GaInP材料生长及其性质研究

THE PROPERTIES OF GaInP GROWN BY MOCVD

用常压ＭＯＣＶＤ在半绝缘ＧａＡｓ衬底上生长了Ｇａ＿ｘＩｎ＿（１－ｘ）Ｐ（ｘ＝０．４７６～０．５２）外延层，对外延层进行了Ｘ光双晶衍射、Ｈａｌｌ和光致发光（ＰＬ）测试。７７Ｋ下电子迁移率达３３００ｃｍ￣２／Ｖ．ｓ（浓度为１．４×１０￣（１６）ｃｍ￣（－３））。载流子浓度随生长温度升高，随Ⅴ／Ⅲ比的增大而降低，并提出Ｐ空位（Ｖｐ）是自由载流子的一个重要来源，１７ＫＰＬ谱中，Ｇａ＿（０．５）Ｉｎ＿（０．５）Ｐ（Ｔｇ＝６５０℃，Ⅴ／Ⅲ＝７０）的峰能为１．８２８ｅＶ，半峰宽为１９ｍｅＶ。另外，在１．８４９ｅＶ处还有一较弱的峰，ＧａＩｎＰ峰能和其计算的带隙最大相差１１３ｍｅＶ，这可能与ＧａＩｎＰ中杂质或缺陷以及其中存在有序结构有关。

Ga_xIn_(1-x)P ( x = 0. 4 7 6 ～ 0 . 5 2 ) epitaxial layers were grown on 5°off (100) GaAs substratesiowards < 1 1 0 > by atmospheric Metalorganic Chemical Vapor Deposition (MOCVD) equipment,They were characterized by doublecrystal X -ray diffraction (DCXD) , Hall and photoluminescencemeasurements. The electron mobility of Ga_(0.5)In_(0.5) P reaches 3 300 cm2/ V. s (carrier concentration is1. 4 × 1 0￣(16) cm￣(-3) ) at 7 7 K . The carrier concentration decreases with increasing growth temperature andⅤ/ Ⅲ ratio. It was suggested that P vacancies act as donors. The 77K PL spectrum of Ga_(0.5)In_(0.5) Player grownat 6 50 ℃ and Ⅴ /Ⅲ ratio of 7 0 was dominated by a peak at 1 . 8 2 8 eV with a line width (FWHM) of1 9 meV , and a weak peak 1 . 8 4 9 eV occurred at higher energy side. The difference between PL peakenergy and calculated bandgap energy of GaInP is between 84～ 113 mV. This is probahly related toimpurities and ordered structure in GaInP.