半导体光电, 2012, 33 (3): 367, 网络出版: 2012-06-25
生长压力对GaN材料光学与电学性能的影响
Influence of Growth Pressure on the Optical and Electrical Properties of GaN Films
生长压力 光致发光 载流子浓度 载流子迁移率 GaN GaN MOCVD MOCVD growth pressure photoluminescence carrier concentration carrier mobility
摘要
研究了采用MOCVD技术分别在100与500Torr反应室压力下生长的非故意掺杂GaN薄膜的光学与电学性能。研究表明,低压100Torr外延生长条件可以有效地降低Ga与NH3气相反应造成GaN薄膜的碳杂质沾污,从而抑制造成光致发光中黄光峰与蓝光峰的深受主的形成,所制备的材料表现出较好的光学性能。同时,不同生长压力下的GaN薄膜表现出相异的电学性能,即在500Torr下生长的样品通常表现出更高的载流子浓度((4.6~6.4)×1016cm-3)与更高的迁移率(446~561cm2/(V·s)),而100Torr下生长的样品通常表现为更低的载流子浓度(1.56~3.99)×1016cm-3与更低迁移率(22.9~202cm2/(V·s))。
Abstract
The optical and electrical properties of unintentionally doped GaN films grown at 100Torr and 500Torr pressure respectively by MOCVD system were investigated. It is proved that low growth pressure of 100Torr can effectively reduce the Carbon impurities in the GaN films to suppress the formation of deep acceptors which are the origin of yellow and blue light peaks in the photoluminescence measurement, and the GaN films fabricated under such conditions present better optical properties. Meantime, GaN films grown at different pressure show different electrical properties. The GaN films grown at 500Torr usually have higher carrier concentration ((4.6~6.4)×1016cm-3) and higher carrier mobility (446~561cm2/(V·s)), while the GaN films grown at 100Torr usually have lower carrier concentration ((1.56~3.99)×1016cm-3) and lower carrier mobility(22.9~202cm2/(V·s)).
冯雷, 韩军, 邢艳辉, 范亚明. 生长压力对GaN材料光学与电学性能的影响[J]. 半导体光电, 2012, 33(3): 367. FENG Lei, HAN Jun, XING Yanhui, FAN Yaming. Influence of Growth Pressure on the Optical and Electrical Properties of GaN Films[J]. Semiconductor Optoelectronics, 2012, 33(3): 367.