本文選題：金剛石膜 + 微波等離子體化學(xué)氣相沉積�。� 參考：《昆明理工大學(xué)》2017年碩士論文

【摘要】：金剛石膜具有優(yōu)異的物理化學(xué)性能,如熱膨脹系數(shù)和摩擦系數(shù)低、禁帶寬度大、耐磨性優(yōu)良、紅外線透過率高、生物兼容性好,在光學(xué)、電學(xué)、生物學(xué)、機(jī)械領(lǐng)域具有廣泛的應(yīng)用前景,其制備工藝和功能化應(yīng)用已成為當(dāng)前材料科學(xué)研究的前沿?zé)狳c(diǎn)。然而,高質(zhì)量大尺寸金剛石膜是戰(zhàn)略產(chǎn)品,在制備技術(shù)和產(chǎn)品受國外壟斷的背景下,本文采用微波等離子體化學(xué)氣相沉積方法,以自主研制的MPCVD裝備為工具,通過優(yōu)化工藝條件,實(shí)現(xiàn)了對金剛石膜純度、晶相結(jié)構(gòu)、生長速率、晶體粒徑、表面質(zhì)量的調(diào)控,并探討了金剛石膜的生長機(jī)制和輔助氣體的協(xié)同作用機(jī)理。采用自主研發(fā)的3 kW/2450MHz型微波等離子體化學(xué)氣相沉積系統(tǒng),以單晶硅(100)為基體材料,分別研究了基體溫度、反應(yīng)腔體壓強(qiáng)和甲烷濃度對金剛石膜純度及生長速率的關(guān)聯(lián)規(guī)律,并采用響應(yīng)曲面優(yōu)化設(shè)計(jì)確定了金剛石膜的最優(yōu)工藝參數(shù)組合:基片溫度為837 ℃,甲烷/氫氣相對濃度為2%,反應(yīng)腔體壓強(qiáng)為6.95kPa,在此條件下金剛石膜的生長速率為0.378 μm/h,金剛石相含量由84.7%提升至89.5%。在獲得CH4/H2體系最優(yōu)制備工藝的基礎(chǔ)上,開展了氧、氬輔助氣體調(diào)節(jié)金剛石膜的生長行為探索。研究了不同氧-氬混合組分構(gòu)成對微米級金剛石膜表面質(zhì)量的協(xié)同調(diào)控規(guī)律,發(fā)現(xiàn)O2:Ar流量組合為1 sccm:14 sccm時(shí),金剛石膜的表面粗糙度最低(約81.5 nm),金剛石相純度為86.1%;同時(shí)研究了 O2流量與超納米級金剛石膜的生長關(guān)聯(lián)規(guī)律,結(jié)果表明:O2流量低于0.5 sccm時(shí),O2促進(jìn)晶粒生長的作用占主導(dǎo)地位;O2流量高于0.5 sccm時(shí),O2促進(jìn)二次形核的作用占主導(dǎo)地位。在獲得CH4/H2傳統(tǒng)原料制備金剛石膜的工藝以后,發(fā)現(xiàn)該原料組合體系存在易燃易爆風(fēng)險(xiǎn),針對該問題本論文開展了無氫氣直接參與的原料體系制備金剛石膜的工藝探索,創(chuàng)新性地采用甲醇-氬氣體系成功制備出金剛石膜。研究表明:金剛石膜以(111)晶面擇優(yōu)生長,金剛石相含量達(dá)75.71%,未發(fā)現(xiàn)石墨相存在。在探明純金剛石膜制備適應(yīng)性工藝的基礎(chǔ)上,開展了硼摻雜金剛石膜的制備工藝研究。采用氧化硼-乙醇溶液為硼源成功制備出的硼摻雜金剛石膜,樣品均呈現(xiàn)(111)晶面擇優(yōu)生長,結(jié)晶度和成膜質(zhì)量良好。少量硼元素有利于提高金剛石膜顆粒的均勻性,當(dāng)氫氣鼓泡流量為3 sccm時(shí),硼摻雜金剛石膜的晶粒一致性最佳,電勢窗口為3.1V,且電化學(xué)可逆性良好。
[Abstract]:Diamond film has excellent physical and chemical properties, such as low coefficient of thermal expansion and friction, wide band gap, excellent wear resistance, high infrared transmittance, good biological compatibility, and good optical, electrical, biological, The preparation technology and functional application of machinery have become a hot research field in material science. However, the high quality and large size diamond film is a strategic product. Under the background that the preparation technology and products are monopolized by foreign countries, the microwave plasma chemical vapor deposition (MPCVD) method is adopted in this paper, and the self-developed MPCVD equipment is used as the tool. By optimizing the process conditions, the growth mechanism of diamond film and the synergistic action mechanism of auxiliary gas were discussed, which can control the purity, crystal phase structure, growth rate, grain size and surface quality of diamond film. The dependence of substrate temperature, pressure of reaction chamber and concentration of methane on the purity and growth rate of diamond film was studied by using a 3 kW / 2450MHz microwave plasma chemical vapor deposition system with single crystal silicon (100) as substrate material. The optimum process parameters of diamond film are determined by the optimum design of response surface. The substrate temperature is 837 鈩，

本文編號：2054739