Low-frequency noise (LFN) performances are investigated in a normally-off GaN metal-oxide-semiconductor field-effect transistor (MOSFET) fabricated by utilizing the tetramethylammonium hydroxide (TMAH) wet etching. The normalized power spectral densities ( $\text{S}_{Id}/\text{I}_{d}^{2})$ are measured and perfectly matched with both the correlated mobility fluctuations (CMF) and Hooge mobility fluctuations (HMF) noise models. From the curves of ( $\text{S}_{Id}/\text{I}_{d}^{2})$ dependent on the gate overdrive voltage (V _g – $\text{V}_{th})^{-1}$ , it is also confirmed that the mobility fluctuations prevail in the fabricated GaN device. The calculated Hooge constants ( $\alpha _{H}$ ) according to the (V _g – $\text{V}_{th}$ ) are obtained to be 10 ⁻² ~ 10 ⁻³ . The reason for the dominance of the mobility fluctuations and the relatively low $\alpha _{H}$ is attributed that the TMAH wet etching effectively removes the plasma etching damage and fully recovers the crystal quality of GaN channel.

中文翻译：

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使用四甲基氢氧化铵湿法刻蚀的常关型GaN MOSFET的迁移率波动

在利用四甲基氢氧化铵（TMAH）湿法刻蚀制造的常关型GaN金属氧化物半导体场效应晶体管（MOSFET）中研究了低频噪声（LFN）性能。归一化功率谱密度（ $ \ text {S} _ {Id} / \ text {I} _ {d} ^ {2}）$ 被测量并与相关迁移率波动（CMF）和Hooge迁移率波动（HMF）噪声模型完美匹配。从（ $ \ text {S} _ {Id} / \ text {I} _ {d} ^ {2}）$ 取决于栅极过驱动电压（V _G – $ \ text {V} _ {th}）^ {-1} $ ，还证实了在所制造的GaN器件中普遍存在迁移率波动。计算的Hooge常数（ $ \ alpha _ {H} $ ）根据（V _G – $ \ text {V} _ {th} $ ）获得为10 ^-2〜10 ^-3 。迁移率波动占主导地位且相对较低的原因 $ \ alpha _ {H} $ 这归因于TMAH湿法蚀刻有效地消除了等离子体蚀刻的损害，并完全恢复了GaN沟道的晶体质量。