(MPECVD)法,以甲烷(CH4)和氢气(H2)作为反应气体原料,在P型(111)硅基板沉积多晶金刚石薄膜.典型沉积多晶金刚石薄膜的制程可分为四个阶段:抛蚀表面阶段、渗碳阶段、偏压增强成核(BEN)阶段及成长阶段.研究将成长阶段划分为两个阶段,第一阶段压力较低(成长Ⅰ阶段),第二阶段压力较高(成长Ⅱ阶段).结果表明:第一阶段可大大改善金刚石薄膜的品质,所获多晶金刚石薄膜的晶粒具有明确的颗粒边界、较低的碳化物或缺陷,电导率急剧降低,显现出本徵金刚石半绝缘的性质.可以认为金刚石薄膜品质的改善完全为低压成长所致.实验发现在成长Ⅰ阶段或成长Ⅱ阶段施加偏压时,只会降低多晶金刚石薄膜的品质.
이화학기상침적법성장다정금강석박막시,박막적품질회수도성장시간、성장압력、반응기체비례、편압여부급성핵적궤제등인소영향.연구채용미파전장보조화학기상침적(MPECVD)법,이갑완(CH4)화경기(H2)작위반응기체원료,재P형(111)규기판침적다정금강석박막.전형침적다정금강석박막적제정가분위사개계단:포식표면계단、삼탄계단、편압증강성핵(BEN)계단급성장계단.연구장성장계단화분위량개계단,제일계단압력교저(성장Ⅰ계단),제이계단압력교고(성장Ⅱ계단).결과표명:제일계단가대대개선금강석박막적품질,소획다정금강석박막적정립구유명학적과립변계、교저적탄화물혹결함,전도솔급극강저,현현출본징금강석반절연적성질.가이인위금강석박막품질적개선완전위저압성장소치.실험발현재성장Ⅰ계단혹성장Ⅱ계단시가편압시,지회강저다정금강석박막적품질.
The quality of polycrystalline diamond films grown by chemical vapor deposition is dependent on the growth time, pressure, carbon-to-hydrogen ratio, bias, and nucleation mechanism involved. In this study, reaction gases, methane (CH4) and hydrogen (H2), were used to grow polycrystalline diamond on a p-type (111) silicon substrate with a microwave plasma-enhanced chemical vapor deposition system. In addition to the conventional etching, bias-en-hanced nucleation, and growth steps, the growth step was further divided into two stages. The first stage (growth Ⅰ) was carried out at low pressure and the second (growth Ⅱ) was carried out at high pressure. Results clearly indicate that the use of the growth Ⅰ stage can considerably improve the quality of the diamond film. In the growth Ⅰ stage, well-faceted grains with lower contents of graphite and carbide, and fewer defects are obtained. Therefore, the conductivity is drasti-cally decreased by nearly two orders of magnitude and the diamond film exhibits the semi-insulating characteristics of in-trinsic diamond. The improvement is caused solely by the addition of the low-pressure growth Ⅰ stage. Application of bi-as in the growth Ⅰand/or growth Ⅱ stages can only degrade the synthesized polycrystalline diamond film.