CAJ | 학술논문

采用分子束外延( MBE)方法在蓝宝石衬底上外延生长m面GaN薄膜。利用原子力显微镜( AFM)、扫描电子显微镜( SEM)分析薄膜表面形貌,发现Ⅴ/Ⅲ族元素比从1∶80降低到1∶90时,外延膜表面均方根粗糙度从13.08 nm降低到9.07 nm。利用光谱型椭偏仪研究m面GaN薄膜,得到了m面GaN薄膜的厚度、折射率和消光系数。拟合结果显示,GaN样品厚度和理论值一致,且Ⅴ/Ⅲ族元素比为1∶90时,所得外延膜折射率较低,透射率大。两种测试方法表明,Ⅴ/Ⅲ族元素比较小的样品晶体质量高。
채용분자속외연( MBE)방법재람보석츤저상외연생장m면GaN박막。이용원자력현미경( AFM)、소묘전자현미경( SEM)분석박막표면형모,발현Ⅴ/Ⅲ족원소비종1∶80강저도1∶90시,외연막표면균방근조조도종13.08 nm강저도9.07 nm。이용광보형타편의연구m면GaN박막,득도료m면GaN박막적후도、절사솔화소광계수。의합결과현시,GaN양품후도화이론치일치,차Ⅴ/Ⅲ족원소비위1∶90시,소득외연막절사솔교저,투사솔대。량충측시방법표명,Ⅴ/Ⅲ족원소비교소적양품정체질량고。
The m-plane GaN film is grown on sapphire substrate by molecular bean epitaxy( MBE) . Surface morpholo-gy is analyzed by the atomic force microscope( AFM) and the scanning electron microscope( SEM) ,These results show that the root mean surface( RMS) roughness of the GaN film decrease from 13.08 nm to 9.07 nm with theⅤ/Ⅲratio down from 1∶80 to 1∶90. Optical properties are investigated by spectroscopic ellipsometry(SE),and the thickness, refractive index and extinction coefficient were obtained. It is found that the thickness of the samples are consistent with the retical values,and a lower refractive index and larger transmittance can be getting when theⅤ/Ⅲratio down to 1∶90. Therefore,the GaN film with smallerⅤ/Ⅲratio has better quality.