在高ECR 等离子体密度下沉积高质量氮化镓薄膜

目的　研究在电子回旋共振等离子体辅助法生长ＧａＮ 时的离子密度对其质量的影响．方法　用朗缪尔探针测量离子密度，用Ｘ 射线双晶衍射及霍尔测量分析ＧａＮ的质量与性能． 结果离子密度越高，薄膜的质量与性能就越好． 当生长ＧａＮ 时的离子密度为２－０ ×１０１１ ｃｍ － ３ 时，所得ＧａＮ 晶膜的氮镓量比接近于１ ，本底电子密度为３－７ ×１０１８ ｃｍ － ３ ，Ｘ 射线双晶衍射回摆曲线的半高宽为１６ ａｒｃｍｉｎ ． 结论　提高离子密度能明显提高ＧａＮ 的质量与性能

Deposition of High Quality GaN Film Under High ECR Plasma Density

Aim To investigate the influence of ion density(ni) on the deposition of wurtzite GaN films on the substrate of α-Al2O3(0001) by electron cyclotron resonance plasma. Methods Langmuir probe measurement, Double crystal X-ray diffraction and Hall measurement were used. Results The quality of GaN film strongly depended on its growth condition. The higher ion density resulted in a higher amount ratio of N/Ga and a lower background electron concentration of GaN film. When the GaN was prepared in the ion density of 2.0×1011 cm-3, the amount ratio of N/Ga was close to 1, the electron background density was 3.7×1018 cm-3 and its full width at half magnitude(FWHM) was 16 arcmin. Conclusion The quality of GaN film can be improved by raising the plasma density.