【摘要】 对采用金属有机化学气相沉积（MOCVD）法在SiC衬底上生长的p型GaN材料进行了研究。p型GaN材料通常采用Mg掺杂来实现，但Mg有效掺杂量的增加会导致材料的空穴浓度提高，表面粗糙度变大、位错密度增加。采用Delta掺杂方式，在Cp₂Mg通入量一定的情况下，通过对温度、压力以及Delta掺杂过程中TMGa通入时间的调控实现了对p型GaN材料掺杂浓度与表面粗糙度和位错密度之间的平衡优化。结果显示，生长温度1 150℃、生长压力400 mbar（1 mbar=100 Pa）、TMGa通入时间40 s的样品均方根表面粗糙度为0.643 nm,（002）晶面半高宽（FWHM）为176.8 arcsec,空穴迁移率为11.8 cm²/（V·s）,空穴浓度为1.02×10¹⁸ cm^-3,实现了电学性能与晶体质量的平衡。更多还原

【Abstract】 The p-type GaN material grown on SiC substrates by metal organic chemical vapor deposition（MOCVD） method was studied.The p-type GaN material is usually achieved by Mg doping.However, the increasing effective doping of Mg may increase the hole concentration, the surface roughness and dislocation density of the material.With Delta doping method, the balance between doping concentration, and surface roughness and dislocation density of the p-type GaN material was optimized by adjusting temperature, pressure and the duration of TMGa introduction during the Delta doping process with a certain amount of Cp₂Mg.The results show that the root-mean-square surface roughness of the sample with a growth temperature of 1 150 ℃,a growth pressure of 400 mbar（1 mbar=100 Pa）,and TMGa introduction time of 40 s is 0.643 nm, the full width at half maximum（FWHM） of the（002） crystal plane is 176.8 arcsec, the hole mobility is 11.8 cm²/（V·s） and the hole concentration is 1.02×10¹⁸ cm^-3,achieving a balance between electrical properties and crystal quality.更多还原