Influences of annealing on structural and compositional properties of Al_2O_3 thin films grown on 4H–SiC by atomic layer deposition

作     者：田丽欣 张峰 申占伟 闫果果 刘兴昉 赵万顺 王雷 孙国胜 曾一平 

作者机构：Key Laboratory of Semiconductor Material SciencesBeijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of Sciences 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2016年第25卷第12期

页      面：468-473页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

基　　金：Project supported by the National Basic Research Program of China(Grant No.2015CB759600) the National Natural Science Foundation of China(Grant Nos.61474113,61574140,and 61274007) the Beijing Nova Program,China(Grant No.xx2016071) the CAEP Microsystem and THz Science and Technology Foundation(Grant No.CAEPMT201502) 

主　　题：atomic layer deposition annealing transition 4H-SiC 

摘      要：Annealing effects on structural and compositional performances of A1203 thin films on 4H-SiC substrates are studied comprehensively. The Al2O3 films are grown by atomic layer deposition through using trimethylaluminum and H2O as precursors at 300 ℃, and annealed at various temperatures in ambient N2 for 1 min. The Al2O3 film transits from amorphous phase to crystalline phase as annealing temperature increases from 750 ℃ to 768 ℃. The refractive index increases with annealing temperature rising, which indicates that densification occurs during annealing. The densification and grain formation of the film upon annealing are due to crystallization which is relative with second-nearest-neighbor coordination variation according to the x-ray photoelectron spectroscopy （XPS）. Although the binding energies of Al 2p and O ls increase together during crystallization, separations between Al 2p and O ls are identical between as-deposited and annealed sample, which suggests that the nearest-neighbour coordination is similar.