摘要
利用水平热壁式CVD外延生长技术,在75mm偏向〈1120〉方向4°的(0001)Si-面n型导电衬底上同质外延生长了4H-SiC薄膜.光学显微镜和原子力显微镜测试结果表明外延层表面存在三角形、胡萝卜状等典型的4°偏轴外延缺陷及普遍的台阶形貌.通过优化外延参数,片内浓度均匀性(σ/mean)和厚度均匀性分别达到4.37%和1.81%.
4H-SiC films were grown on 75mm Si-face n-type substrates 4° off-oriented towards the （1120） direction using a horizontal hot-wall CVD system. Optical and atomic force microscopy results revealed the main defects observed were typical 4° off-large carrots,triangles,and a few down-falls. The most observable feature was the step bunching. By optimizing the process conditions, a low sigma/mean（σ/mean） value of 4.37% and 1.81% in doping concentration and thickness uniformity were obtained on the epitaxy films, respectively.
