蓝宝石衬底上槽栅型X波段增强型AlGaN/GaN HEMT

X-Band Gate Recess Enhancement-Mode AlGaN/GaN HEMT on the Sapphire Substrate

研制了一款X波段增强型AlGaN/GaN高电子迁移率晶体管(HEMT)。在3英寸(1英寸=2.54 cm)蓝宝石衬底上采用低损伤栅凹槽刻蚀技术制备了栅长为0.3μm的增强型AlGaN/GaN HEMT。所制备的增强型器件的阈值电压为0.42 V,最大跨导为401 mS/mm,导通电阻为2.7Ω·mm。器件的电流增益截止频率和最高振荡频率分别为36.1和65.2 GHz。在10 GHz下进行微波测试,增强型AlGaN/GaN HEMT的最大输出功率密度达到5.76 W/mm,最大功率附加效率为49.1%。在同一材料上制备的耗尽型器件最大输出功率密度和最大功率附加效率分别为6.16 W/mm和50.2%。增强型器件的射频特性可与在同一晶圆上制备的耗尽型器件相比拟。

An X-band enhancement-mode(E-mode) AlGaN/GaN high electron mobility transistor(HEMT) was developed. The E-mode AlGaN/GaN HEMT with 0.3 μm gate-length was fabricated on the 3 inch(1 inch=2.54 cm) sapphire substrate by using low damage gate recess etching technique. The E-mode device exhibits a maximum transconductance of 401 mS/mm,an on-resistance of 2.7 Ω·mm with a threshold voltage of 0.42 V, the current gain cut-off frequency of 36.1 GHz and the maximum oscillation frequency of the 65.2 GHz. At 10 GHz, the E-mode AlGaN/GaN HEMT shows a maximum output power density of 5.76 W/mm and a peak power-added efficiency of 49.1%.The maximum output power density and peak power added efficiency of the depletion-mode(D-mode) device fabricated on the same wafer are 6.16 W/mm and 50.2%, respectively. The RF characteristics of the E-mode device are comparable with those of the D-mode device that fabricated on the same wafer.