环形天线-椭球谐振腔式MPCVD装置高功率下沉积高品质金刚石膜

Deposition of High Quality Diamond Films with High Power by a Circumferential Antenna Ellipsoidal Cavity Type MPCVD Reactor

介绍了自行研制的环形天线-椭球谐振腔式高功率MPCVD装置的结构特点,展示并研究了新装置在高功率条件下的放电特性。在10.5 k W的高微波输入功率下成功制备了直径50 mm,厚度接近1 mm的高品质自支撑金刚石膜。在真空泄漏速率约2.5×10^(-6)Pa·m^3/s的条件下金刚石膜的生长速率达到6μm/h,金刚石膜厚度偏差小于±2.1%。抛光后的金刚石膜红外透过率在6.5~25μm范围内接近71%;紫外透过率在270 nm处超过50%,金刚石膜样品的光学吸收边约为225 nm;通过紫外吸收光谱计算的金刚石膜样品中的氮杂质含量约为1.5 ppm;金刚石膜的拉曼半峰宽小于1.8 cm^(-1)。

The structural features of a home-made circumferential antenna ellipsoidal cavity type MPCVD reactor was recommended. The discharge characteristics under high power levels was demonstrated and discussed. High quality diamond film with diameter of 50 mm and thickness of about 1 mm was synthesized under 10. 5 kW input microwave power. The growth rate of the diamond film is about 6 μm/ h with the leak rate of about 2.5 × 10^-6 Pa · m^3/ s for the reactor and the deviation of the thickness is less than ±2. 1%. Test results show that the polished diamond film possessed excellent characteristics such as FWHM of Raman peak of only 1.8 cm^-1, a cutoff wavelength of 225 nm, UV transmittance at 270 nm is more than 50% , a nitrogen content about 1. 5 ppm and transmission near 71% in the 6. 5-25μm range.