基于Cr过渡层沉积CVD金刚石涂层的试验研究

Deposition of CVD Diamond Thin Film on Carbide Substrate by Using Cr Interlayer

研究了在硬质合金上基于 Cr过渡层沉积 CVD( Chemical vapor deposition)金刚石涂层的工艺 ,利用自制的 CVD金刚石沉积设备制备出晶形完整、晶粒大小均匀、分布连续的金刚石涂层。用 SEM和 Raman光谱对CVD金刚石涂层进行了分析。结果表明 ,沉积工艺对金刚石的形态和成分有显著影响 ,基体温度在 80 0℃左右时 ,可以得到晶形完整 ,非金刚石成分较少 ,与基体结合紧密的 CVD金刚石涂层。

The process of hot filament chemical vapor deposition (HFCVD) of diamond thin film on the chrome interlayer electro-deposited on the cemented carbide is discussed. A hot filament temperature in the range of 2 400~2 500℃; a substrate temperature in the range of 700~850℃; a CH_4concentration of 1%~2%; a H_2flow rate of 400 SCCM; and a chamber pressure in the range of 3～5 kPa are identified as the optimum deposition conditions for producing high quality diamond coatings. The diamond thin film with regular and uniformly distributed crystal is obtained by the HFCVD equipment. The surface of the CVD diamond thin film is studied by scanning electron microscope (SEM) and Raman scattering spectroscopy (Raman). Experimental results show that the process parameter has a great influence on the micro-structure and composition of the diamond thin film. A good quality diamond thin film with good micro-structure and little non-diamond composition can be obtained when the substrate temperature is heated about 800℃. High internal stress is also found in the diamond thin film.