摘要
用射频等离子体辅助分子束外延技术 (RF- MBE)在 C面蓝宝石衬底上外延了高质量的 Ga N膜以及 Al Ga N/Ga N极化感应二维电子气材料 .所外延的 Ga N膜室温背景电子浓度为 2× 10 1 7cm- 3 ,相应的电子迁移率为 177cm2 /(V· s) ;Ga N (0 0 0 2 ) X射线衍射摇摆曲线半高宽 (FWHM)为 6′;Al Ga N/Ga N极化感应二维电子气材料的室温电子迁移率为 730 cm2 /(V· s) ,相应的电子气面密度为 7.6× 10 1 2 cm- 2 ;用此二维电子气材料制作的异质结场效应晶体管 (HFET)室温跨导达 5 0 m S/mm (栅长 1μm) ,截止频率达 13GHz(栅长 0 .5 μm)
High quality GaN films and AlGaN/GaN polarization induced two dimensional electron gas (2DEG) materials are grown on (0001) sapphire substrates by radio frequency plasma assisted molecular beam epitaxy (RF MBE) technique.Electron mobility and background electron concentration of the grown GaN film at room temperature are 177cm 2/(V·s) and 2×10 17 cm -3 ,respectively.The full width at half maximum (FWHM) of (0002) X ray rocking curve of the GaN film is 6arcmin.Electron mobility of the 2DEG at room temperature is 730cm 2/(V·s) with a sheet electron concentration of 7 6×10 12 cm -2 .The Heterostructure field effect transistors (HFETs) made of the 2DEG materials have the transconductance of 50mS/mm with the gate length of 1μm and the cut off frequency of 13GHz with the gate length and width of 0 5μm and 20μm,respectively.
