蓝宝石衬底上氮化镓薄膜的声表面波特性研究(英文)

Investigation of Surface Acoustic Wave Characteristics in Gallium Nitride Thin Film Grown on Sapphire

研究了蓝宝石上非掺杂GaN,p型GaN和p-GaN/n-GaN 3种薄膜材料的声表面波特性。在p型GaN薄膜中观测到中心频率分别为255MHz和460MHz的Rayleigh模和Sezawa模,插入损耗为-42dB。研究了退火工艺的影响。在N2中800K温度下退火,Rayleigh模和Sezawa模的旁带抑制比分别提高了5.5dB和10.2dB。结果表明具有高阻、足够厚度和高表面质量的GaN薄膜在射频单片集成滤波器领域具有广阔的应用前景。

The characteristics of surface acoustic wave （SAW） on undoped GaN/sapphire, p-GaN/sapphire and p-GaN/n-GaN/sapphire are investigated. For p-GaN grown on sapphire, the Rayleigh wave mode and Sezawa mode are observed with centre frequency of 255 MHz and 460 MHz, and insertion loss of -42 dB are obtained, respectively. In addition, the effect of annealing process is investigated. The sidelobe rejection of the Rayleigh mode and Sezawa mode are improved by 5.5 dB and 10.2 dB respectively after annealing at 800 K in N2 atmosphere. The results show that GaN film with high resistivity, enough thickness and smooth morphology is a very promising material for real RF monolithic integrated filter.