大面积无衬底自支撑金刚石厚膜沉积

Preparation of Large Area Free Standing Thick Diamond Wafers

讨论了在采用直流电弧等离子体喷射CVD工艺沉积大面积无衬底自支撑金刚石厚膜时遇到的若干技术问题．在制备过程中经常出现的膜炸裂现象，主要是由于膜和衬底材料线膨胀系数差异引起的巨大热应力，而衬底表面状态的控制、沉积过程中工艺参数的优化和控制也是一个重要的因素．因此，必须对整个金刚石厚膜沉积过程进行严格而系统的控制，才能有效地保证获得无裂纹大面积金刚石自支撑厚膜．

Technical problems encounered in the preparation of large area free standing thick diamond films are discussed. Cracking of deposited diamond wafers is mainly due to the huge thermal stress resulted from the big difference in linear expansion coefficients between diamond and the Mo substrae. While the status of the surface preparation of the substrate, the control and optimization of process parameters are also very important. In order to obtain crack free large area thick diamond wafers it is necessary to strictly control the every step of the whole deposition process.