| The unique regular tetrahedron structure of diamond makes it have excellent physical and chemical properties.The high-quality diamond film can be used for tool coating,optical window,acoustic diaphragm,semiconductor materials and so on.Since natural diamond reserves are scarce and expensive,the research work of diamond film has become a hot spot in recent years.By chemical vapor deposition?Chemical Vapor Deposition,CVD?method,a diamond film with properties comparable to that of natural diamond can be prepared.Therefore,most high-quality diamond films are prepared by this method.Among them,the microwave plasma chemical vapor deposition?Microwave plasma CVD,MPCVD?method does not have the pollution of the discharge electrode during the deposition of the diamond film,and the controllability is good.The diamond film obtained by this method gets the highest quality,so the MPCVD method is recognized as a high The preferred method of quality diamond film.This paper first discusses the diamond film and diamond film deposition equipment at home and abroad.By analyzing existing diamond film deposition equipment,the necessary conditions for high power deposition of diamond film are summarized.Combining the focusing characteristics of the ellipsoidal resonator cavity and the model of the MPCVD device with a loop coupling antenna type with high power deposition characteristics,a new type of arc surface adjustment high power MPCVD deposition device was designed.The device has high power and field focusing Strong ability,strong vacuum tightness,double adjustment mechanism and advantages of full water cooling structure design.The size of the device was optimized by numerical simulation,and the resonant cavity model with the optimal size was achieved.Secondly,this paper analyzes the factors that may cause device detuning,and when the device is detained?microwave frequency deviation,actual device size error,substrate height change?,it is tuned with an adjustable arc surface adjustment body Simulation research.Studies have shown that the frequency deviation range is greater than±10MHz has a great impact on the device,the adjustment device can be tuned within the range of±30MHz;when there is a+1mm error in the cavity diameter under the resonant cavity,you can adjust the body by adjusting the 2mm arc surface,when the error is 1mm,it can be adjusted by increasing the 2mm arc surface adjustment body;when the substrate height is increased by 2mm,the arc surface adjustment body can be adjusted down by 5mm,and the base adjustment body can be adjusted down by 3mm,which can make the electric field strength reach the highest value,which proves the adjustment of the device The controllability of the function on the electric field strength and the degree of aggregation.By building a 10KW arc surface adjustment high power MPCVD device platform,the performance of the device to maintain a vacuum was first tested,and the measured leak rate was 3.6×10-6Pa·m3·s-1.Then,the device was utilized to conduct diamond film deposition experiments on monocrystalline silicon and monocrystalline diamond substrate.Using a scanning electron microscope,it can be observed that the diamond film prepared on the single crystal silicon substrate has good crystallinity,obvious grain boundaries,and the size of the crystal grain is basically uniform and square,with an average crystal grain size of2?m-5?m.There is no obvious secondary nucleation phenomenon;On the single crystal diamond seed crystal growth of diamond film before using O2/H2 plasma etching in advance can ensure the growth of the growth of single crystal diamond surface contains less defects,the preparation of diamond film has excellent quality,design a new type of curve to adjust power MPCVD device with excellent sedimentary properties,for further research and application of high quality diamond film provides a good platform. |
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