【摘要】：高品質(zhì)金剛石膜材料在現(xiàn)代技術(shù)的各個(gè)領(lǐng)域中都有著重要的應(yīng)用前景。而作為高品質(zhì)金剛石膜首選的制備方法,微波等離子體化學(xué)氣相沉積(MPCVD)技術(shù)近年來已逐漸走向成熟。但是,相比于美、歐、日等國,我國在高品質(zhì)金剛石膜的MPCVD制備裝備、制備技術(shù)方面一直處于落后狀態(tài),嚴(yán)重制約了高品質(zhì)金剛石膜在我國眾多高技術(shù)領(lǐng)域中的應(yīng)用。為推動(dòng)我國MPCVD金剛石膜沉積技術(shù)的發(fā)展和高品質(zhì)金剛石膜在各領(lǐng)域中的應(yīng)用,本文以高功率MPCVD金剛石膜沉積裝置的研制入手,繼而開展了高功率下高品質(zhì)金剛石膜制備工藝以及金剛石膜微波介電性能與其質(zhì)量相互關(guān)系的研究。 通過對(duì)MPCVD金剛石膜沉積裝置諧振腔內(nèi)等離子體分布、電磁場(chǎng)分布和氣體溫度分布的數(shù)值模擬,本文提出了一種新型穹頂式MPCVD金剛石膜沉積裝置。該裝置具有以下的優(yōu)點(diǎn)：(1)石英微波窗口距離等離子體較遠(yuǎn),可避免高功率下被等離子體刻蝕的危險(xiǎn)；(2)擁有雙調(diào)諧機(jī)制,可以方便有效地實(shí)現(xiàn)等離子體分布狀態(tài)的調(diào)節(jié)；(3)擁有極佳的真空性能,靜態(tài)升壓法的測(cè)試顯示,裝置的真空泄漏率僅為3.7×10-6Pa·m3·s-1左右；(4)擁有優(yōu)異的水冷設(shè)計(jì)系統(tǒng)。實(shí)驗(yàn)表明,綜合了以上優(yōu)異性能的新型穹頂式MPCVD裝置適合于高微波輸入功率下高品質(zhì)金剛石膜的制備。 在新型穹頂式MPCVD裝置成功建立的基礎(chǔ)上,本文開展了高品質(zhì)金剛石膜最優(yōu)制備工藝的探索,研究了包括沉積溫度、甲烷濃度和氣體流量三個(gè)重要的工藝參數(shù)對(duì)金剛石膜表面形貌、沉積速率、品質(zhì)以及取向變化的影響,并研究了裝置的真空泄漏率對(duì)于高品質(zhì)金剛石膜制備的影響。研究結(jié)果表明,對(duì)于新型穹頂式MPCVD裝置而言,當(dāng)沉積溫度處于1030℃附近,甲烷濃度處于3.5%附近,氣體流量大于100sccm時(shí),最有利于高品質(zhì)金剛石膜的制備；裝置的真空性能會(huì)極大地改變金剛石膜的品質(zhì),即良好的真空密封性能是MPCVD裝置制備高品質(zhì)金剛石膜的關(guān)鍵之一。但另一方面,裝置真空密封性能的改善卻會(huì)顯著降低金剛石膜的沉積速率。 使用新型穹頂式MPCVD裝置,在優(yōu)化的工藝條件下,實(shí)現(xiàn)了9.2kW高功率下高品質(zhì)金剛石自支撐膜的成功制備。檢測(cè)結(jié)果顯示,高品質(zhì)金剛石膜呈現(xiàn)為無色透明狀態(tài),光學(xué)吸收邊約為223nm,其Raman譜金剛石特征峰的半高寬為2.0cm-1,氮雜質(zhì)含量不足1ppm,在6.5-251μm的紅外波段內(nèi)光學(xué)透過率大于70%。這表明,本文制備的金剛石自支撐膜擁有著極高的品質(zhì),同時(shí)也充分顯示了新型穹頂式MPCVD裝置在高功率下長時(shí)間運(yùn)行制備高品質(zhì)金剛石膜的能力。 最后,本文建立了一種分體圓柱諧振腔式低損耗薄膜介電性能測(cè)試裝置,并對(duì)不同質(zhì)量、不同方法制備的金剛石膜在Ka波段內(nèi)進(jìn)行了微波介電性能測(cè)試。研究表明,四個(gè)金剛石膜(1#、2#、3#和4#的Raman譜半高寬值依次增大,對(duì)應(yīng)的金剛石膜品質(zhì)依次惡化。隨著四個(gè)金剛石膜品質(zhì)的降低,它們的介電常數(shù)值依次增大,但其微波介電損耗角正切值卻呈現(xiàn)出2#、3#和4#三個(gè)樣品依次增大,而使用其他分析手段證明的品質(zhì)較好的1存樣品的介電損耗角正切值略高于2#樣品的情況。研究表明,1#樣品的微波介電損耗角正切值略高于2#樣品的原因可能與1#樣品的表面存在孔洞和內(nèi)部存在黑色組織缺陷有關(guān)。上述測(cè)試結(jié)果一方面證明了MPCVD方法制備的金剛石膜可具有較低的介電損耗,同時(shí)也證明了金剛石膜的介電損耗與其微觀結(jié)構(gòu)密切相關(guān)。在今后的研究中,應(yīng)該對(duì)黑色孔洞型缺陷的形成機(jī)理、影響因素以及屋頂型孿晶組織對(duì)該類缺陷及金剛石膜介電性能的影響展開進(jìn)一步的系統(tǒng)研究。
[Abstract]:The high-quality diamond film material has an important application prospect in all fields of modern technology. The microwave plasma chemical vapor deposition (MPCVD) technology has gradually become mature in recent years as the first choice for high quality diamond films. However, compared with America, Europe, Japan and other countries, China has been in a backward state in the preparation of MPCVD of high quality diamond film, and has seriously restricted the application of high-quality diamond film in many high-tech fields in China. In order to promote the development of MPCVD diamond film deposition technology in China and the application of high quality diamond film in all fields, this paper starts with the development of high power MPCVD diamond film deposition device. in turn, that preparation technology of high-quality diamond film at high power and the relationship between the microwave dielectric property and the quality of the diamond film are studied. Based on the numerical simulation of the plasma distribution, the electromagnetic field distribution and the gas temperature distribution in the resonant cavity of the MPCVD diamond film deposition apparatus, a new type of top-top type MPCVD diamond film deposition is proposed in this paper. The device has the following advantages: (1) the quartz microwave window is far from the plasma and can avoid the danger of being etched by the plasma at high power; and (2) the device has a double-tuning mechanism, so that the plasma distribution state can be conveniently and effectively realized. and (3) with excellent vacuum performance, the static step-up method shows that the vacuum leakage rate of the device is only about 3. 7-10-6Pa 路 m3 路 s-1; and (4) it has excellent water-cooling design. The experimental results show that the novel top-top type MPCVD device with the above excellent properties is suitable for high-quality diamond films with high microwave input power On the basis of the successful establishment of the new type top-top MPCVD device, the paper studies the optimum preparation technology of high-quality diamond film, and studies the surface morphology of the diamond film by three important process parameters including the deposition temperature, the methane concentration and the gas flow rate. The influence of the deposition rate, the quality and the orientation change is studied, and the vacuum leakage rate of the device is studied for high quality diamond film The results show that, for a new type of top-top MPCVD device, when the deposition temperature is in the vicinity of 1030 鈩，

本文編號(hào)：2326000