Photoionization Spectrum Measurement and Analysis of Deep Level in GaN Epilayers
WANG Ying1, LI Su-yun1,2，YIN Zhi-jun3
1. School of Electronic Science and Technology, Anhui University, Hefei 230039, China 2. Modern Educational Technology Center, Anhui University, Hefei 230039, China 3. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Heifei 230031, China
Abstract：Photoionization spectrum measurement method was designed based on constant photocurrent control by PID technology. Combined with photocurrent and hall effect measurements, this method can provide exact photoionization cross section in GaN epilayers. The measurement results of GaN epilayers show that, the responsiveness of photoelectric detector is the dominating factor affecting test accuracy. The test error increases with the incident photon energy. An 8% test error can be produced under incident photon with 3.2 eV photon energy. Deep level trap in GaN epilayers can still absorb photons with incident energy less than the energy difference between deep level trap and conductor band(2.85 eV), which implies that the lattice relaxation associated with deep level trap takes places in GaN epilayers.
王 莹1，李素云1, 2，尹志军3 . 氮化镓材料中深能级中心光离化谱测试与分析 [J]. 光谱学与光谱分析, 2010, 30(08): 2219-2222.
WANG Ying1, LI Su-yun1,2，YIN Zhi-jun3 . Photoionization Spectrum Measurement and Analysis of Deep Level in GaN Epilayers . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2010, 30(08): 2219-2222.
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