本論文提出一種利用過氧化氫(雙氧水)表面處理的方法製作具有鈍化層和金屬-氧化層-半導體的高電子遷移率電晶體。此方法提供了快速、低成本、簡單製程且有效提升元件的特性。雙氧水具有很強的氧化能力，可以氧化氮化鋁鎵表面，以形成氧化層。
實驗結果顯示，經過雙氧水處理7分30秒後，可以改善元件的直流、微波特性和可靠度。閘極不加偏壓時的最大汲極電流，從 337 mA/mm提升到 552 mA/mm；最大轉導值，從 114.9 mS/mm 提升到 135.9 mS/mm；崩潰電壓，從 -79 V 提升到 -132 V；電流增益截止頻率，從 10.52 GHz 提升到 16.14 GHz；最大震盪頻率，從 13.5 GHz 提升到 18.42 GHz；在 2.4 GHz下的最小雜訊，從 2.522 dB 減少到 1.59 dB；在 5.8 GHz下的最小雜訊，從 4.97 dB 減少到 3dB；在 2.4 GHz下的最大輸出功率，從 23.03 % 提升到 33.36 %；在 5.8 GHz下的最小雜訊，從 9.7 % 提升到 16.38 %；虎格係數由 4.33×10-3 減少到 7.49×10-5 ，代表降低了載子在傳輸中受到陷阱捕捉或釋放的機率。在可靠度測試上，在閘極施加-10V的偏壓持續5天，沒有雙氧水氧化製程的元件的最大轉導值會下降40%(跟未施加偏壓的比較)，有雙氧水氧化製程的元件的最大轉導值會下降19%。在脈衝電流-電壓量測上，有雙氧水製程氧化的元件在DC模式和脈衝模式比較上有較小的電流不一致情況，表示改善了RF電流崩潰的現象。

In this work, we present a surface treatment of hydrogen peroxide to fabricate a passivated and metal-oxide-semiconductor high electron mobility transistors. The advantages of this method are fast, low cost, simple process and improve the device characteristics effectively. Hydrogen peroxide has a strong oxidation capability, it can oxidize the surface of AlGaN to form the surface oxide layer.
Experiment results indicate that the oxidation process can improve devices DC, microwave characteristics and reliability. The saturation drain current density (IDSS0) was improved from 337 mA/mm to 552 mA/mm; the maximum extrinsic transconductance (gm,max) was improved from 114.9 mS/mm to 135.9 mS/mm; the breakdown voltage (BVGD) was improved from -79 V to -132 V; the unity current gain cut-off frequency (fT) was improved from 10.52 GHz to 16.14 GHz; the maximum oscillation frequency (fmax) was improved from 13.5 GHz to 18.42 GHz; the minimum noise figure (NFmin) at 2.4 GHz was improved from 2.52 dB to 1.59 dB; the minimum noise figure (NFmin) at 5.8 GHz was improved from 4.97 dB to 3 dB; the Hooge’s coefficient was improved from 4.33×10-3 to 7.49×10-5, the value indicated that reducing the carrier transmission by trap or de-trap. In reliability test, the degeneration of gm,max was 40 % for the device without H2O2 oxidation process and 19 % for the device with H2O2 oxidation process after the gate stress (VG= -10 V) for five days. In pulse current-voltage measurement, smaller current discrepancy between the DC mode and the pulse mode is found in the device with H2O2 oxidation process, it indicates that the problem of RF current collapse is improved.

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