RF-MBE生长AlGaN/GaN二维电子气材料

AlGaN/GaN two-dimensional electron gas materials grown by radio-frequency plasma assisted molecular beam epitaxy

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GaN膜以及AlGaN/GaN极化感应二维电子气材料 .所外延的GaN膜室温背景电子浓度为 2× 10 17cm-3 ,相应的电子迁移率为 177cm2 /Vs;GaN (0 0 0 2 )X射线衍射摇摆曲线半高宽 (FWHM)为 6arcmin .;AlGaN/GaN极化感应二维电子气材料的室温电子迁移率为 730cm2 /Vs ,相应的电子气面密度为 7.6× 10 12 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 0mS/mm (栅长 1微米 ) ,截止频率达 13 .2 5GHz(栅长 0 .5微米 ) ,可在 30

High quality GaN films and AlGaN/GaN polarization induced two dimensional electron gas (2DEG) materials have been 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 177 cm 2/Vs and 2X10 17 cm -3 respectively. The full width at half maximum (FWHM) of (0002) X-ray rocking curve of the GaN film is 6 arcmin. Electron mobility of the 2DEG at room temperature is 730 cm 2/Vs with a sheet electron concentration of 7.6×10 12 cm -2 .The hetrostructure field effect transistors (HFETs) made of the 2DEG materials have a transconductance of 50 mS/mm with an 1 μm gate length, a cut off frequency of 13.25 GHz with 0.5 μm gate length and 20 μm gate width and operation temperature up to 300 ℃.