采用行星热壁式SiC外延炉对100 mm 4°偏轴4H-SiC衬底外延工艺进行了研究。分析了氢气预刻蚀工艺对4°偏轴衬底外延材料表面形貌的影响。采用双指标正交实验,通过极差分析的方法研究了C/Si比、Cl/Si比、主氢流量、生长温度、三...采用行星热壁式SiC外延炉对100 mm 4°偏轴4H-SiC衬底外延工艺进行了研究。分析了氢气预刻蚀工艺对4°偏轴衬底外延材料表面形貌的影响。采用双指标正交实验,通过极差分析的方法研究了C/Si比、Cl/Si比、主氢流量、生长温度、三路气体比等工艺参数对SiC外延厚度和掺杂浓度均匀性指标影响的主次顺序,并给出了优化的外延参数。采用该工艺条件制得的无台阶聚集形貌的SiC外延片片内厚度均匀性和浓度均匀性分别是1.23%和3.32%。展开更多
In order to explore the influence of Cu element on the morphology evolution of the in-situ TiB2 particles, the10 wt.% TiB2 reinforced Al-5 wt.%Cu based composite was prepared by mixed salt casting. The morphology char...In order to explore the influence of Cu element on the morphology evolution of the in-situ TiB2 particles, the10 wt.% TiB2 reinforced Al-5 wt.%Cu based composite was prepared by mixed salt casting. The morphology characterization and transformation of TiB2 reinforcements caused by Cu element were investigated by multi-scale microstructure characterization and statistics techniques. In the case of controlled casting, 5 wt.% Cu addition was found to transform the TiB2 particle morphology from hexagonal plate with sharp edges and corners to hexagonal or tetragonal prism with chamfered edges and corners with the distinguishing growth steps both on the top surface and the side surface. The TiB2 growth in Al-Cu matrix followed the rules: nano-scaled spherical nuclei-polyhedron grains-chamfered hexagonal particles-hexagonal plates-chamfered particles with obvious growth steps. The adsorption energy of Cu on different crystal surfaces of TiB2 was caculated to reveal the influence mechanism and the results indicated that Cu was preferentially adsorbed on the(10-11)TiB2 crystal planes, devoting to the small aspect ratio of TiB2.展开更多
文摘采用行星热壁式SiC外延炉对100 mm 4°偏轴4H-SiC衬底外延工艺进行了研究。分析了氢气预刻蚀工艺对4°偏轴衬底外延材料表面形貌的影响。采用双指标正交实验,通过极差分析的方法研究了C/Si比、Cl/Si比、主氢流量、生长温度、三路气体比等工艺参数对SiC外延厚度和掺杂浓度均匀性指标影响的主次顺序,并给出了优化的外延参数。采用该工艺条件制得的无台阶聚集形貌的SiC外延片片内厚度均匀性和浓度均匀性分别是1.23%和3.32%。
基金Project(2017YFB110400)supported by the National Key Research and Development Program of China。
文摘In order to explore the influence of Cu element on the morphology evolution of the in-situ TiB2 particles, the10 wt.% TiB2 reinforced Al-5 wt.%Cu based composite was prepared by mixed salt casting. The morphology characterization and transformation of TiB2 reinforcements caused by Cu element were investigated by multi-scale microstructure characterization and statistics techniques. In the case of controlled casting, 5 wt.% Cu addition was found to transform the TiB2 particle morphology from hexagonal plate with sharp edges and corners to hexagonal or tetragonal prism with chamfered edges and corners with the distinguishing growth steps both on the top surface and the side surface. The TiB2 growth in Al-Cu matrix followed the rules: nano-scaled spherical nuclei-polyhedron grains-chamfered hexagonal particles-hexagonal plates-chamfered particles with obvious growth steps. The adsorption energy of Cu on different crystal surfaces of TiB2 was caculated to reveal the influence mechanism and the results indicated that Cu was preferentially adsorbed on the(10-11)TiB2 crystal planes, devoting to the small aspect ratio of TiB2.
