C波段0.75mmAlGaN/GaN功率器件

10×75μm×0.8μm AlGaN/GaN Power Devices on Sapphire Substrate with Output Power Density of 2.4W/mm at 4GHz

研制并测试了以蓝宝石作衬底的10×75μm×0.8μmAlGaN/GaN微波器件,采用等离子增强气相化学沉积的方法生长了250nm的Si3N4形成钝化层,直流特性从0.56A/mm上升到0.66A/mm,跨导从158mS/mm增为170mS/mm,截止频率由10.7GHz增大到13.7GHz,同时在4GHz下,Vds=25V,Vgs=-2.5V,输出功率由0.90W增至1.79W,输出功率密度达到2.4W/mm.钝化有效地改善了器件的输出特性,减小和消除了表面寄生栅对器件的影响.

This paper reports an high performance AIGaN/GaN power heterostructure field effect transistors（HEMTs） on sapphire substrate with total gate width of 0.75mm. After surface passivation with 25nm Si3N4 based on the plasma enhanced chemical vapor deposition （PECVD） method,drain current and transconductance of AIGaN/GaN H EMT increase from 560mA/ mm and 158mS/mm to 660mA/mm and 170mS/ram. More increase of output power from 29.54dBm to 32.52dBm. The surface passivation effectively eliminates or reduces the defects limiting both the RF and power characteristics of AIGaN/GaN HEMT.