等離子體性狀對CVD金剛石沉積結(jié)果影響的研究
發(fā)布時間：2019-05-15 23:19
【摘要】：本文綜述了直流電弧噴射等離子體增強化學(xué)氣相沉積(DC Acjet plasma enhanced CVD)金剛石技術(shù)的發(fā)展歷史和研究現(xiàn)狀,明確提出了等離子體性狀在CVD金剛石過程中是影響沉積物形貌、質(zhì)量和生長速度的重要因素的觀點。 采用大功率直流電弧噴射等離子體沉積設(shè)備,制備了多晶金剛石自支撐膜,包括微米晶、納米晶、超納米晶自支撐膜。利用掃描電鏡、拉曼光譜、X射線衍射儀以及透射電鏡,研究了所制備多晶膜體的形貌、質(zhì)量以及晶體學(xué)性質(zhì),發(fā)現(xiàn)了CVD金剛石膜生長面的一種“菠蘿狀”新形貌,這種形貌是由納米晶構(gòu)成的、各個納米晶粒之間存在著無定形碳,占優(yōu)晶面為(100)晶面,這是金剛石膜體從微米晶向納米晶過渡時的一種中間態(tài)形貌,同時實驗結(jié)果也表明,等離子體的不同部位在襯底上會形成不同的沉積區(qū)。 利用光發(fā)射譜(OES)診斷了直流電弧噴射等離子體的成分,研究了等離子體成分在沉積區(qū)域的空間分布和在沉積時間內(nèi)的濃度演化。實驗結(jié)果顯示不同基元的光發(fā)射存在固定的峰位,雖然強度會隨著反應(yīng)氣體的流量比不同而發(fā)生變化,但是同種基元的譜峰形狀和譜峰位置不變,這表明直流電弧噴射等離子體具有穩(wěn)定的等離子體成分。通過開發(fā)精細OES方法,對近生長表面的等離子體也進行了診斷,結(jié)果發(fā)現(xiàn)：在沉積區(qū)域內(nèi),等離子體中各基元的光發(fā)射強度會隨著空間位置的不同而不同,其中距離沉積面的高度對光發(fā)射強度的影響最大,當距離超過5毫米后,光發(fā)射強度變化不大,但是在近表面5mm以下時,光發(fā)射強度變化顯著。等離子體中的基元光發(fā)射強度隨時間的延長會發(fā)生波動,當沉積時間小于30小時,C2與CH光發(fā)射強度的比值近似等于2.08,超過30小時,C2與CH光發(fā)射強度的比值會單調(diào)增加。 利用計算機模擬分析技術(shù)模擬了不同參數(shù)下的等離子體流動特性,包括流場、溫度場、壓力場。模擬結(jié)果顯示,在襯底近表面的等離子體可以分為兩個區(qū)域,一個是滯止區(qū),一個是沿壁射流區(qū)。在射流距離一定時,隨著射流速度加大,滯止區(qū)變小,同時沿壁射流區(qū)的邊界層厚度也減小；在射流速度一定時,隨著射流距離的增大,滯止區(qū)變大,沿壁射流區(qū)的邊界層變厚。當射流速度一定時,溫度場隨著射流距離變大而變得不均勻,當射流距離一定時,溫度場又會隨射流速度變大而變得均勻。滯止區(qū)壓力最大,在沿壁射流區(qū)壓力會隨著距離的變長而減小。 研究了直流電弧技術(shù)在高CH4/H2條件下的同質(zhì)形核孕育期。利用FIB、 TEM、HREM、EELS等離線技術(shù)分析了在多晶金剛石上進行金剛石早期沉積的情況,發(fā)現(xiàn)金剛石形核之前存在一個非晶碳層,隨后金剛石的晶核在這層非晶碳中形成,形成的晶核尺寸在2-3nm左右。根據(jù)模擬計算結(jié)果,設(shè)定了精細OES的測量點,結(jié)果表明在大碳氫比條件下的金剛石沉積早期,邊界層中的C2基元的光發(fā)射強度會發(fā)生變化,在一定時間中會有明顯的波動現(xiàn)象。結(jié)合離線技術(shù)的檢測結(jié)果,可以判明這些波動與金剛石的形核有關(guān)。根據(jù)OES的結(jié)果可以推斷,在大的FCH4/FH2條件下(15%),CVD金剛石的形核孕育期在6-8分鐘,且隨著FCH4/FH2增大,孕育期縮短。OES的結(jié)果同時也表明,在金剛石襯底上的形核是爆發(fā)式的形核。 在天然金剛石的(100)面上采用“定態(tài)”和“動態(tài)”兩種生長模式制備了毫米級單晶金剛石顆粒,其中“定態(tài)”生長模式工藝簡單,但是籽晶的裝夾方式是保證生長能否繼續(xù)的關(guān)鍵因素�！皠討B(tài)”生長模式可以通過改變襯底沉降速度來操控生長速度,單晶的生長速度隨著襯底沉降速度的增加而增加,但是過快的襯底沉降速度會導(dǎo)致由應(yīng)力誘導(dǎo)的ATG型形貌,進而引發(fā)多晶生長。在“動態(tài)”生長模式中,單晶的生長速度可以達到52μm/h。
[Abstract]:In this paper, the development history and research status of DC-arc plasma enhanced chemical vapor deposition (DC Acjet plasma enhanced CVD) diamond technology are reviewed, and the effects of plasma character on the morphology of the deposit in the process of CVD diamond are put forward. An important factor in the quality and speed of growth. the polycrystalline diamond self-supporting film is prepared by adopting a high-power direct current arc spraying plasma deposition equipment, The morphology, quality and crystallography of the prepared polycrystalline film were studied by means of scanning electron microscope, Raman spectrum, X-ray diffractometer and transmission electron microscope. And the experimental results also show that different parts of the plasma form different deposition on the substrate. In this paper, the spatial distribution of the plasma components in the deposition area and the concentration of the plasma in the deposition time are studied by using the light emission spectrum (OES) to diagnose the components of the DC arc spray plasma. The experimental results show that the light emission of different elements has a fixed peak, although the intensity changes with the flow rate of the reaction gas, the spectral peak shape and the spectral peak position of the same cell do not change, which indicates that the DC arc spray plasma has a stable plasma. By developing the fine OES method, the plasma of the near-growing surface is also diagnosed. The results show that in the deposition area, the light emission intensity of the elements in the plasma varies with the spatial position, and the height of the distance deposition surface is the shadow of the light emission intensity. In response to the maximum, when the distance exceeds 5 mm, the intensity of the light emission is not large, but when the near surface is less than 5 mm, the light emission intensity changes And the ratio of C2 to CH light emission intensity is approximately equal to 2.08 when the deposition time is less than 30 hours, and the ratio of the C2 to the CH light emission intensity is single. The characteristics of plasma flow under different parameters are simulated by computer simulation and analysis, including flow field, temperature, The simulation results show that the plasma in the near surface of the substrate can be divided into two areas, one is the stagnation zone, one is along the wall-jet area, as the jet velocity increases, the stagnation area becomes smaller, and the thickness of the boundary layer along the wall-jet area is also reduced; at the same time, as the jet velocity is constant, the stagnation-stopping area is larger with the increase of the distance of the jet, and along the wall-jet area, The boundary layer is thickened. When the velocity of the jet is constant, the temperature field becomes non-uniform with the distance of the jet, and when the distance of the jet is constant, the temperature field will increase with the velocity of the jet. And the pressure of the stagnation zone is the largest, and the pressure in the jet zone along the wall will follow the distance. The effect of direct current arc in the condition of high CH4/ H2 is studied. The early deposition of the diamond on the polycrystalline diamond was analyzed by using an off-line technique such as FIB, TEM, HREM, and EELS. It was found that there was an amorphous carbon layer before the nucleation of the diamond, and then the crystal nucleus of the diamond was formed in the amorphous carbon, and the crystal nucleus was formed. The measurement points of fine OES are set according to the results of the simulation. The results show that in the early stage of diamond deposition under the condition of large hydrocarbon ratio, the light emission intensity of the C2 elements in the boundary layer will change, and there will be some time. Obviously, the fluctuation and gold can be determined by combining the detection results of off-line technology. Based on the results of the OES, it is concluded that the nucleation and incubation period of CVD diamond is 6-8 minutes under the condition of large FCH4/ FH2 (15%), and with the increase of FCH4/ FH2 The results of OES also show that nucleation on the diamond substrate The surface of the natural diamond (100) adopts two growth modes of "fixed state" and "dynamic" to prepare the millimeter-grade single crystal diamond particles, wherein the "fixed state" growth mode is simple in process, but the clamping mode of the seed crystal is to ensure the growth The dynamic "growth mode can control the growth rate by changing the settling velocity of the substrate, and the growth speed of the single crystal is increased with the increase of the settling speed of the substrate, but too fast the settling speed of the substrate can lead to the ATG-type morphology induced by the stress. in a "dynamic" growth mode, that growth rate of the single crystal may
【學(xué)位授予單位】：北京科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：TQ163
本文編號：2477842
[Abstract]:In this paper, the development history and research status of DC-arc plasma enhanced chemical vapor deposition (DC Acjet plasma enhanced CVD) diamond technology are reviewed, and the effects of plasma character on the morphology of the deposit in the process of CVD diamond are put forward. An important factor in the quality and speed of growth. the polycrystalline diamond self-supporting film is prepared by adopting a high-power direct current arc spraying plasma deposition equipment, The morphology, quality and crystallography of the prepared polycrystalline film were studied by means of scanning electron microscope, Raman spectrum, X-ray diffractometer and transmission electron microscope. And the experimental results also show that different parts of the plasma form different deposition on the substrate. In this paper, the spatial distribution of the plasma components in the deposition area and the concentration of the plasma in the deposition time are studied by using the light emission spectrum (OES) to diagnose the components of the DC arc spray plasma. The experimental results show that the light emission of different elements has a fixed peak, although the intensity changes with the flow rate of the reaction gas, the spectral peak shape and the spectral peak position of the same cell do not change, which indicates that the DC arc spray plasma has a stable plasma. By developing the fine OES method, the plasma of the near-growing surface is also diagnosed. The results show that in the deposition area, the light emission intensity of the elements in the plasma varies with the spatial position, and the height of the distance deposition surface is the shadow of the light emission intensity. In response to the maximum, when the distance exceeds 5 mm, the intensity of the light emission is not large, but when the near surface is less than 5 mm, the light emission intensity changes And the ratio of C2 to CH light emission intensity is approximately equal to 2.08 when the deposition time is less than 30 hours, and the ratio of the C2 to the CH light emission intensity is single. The characteristics of plasma flow under different parameters are simulated by computer simulation and analysis, including flow field, temperature, The simulation results show that the plasma in the near surface of the substrate can be divided into two areas, one is the stagnation zone, one is along the wall-jet area, as the jet velocity increases, the stagnation area becomes smaller, and the thickness of the boundary layer along the wall-jet area is also reduced; at the same time, as the jet velocity is constant, the stagnation-stopping area is larger with the increase of the distance of the jet, and along the wall-jet area, The boundary layer is thickened. When the velocity of the jet is constant, the temperature field becomes non-uniform with the distance of the jet, and when the distance of the jet is constant, the temperature field will increase with the velocity of the jet. And the pressure of the stagnation zone is the largest, and the pressure in the jet zone along the wall will follow the distance. The effect of direct current arc in the condition of high CH4/ H2 is studied. The early deposition of the diamond on the polycrystalline diamond was analyzed by using an off-line technique such as FIB, TEM, HREM, and EELS. It was found that there was an amorphous carbon layer before the nucleation of the diamond, and then the crystal nucleus of the diamond was formed in the amorphous carbon, and the crystal nucleus was formed. The measurement points of fine OES are set according to the results of the simulation. The results show that in the early stage of diamond deposition under the condition of large hydrocarbon ratio, the light emission intensity of the C2 elements in the boundary layer will change, and there will be some time. Obviously, the fluctuation and gold can be determined by combining the detection results of off-line technology. Based on the results of the OES, it is concluded that the nucleation and incubation period of CVD diamond is 6-8 minutes under the condition of large FCH4/ FH2 (15%), and with the increase of FCH4/ FH2 The results of OES also show that nucleation on the diamond substrate The surface of the natural diamond (100) adopts two growth modes of "fixed state" and "dynamic" to prepare the millimeter-grade single crystal diamond particles, wherein the "fixed state" growth mode is simple in process, but the clamping mode of the seed crystal is to ensure the growth The dynamic "growth mode can control the growth rate by changing the settling velocity of the substrate, and the growth speed of the single crystal is increased with the increase of the settling speed of the substrate, but too fast the settling speed of the substrate can lead to the ATG-type morphology induced by the stress. in a "dynamic" growth mode, that growth rate of the single crystal may
【學(xué)位授予單位】：北京科技大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2015
【分類號】：TQ163
【參考文獻】
相關(guān)期刊論文 前10條
1 陳旭宏,趙立合,呂反修;直流等離子體噴射鍍膜設(shè)備的傳熱數(shù)學(xué)模型[J];北京科技大學(xué)學(xué)報;1999年01期
2 鐘國仿,申發(fā)振,唐偉忠,呂反修;基片溫度對直流電弧等離子體噴射沉積金剛石膜的影響[J];北京科技大學(xué)學(xué)報;1999年04期
3 黃天斌,唐偉忠,呂反修,張維敬;大面積金剛石膜生長環(huán)境氣氛的計算機模擬[J];北京科技大學(xué)學(xué)報;2000年02期
4 安希忠,張禹,劉國權(quán),秦湘閣,王輔忠,劉勝新;CVD金剛石膜｛100｝取向生長的原子尺度仿真[J];北京科技大學(xué)學(xué)報;2002年02期
5 呂反修;;大面積光學(xué)級金剛石自支撐膜制備、性能及其在高技術(shù)領(lǐng)域應(yīng)用前景[J];中國表面工程;2010年03期
6 王傳新,汪建華,馬志斌,滿衛(wèi)東,王升高,康志成,吳素娟;低偏壓下化學(xué)氣相沉積金剛石薄膜的生長形貌研究[J];材料保護;2003年05期
7 黃建良;汪建華;;CVD金剛石薄膜的形核研究[J];材料導(dǎo)報;2007年S2期
8 王兵,梅軍,李力,季錫林,冉均國,茍立;CVD金剛石膜產(chǎn)業(yè)化制備技術(shù)研究[J];材料科學(xué)與工藝;2003年01期
9 黃元盛,劉正義,邱萬奇;CVD金剛石薄膜二次形核機制的研究[J];材料科學(xué)與工程;2001年01期
10 唐壁玉,靳九成,陳宗璋;CVD金剛石成核的最新研究[J];材料開發(fā)與應(yīng)用;1998年06期
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