Investigation On Growth And Property Of Boron-doped CVD Diamond Films On Quartz

Diamond films have high optical transmittance from the far infrared to theultraviolet light, low refractive index relatively, high thermal conductivity and lowthermal expansion coefficient. It is very suitable for window materials and protectivecoating. In variety of materials, quartz substrate is non-diamond substrate material,which has high transmittance, high insulation and good chemical stability. In thegrowth process without carbide interface layer was formed. So the diamond/quartzstructure with a high transmittance and low electrical conductivity was not affected.Depositing diamond films on quartz as a protective coating and high-performanceelectrode is one of the important applications of diamond films. Preparation andcharacterization of BDD films on quartz substrate research has important significance.In this paper, we used HFCVD and MPCVD equipments to deposited BDD onquartz and discussed the influence of different growth conditions, such as the boronflow, the concentration of methane, the gas pressure and so on. The final result ofexperiments was as follows:HFCVD method was used to deposit boron doped diamond film on quartzsubstrate. A certain amount of boron source (B(OCH3)3) was decomposed. Thedecomposition of oxygen-containing groups or oxygen accelerated etchingnon-diamond phase and promoted the growth of diamond. When the flow of boronwas large, a large number of boron atoms was doped, and affected the growth ofdiamond. The high concentration of methane could improve the diamond nucleationdensity. With the increased of the boron flow, BDD films’resistance decreased. In thevisible region, the optical of transmittance was reach11%. igh quality BDD films’growth conditions was optimized.We have researched the quality and property of BDD film under presence ofboron doping and different methane flow rate by MPCVD method. Boron added to promote the growth of diamond (220) crystal plane and improve the quality of thinfilm. With the increase of methane concentration, diamond grain size graduallydecreased, and the grain size decreased from micrometer to nanometer level. Theoptical transmittance of BDD film was26%. It was large than the film which wasdeposited by HFCVD method.In this paper, by optimizing the experimental parameters of the BDD film growthon quartz, we prepared BDD film which had good electrical conductivity and hightransmittance. Its excellent properties can be used as ideal optical window materials,recyclable and stability can be used as electrode. It provided the experimental datafor the application of BDD films.