高品質砷化銦在砷化鎵基板上成長之研究

A Study of High-Quality InAs-Strained Bulk Layer Growth on GaAs by MOCVD

砷化銦成長在砷化鎵基板上經由掃描式電子顯微鏡及勞厄圖像顯示具有單晶品質及良好異質結構介面。使用有機氣相磊晶法成長砷化銦，經由x 光檢測75 莫耳比、600°C 成長溫度下的砷化銦磊晶層其半高寬僅達0.342°。n-like 砷化銦磊晶層在75 莫耳比與600°C 成長溫度下具有2×1017/cm3 的載子濃度與2×103cm2/V-sec 的載子移動率。本質砷化鎵緩衝層在600°C成長溫度下可以藉由有機氣相磊晶法在三五族莫爾比最佳化條件下成功的成長在（100）半絕緣砷化鎵基板上，三五族莫耳比最佳化條件約為100。在最佳化三五族莫耳比條件下砷化鎵成長速率約為每分鐘0.11 微米。類似n 型的砷化銦薄膜亦在600°C 成長溫度下成功的成長在與其形成高應力介面之砷化鎵緩衝層上，三五族莫耳比最佳化條件亦約為75。砷化銦薄膜在砷化鎵緩衝層上之成長速率約為每分鐘0.12 微米，但是成長厚度不能超過2.4 微米，否則將產生明顯的缺陷。雖然砷化銦∕砷化鎵應力量子井會造成能階變化，但是砷化銦∕砷化鎵量子井應用於光電元件的價值性高，本研究利用有機氣相磊晶法高速成長出薄膜厚度可控性高、介面品質可控性高、摻雜可控性顯著之砷化銦∕砷化鎵異質介面，因此該技術將可以應用於雷射元件製造業之生產。 The interface between GaAs and InAs layers possesses good hetero-structure epitaxial growth by using MOCVD (metal organic chemical vapor deposition) method. The main peak of an InAs X-ray is sharp, the full-width half-maximum (FWHM) being narrow for the V/III ratio near 75, at only about 0.342°. A Laue pattern and a scanning electron microscopy image both show the InAs layer grown on a GaAs layer with a single crystalline structure. The i-GaAs buffer layer is grown on a (100) semi-insulated GaAs substrate at 600°C at a mole fraction ratio of group V to group III with an optimum of 100. The growth rate of the GaAs layer is 0.11 m/min. The n-like InAs layer formed as a high-strained layer is also grown on the GaAs buffer layer at a substrate temperature of 600°C by a V/III mole fraction ratio with an optimum of 75. Consequently, the growth time of the InAs layer cannot exceed 20 minutes. The growth rate of the InAs layer is about 0.12 m/min at a growth temperature of 600°C. A carrier concentration of 2×1017/cm3 and a Hall mobility of 2×103cm2/Vsec were obtained for an undopant n-like InAs prepared on a GaAs substrate at a growth temperature of 600°C at a group V/III ratio of 75.