Si(111)衬底上生长GaN晶绳的研究

Formation of gallium nitride crystal string on silicon (111) substrate

利用热壁化学气相沉积在Si(111)衬底上获得GaN晶绳,采用傅里叶红外吸收谱(FTIR)、扫描电子显微镜(SEM)、选区电子衍射(SAED)。X射线衍射(XRD)和光致发光谱(PL)对晶绳进行组成、结构、形貌和光学特性分析。初步结果证明:在Si(111)衬底上获得择优生长的六方纤锌矿结构的GaN晶绳。SEM显示在均匀的薄膜上出现φ6μm的晶绳,FTIR显示GaN薄膜的主要成分为GaN同时含有少量的C污染,由XRD和SAED的综合分析得出晶绳呈六方纤锌矿单晶结构,PL测试表明晶绳呈现不同于GaN薄膜的发光特性。

GaN crystal string was deposited on Si (111) substrate by hot - wall chemical vapor depo -sition. Fourier Transform Infrared Transmission (FTIR) Spectroscopy, Scanning Electron Microscopy (SEM), Selected Area Electron Diffraction (SAED), X -Ray Diffraction (XRD) and Photoluminescence (PL) spectroscopy were employed to analyze the composition, surface morphology, structure,, and optical property of GaN layer. FTIR pattern shows the main composition of the film is GaN and it contains trifle carbon contamination. SEM images show a crystal string with a diameter of 6μm appears in the uniform film. XRD, SAED patterns reveal that the formed string is single - crystalline hexagonal gallium nitride. New feature is found in PL pattern of the crystal string, which is different from the bulk GaN films.