【摘要】 在Aixtron 3×2近耦合喷淋式金属有机化学气相沉积反应室中,调节喷淋头与基座之间的距离,制备了7,13,18,25 mm间距的4个InGaN/GaN量子阱样品。利用原子力显微镜(AFM)、X射线衍射(XRD)对样品表面形貌及界面质量进行了表征。研究表明:随着高度的增加,量子阱的表面粗糙度减少,垒/阱界面陡峭度逐步变差,垒层和阱层厚度及阱层In组分含量减少;增加高度至一定值后,量子阱厚度及In组分趋于稳定。此外,对比垒层和阱层的厚度变化,垒层厚度的变化幅度较阱层更为明显。更多还原

【Abstract】 A series of InGaN/GaN multi-quantum wells(MQWs) samples were grown with four different showerhead gap position using Aixtron 3×2 close-coupled showerhead MOCVD system.In the reactor,the showerhead gap position of 7,13,18 and 25 mm were selected to study the effect of gap position on the growth of InGaN/GaN MQWs.The surface morphology,interface quality of samples were characterized by atomic force microscopy(AFM) and X-ray diffraction(XRD).The results show that the roughness of MQWs decreased and the interfacial structure between InGaN and GaN deteriorated simultaneously with the increasing of the showerhead gap position.The thickness of GaN barrier layer and InGaN well layer also decreased,as well as the In composition.However,when the showerhead gap position was enhanced to a certain level,both the variation in thickness of the MQWs and the In composition were reduced and tended to stay stable.Meanwhile,compared with the thickness variation of barrier layer and well layer,the thickness variation of barrier layer was more remarkable.更多还原