For the fabricated AlGaN/GaN high electron mobility transistors (HEMTs) with different Ohmic contact widths, the gate-channel electron mobility is obtained experimentally. Mobility curves show very different values and trends. This phenomenon is investigated with the scattering theory in AlGaN/GaN HEMTs. The reason for the different mobility curves is found to be attributed to the different polarization charge distributions at the AlGaN/GaN interface. The AlGaN/GaN HEMT with a smaller Ohmic contact width corresponds to positive additional polarization charge near the Ohmic contact. The AlGaN/GaN HEMT with a larger Ohmic contact width corresponds to negative additional polarization charge near the Ohmic contact. Changing the Ohmic contact width will be a new dimension to optimize the characteristics of AlGaN/GaN HEMTs effectively.

中文翻译：

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AlGaN/GaN HEMTs中与欧姆接触宽度相关的电子迁移率研究

对于制备的具有不同欧姆接触宽度的AlGaN/GaN高电子迁移率晶体管（HEMT），通过实验获得了栅沟道电子迁移率。流动性曲线显示出非常不同的值和趋势。用 AlGaN/GaN HEMT 中的散射理论研究了这种现象。发现迁移率曲线不同的原因是由于 AlGaN/GaN 界面处的极化电荷分布不同。具有较小欧姆接触宽度的 AlGaN/GaN HEMT 对应于欧姆接触附近的正附加极化电荷。具有较大欧姆接触宽度的 AlGaN/GaN HEMT 对应于欧姆接触附近的负附加极化电荷。改变欧姆接触宽度将是有效优化 AlGaN/GaN HEMT 特性的新维度。