This paper reports pulsed DC and RF characteristics of GaN high-electron-mobility transistors (HEMTs) on a silicon substrate under external mechanical tensile strain. Tensile strain enhanced two-dimensional electron gas (2DEG) density resulted in increasing I D , f T and f max at CW measurement. Eliminating self-heating by pulse measurement, DC and RF characteristics between flat and bend devices were slightly increased for small-width devices, and decreased for wide-width devices. This was because maximum electron drift velocity was reduced by a hot phonon effect while 2DEG density increased by tensile strain for wide-width devices. Results indicated that the tensile strain on thinner substrates decreased the DC and RF performances of wide-width GaN-based RF power devices. This phenomenon should be considered while using GaN-based RF power devices for compact packages, especially in high-power applications.

中文翻译：

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单轴拉伸应变下硅衬底上的AlGaN / GaN高电子迁移率晶体管

本文报道了在外部机械拉伸应变下，硅衬底上的GaN高电子迁移率晶体管（HEMT）的脉冲DC和RF特性。拉伸应变增强了二维电子气（2DEG）的密度，导致CW测量时ID，f T和f max增大。通过脉冲测量消除自热，扁平和弯曲设备之间的DC和RF特性对于小宽度设备略有增加，而对于宽宽度设备则有所下降。这是因为对于宽宽度器件，最大的电子漂移速度由于热声子效应而降低，而2DEG密度因拉伸应变而提高。结果表明，在较薄基板上的拉伸应变降低了宽宽度GaN基RF功率器件的DC和RF性能。