论文部分内容阅读
用MOCVD技术在蓝宝石衬底上制备出具有高迁移率GaN沟道层的AlGaN/GaNHEMT材料.高迁移率GaN外延层的室温迁移率达741cm2/(V·s),相应背景电子浓度为1.52×1016cm-3;非有意掺杂高阻GaN缓冲层的室温电阻率超过108Ω·cm,相应的方块电阻超过1012Ω/□.50mmHEMT外延片平均方块电阻为440.9Ω/□,方块电阻均匀性优于96%.用此材料研制出了0.2μm栅长的X波段HEMT功率器件,40μm栅宽的器件跨导达到250mS/mm,特征频率fT为77GHz;0.8mm栅宽的器件电流密度达到1.07A/mm,8GHz时连续波输出功率为1.78W,相应功率密度为2.23W/mm,线性功率增益为13.3dB.
AlGaN / GaNHEMT materials with high mobility GaN channel layer were fabricated on sapphire substrate by MOCVD.The room temperature mobility of high mobility GaN epitaxial layer was 741cm2 / (V · s), the corresponding background electron concentration was 1.52 × 1016cm-3; the room temperature resistivity of unintentionally doped high-resistance GaN buffer layer exceeds 108Ω · cm, the corresponding sheet resistance exceeds 1012Ω / □ .50mmHEMT epitaxial sheet average sheet resistance of 440.9Ω / □, the sheet resistance uniformity is better than 96 %. Using this material, a 0.2μm gate length X-band HEMT power device was developed. The 40μm gate-width device achieves a transconductance of 250mS / mm and a characteristic frequency fT of 77GHz. The device current density of 0.8mm gate width reaches 1.07A / mm , The continuous wave output power is 1.78W at 8GHz, the corresponding power density is 2.23W / mm and the linear power gain is 13.3dB.