摘要
利用等离子体增强化学汽相沉积(PECVD),制备了优化的α-Ge:H薄膜,并研究了其结构、光学和电学性质。通过增强氢的稀释,获得了微晶锗(μc-Ge:H)薄膜,其晶化的择优取向是<110>,而热退火使α-Ge:H薄膜晶化的择优取向是<111>。对这两种晶化行为在择优取向上的差异进行了初步的讨论,利用热退火研究α-Ge:H/α-Si:H超晶格薄膜的晶化过程和热稳定性,结果表明超晶格中起薄的锗层和硅层的晶化条件与相应的体材料有很大差别。
Improved α-Ge:H films have been produced by plasma enhanced chemical vapor deposition (PECVD) out of the gas plasma of GeH_4 and H_2. Structural, optical and electronical properties of these films have been investigated. The microcrystalline Ge film (μc-Ge:H) with <110> preferential orientation was deposited by H_2 diluted GeH_4 plasma. On the other hand, the thermal-anneaLing induced crystallization of as-deposited α-Ge:H films revealed <111> preferential orientation A preliminary discussion was proposed to expailan the differences between these two kinds of preferred orientation. The crytallization process and structural stability of α-Ge:H/α-Si:H multilayers have been studied by thermal-annealing. The results obtainted showed that there exists much difference of the crystallization conditions between ultra thin Ge or Si sublayers in α-Ge:H/α-Si:H multilayers and their corresponding bulk materials.
