以有機金屬氣相磊晶法研究磊晶基板偏角對磷化銦鎵/砷化鎵異質磊晶的影響

Abstract

有機金屬氣相磊晶法由於對磊晶層元素組成比例以及磊晶層厚度有相當優 良的控制能力，而且適合於工業量產，因此已經成為許多三五族化合物半 導體非常重要的磊晶成長技術。GaInP 當它的晶格大小與 GaAs 磊晶基板 相匹配時，其能帶間隙在室溫時約為 1.9 電子伏特，是相當適合製作紅 色發光二極體、半導體雷射、以及異質接面雙極電晶體的光電材料。一般 而言，使用有傾斜角的磊晶基板通常能夠改善磊晶層品質。在此實驗中， 使用常壓有機金屬氣相磊晶系統研究磊晶基板傾斜角度對 GaInP 磊晶層 光學性質與電性的影響，而磊晶基板使用 (100) 偏 [011] 方向，偏角大 小分別為 0度、6度、 10度、以及15度的 GaAs 晶片。隨著傾斜角度的增 大，磊晶層表面越平滑，而 PL 半高寬越窄，電子的遷移率也越高，顯示 磊晶層品質隨基板傾斜角度增大而變得更好。 Due to the excellent control of composition and layer thickness, and the suitability for economical mass production, organometallic vapor phase epitaxy (OMVPE) has become a very important technique for production of high quality epilayers of a numbers of III-V compounds and alloys. GaInP with its lattice constant matched to GaAs substrate has a direct band gap of 1.9eV at room temperature is a promising electronic material for red light-emitting diodes, visible lasers, and heterojuntion bipolar transistors. It's well known that using misoriented substrates could improve quality of epi-layer usually. In our experiment, the effect of substrate on the optical and electrical properties of GaInPpheric pressure OMVPE has been studied, undopedrates with misorientation angles of 0,6,10,and 15 degree toward [011] direction were used. The epi- layers appear to be higher quality with increaning angle of misorientation since their surface morphology are more smooth, PL FWHMs are smaller, and electron mobilitys are higher than those grown on (100) exact substrates.