石英衬底上GaN薄膜沉积及其光学性能的研究

GaN薄膜材料广泛应用于发光二极管(LED)，激光二极管(LD)等光电器件。但是GaN基器件的制备与应用以及器件推广很大一部分取决于其器件的价格，常用的方式是在单晶蓝宝石衬底上沉积制备GaN薄膜样品，单晶蓝宝石衬底晶向择优，可以制备出高质量的GaN薄膜样品，但是单晶蓝宝石衬底价格昂贵，一定程度上限制了其GaN基器件推广使用。如何在廉价衬底上直接沉积高质量的GaN薄膜，满足器件的要求成为研究热点。石英玻璃价格廉价，但是属于非晶体，没有择优晶向取向，很难制备出高质量薄膜样品。本研究采用等离子体增强金属有机物化学气相沉积系统在非晶普通石英衬底上改变氮气反应源流量低温制备GaN薄膜材料。制备之后采用反射高能电子衍射谱、X射线衍射光谱、室温透射光谱和光致光谱对制备的薄膜进行系统的测试分析。其结果表明：在氮气流量适当的沉积参数条件下，所制备的薄膜具有高C轴的择优取向，良好的结晶质量以及优异的光学性能。

Study on the Deposition and Optical Properties of GaN Films at Quartz Substrate

The GaN thin film materials are widely used in light-emitting diode (LED), laser diode (LD) and other optoelectronic devices. But the preparation and application of GaN based device depends largely on its manufacturing cost. At present, because the single crystal sapphire crystal substrate has been merited, the GaN film are commonly deposited on the single crystal sapphire substrate to achieve the high quality GaN films. And because single crystal sapphire substrate is expensive, the GaN devices is limited to use. How to directly deposit high quality GaN films on the cheap substrate and which one meets the requirements of the device have becomed the research hotspot. Quartz glass is cheap as the substrate, but it is not crystal, and it is difficult to deposite high quality thin film samples on quartz glass substrate. In this study, the preparation of GaN thin film materials was prepared by using plasma enhanced metal organic chemical vapor deposition method to change the nitrogen reaction source under normal non-stereotyped quartz substrate at the low-temperature deposition. This research adopts the in-situ reflective high energy electron diffraction spectrum (RHEED), X-ray diffraction spectrum (XRD), Transmission Spectra at room temperature (Transmission Spectra) and room TPS to spectroscopy (PL) to analysis the as-grown GaN films. The results show that the as-grown GaN films show the excellent quality crystallization and optical performance under the proper N₂ flux deposition parameters.