SiC衬底上β-Ga_(2)O_(3)薄膜生长及p-SiC/n-β-Ga_(2)O_(3)异质结光伏特性  

β-Ga_(2)O_(3) Films Growth on SiC Substrate and p-SiC/n-β-Ga_(2)O_(3) Heterojunction Photovoltaic Properties

作　　者：罗建仁 王相虎 樊天曜 金嘉妮 张如林 LUO Jianren;WANG Xianghu;FAN Tianyao;JIN Jiani;ZHANG Rulin(School of Materials, Shanghai Dianji University, Shanghai 201306, China)

机构地区：[1]上海电机学院材料学院,上海201306

出　　处：《人工晶体学报》2021年第12期2219-2224,共6页Journal of Synthetic Crystals

基　　金：国家自然科学基金(10804071,51671125);上海市自然科学基金(19ZR1420100);认知无线电与信息处理省部共建教育部重点实验室(桂林电子科技大学)开放课题(CRKL180205)。

摘　　要：本文采用脉冲激光沉积(PLD)技术在p型4H-SiC衬底上,制备出沿(403)择优生长的β-Ga_(2)O_(3)薄膜。结果表明,衬底生长温度对β-Ga_(2)O_(3)薄膜的形貌、结构、组分,以及生长机理都有重要影响。当生长温度由300℃升高至500℃时,薄膜结晶质量随生长温度升高而提高,当温度进一步升高到600℃时,薄膜结晶质量变差,这是由于在相对低温(500℃以下)阶段,生长温度越高,沉积在衬底上原子的动能越大,越容易迁移,使得β-Ga_(2)O_(3)薄膜主要按照二维生长模式进行生长,薄膜结晶质量提高,表现为随着生长温度升高,粗糙度降低。但当温度上升到600℃时,由于4H-SiC衬底和β-Ga_(2)O_(3)薄膜之间的热膨胀系数存在差异,导致薄膜生长由主要以二维生长模式向三维岛状演变。基于p-4H-SiC/n-β-Ga_(2)O_(3)构筑的异质结太阳电池,其标准测试条件下光电转换效率达到3.43%。In this paper,β-Ga_(2)O_(3) films grown preferentially along(403)were prepared on p-type 4H-SiC substrate by pulsed laser deposition(PLD).The results show that the growth temperature has an important influence on the morphology,structure,composition and growth mechanism ofβ-Ga_(2)O_(3) film.When the growth temperature increases from 300℃to 500℃,the crystalline quality of theβ-Ga_(2)O_(3) film raises with the increasing temperature,but when the temperature further increases to 600℃,the crystalline quality of the thin film becomes worse.It was tried to explain that the kinetic energy of atoms deposited on the substrate increases with the increase of growth temperature below 500℃,leading to easier migration of atoms,finally,the film is grown in two-dimensional mode and has smaller roughness as measured by AFM.However,when the temperature further increases to 600℃,the two-dimensional growth mode is changed to three-dimensional island shape,because of the difference in thermal expansion coefficient between 4H-SiC substrate andβ-Ga_(2)O_(3) thin film,resulted in the larger roughness.The photovoltaic conversion efficiency of heterojunction solar cell based on p-4H-SiC/n-β-Ga_(2)O_(3) reaches 3.43%under standard test conditions.

关 键 词：β-Ga_(2)O_(3) 4H-SiC衬底 脉冲激光沉积 生长温度 异质结太阳能电池 光电转换效率 

分 类 号：TM914.4[电气工程—电力电子与电力传动]