In this letter, we report the first N-polar InAlGaN quaternary back barrier high-electron-mobility transistor (HEMT). The epitaxial device heterostructure was grown by metal organic chemical vapor deposition (MOCVD). Hall measurements of the heterostructure showed a two-dimensional electron gas (2DEG) density of $2.85\times 10^{{13}}$ cm $^{-{2}}$ and a mobility of 1048 cm $^{{2}}\,\,\text{s}^{-{1}}\,\,\text{V}^{-{1}}$ . Transfer length method measurements showed a remarkably low sheet resistance of $179~\Omega /\Box $ in the source-drain direction. A HEMT with a gate length of $0.6~\mu \text{m}$ and source-drain spacing of $3.1~\mu \text{m}$ showed a peak transconductance of 212 mS/mm and a high peak DC drain current of 1.92 A/mm. Small signal measurements of an equivalent HEMT yielded a current-gain cut-off frequency ( $\text{f}_{\text {T}}{)}$ and power-gain cut-off frequency ( $\text{f}_{\text {max}}{)}$ of 18 GHz and 28 GHz, respectively, at peak $\text{f}_{\text {max}}$ bias conditions (VGS = −9 V and VDS = 5 V).

中文翻译：

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N 极 InAlGaN/GaN HEMT 的首次演示

在这封信中，我们报告了第一个 N 极 InAlGaN 四元背势垒高电子迁移率晶体管 (HEMT)。外延器件异质结构是通过金属有机化学气相沉积（MOCVD）生长的。异质结构的霍尔测量显示二维电子气 (2DEG) 密度为 $2.85\乘以10^{{13}}$厘米 $^{-{2}}$移动能力为 1048 厘米 $^{{2}}\,\,\text{s}^{-{1}}\,\,\text{V}^{-{1}}$ 。转移长度法测量显示薄层电阻非常低 $179~\欧米茄/\盒$在源漏方向。栅极长度为的 HEMT $0.6~\mu \text{m}$和源漏极间距 $3.1~\mu \text{m}$显示出 212 mS/mm 的峰值跨导和 1.92 A/mm 的高峰值直流漏极电流。等效 HEMT 的小信号测量产生电流增益截止频率（ $\text{f}_{\text{T}}{)}$和功率增益截止频率（ $\text{f}_{\text {max}}{)}$峰值时分别为 18 GHz 和 28 GHz $\text{f}_{\text {max}}$偏置条件（VGS = −9 V 和 VDS = 5 V）。