0.15μm GaN HEMT及其应用

A 0.15 μm GaN HEMT and Its Application

报道了毫米波应用的0.15μm场板结构GaN HEMT。器件研制采用了76.2mm(3英寸)SiC衬底上外延生长的AlGaN/GaN异质结构材料,该材料由MOCVD技术生长并引入了掺Fe GaN缓冲层技术以提升器件击穿电压。器件栅脚和集成了场板的栅帽均由电子束光刻实现,并采用栅挖槽技术来控制器件夹断电压。研制的2×75μm栅宽GaN HEMT在24V工作电压、35GHz频率下的负载牵引测试结果显示其输出功率密度达到了4W/mm,对应的功率增益和功率附加效率分别为5dB和35%。采用该0.15μm GaN HEMT技术进行了Ka波段GaN功率MMIC的研制,所研制的功率MMIC在24V工作电压下脉冲工作时(100μs脉宽、10%占空比),29GHz频点处饱和功率达到了10.64W。

A 0.15 μm field plated GaN HEMT for millimeter-wave application is presented in this paper.The AlGaN/GaN heterostructure on 76.2 mm（3 inch） SiC substrate for HEMT fabrication was grown by metal-organic chemical deposition（MOCVD） technology and Fe doped GaN buffer layer was employed to improve the GaN HEMT′s breakdown voltage.Electron beam（e-beam） lithography was used to define both gate footprint and cap of the gate with integrated field plate.Gate recessing was employed to control pinch-off voltage of the device.The 2×75 μm gate width GaN HEMT shows a power density of 4 W/mm with associated power gain and power added efficiency（PAE） of 5.3 dB and 35% respectively,by using load-pull measurements at 35 GHz and 24 V drain bias.Ka band GaN power MMICs were designed and fabricated based on the developed 0.15 μm gate length GaN HEMT technology.The realized Ka band MMIC shows a saturation power of 10.64 W at 29 GHz,operated at 24 V drain bias and pulsed condition with 100 μs pulse width and 10% duty cycle.