在本文中，我們致力研究液相氧化法分別於砷化銦(InAs)與砷化銦鋁(InAlAs)這兩種不同的材料上的特性表現。比較於其他氧化系統，液相氧化法系統不需外加其他能量輔助，只要將晶片所浸入調配好的成長液而其溫度調節保持在30～70oC環境下便能成長均勻氧化薄膜。
在砷化銦的氧化方面，發現在初pH值為4.3 (50oC) 時有較高的氧化速率，再針對其高溫熱處理前後物性與化性之研究。物性方面，熱處理前後，氧化薄膜厚度的差可由橢圓測厚儀得到。此外，使用掃描式電子顯微鏡(SEM)與原子力顯微鏡(AFM)去分析高溫處理後的氧化薄膜粗糙度，我們發現在氮氣環境下進行高溫熱處理後，氧化層薄膜擁有較小的粗糙度；然而，在相同環境700oC的高溫處理會造成氧化層的破壞，使得粗糙度變大。化性部分，透過X光-光譜儀(XPS)來分析該氧化薄膜之化學組成，經過不同溫度的熱處理後，發現氧化層薄膜中的砷訊號減弱或消失而氧化砷的訊號增強了；另一方面，氧化銦有向高束縛能偏移的現象發生。
在砷化銦鋁的氧化方面主要為應用液相氧化法於砷化銦鋁/砷化銦鎵高速電子移動率電晶體形成金氧半高速電子移動率結構的元件特性上，和傳統高速電子移動率電晶體比較下，由於閘極介電層有較大的電位障，因此可以克服通道中撞擊游離現象，改善紐結效應；同時可獲得較佳的飽和特性與功率特性等優點；在操作頻率為2.4 GHz 時，傳統高速電子移動率電晶體可獲得小訊號功率增益為21.05 dB，飽和輸出功率為12.46 dBm，最大功率附加效率為23 %；金氧半高速電子移動率電晶體可獲得小訊號功率增益為18.66 dB，飽和輸出功率為14.32 dBm，最大功率附加效率為34 %。

This paper demonstrates the use of a simple, low cost, and low temperature (30～70oC) liquid-phase oxidation (LPO) technique to prepare native oxide films on InAs and InAlAs, as well as their applications to gate dielectrics. The purpose of this study is to characterize the oxide films with a thermal annealing treatment under an atmosphere of high purity nitrogen.
In InAs, we found the higher oxidation rate at initial pH value is 4.3 (temperature is 50oC). In physical considerations, variations of oxide thickness of the oxide films after annealing were investigated through an ellipsometer. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) were used to analyze the surfaces of oxide films after annealing, after which we found that the lower roughness of the oxide films can be achieved. However, we also found that annealing the destroyed oxide films at 700 oC resulted in increased roughness of such oxide films. In chemical considerations, X-ray photoelectron spectroscopy (XPS) was used for chemical analysis of oxide composition films. After annealing at different temperatures, the peak of As bounded in InAs, was either reduced or became subject to disappearance as the peak of As2O3 is increased. By the way, the peak of In2O3 shifts toward higher binding energy can be observed after annealing.
Another purpose of this study is to characterize the InAlAs/InGaAs metamorphic HEMTs with liquid phase oxidized InAlAs as gate insulators. Compared to the conventional MHEMT, the impact ionization of the channel can be overcome by a thin liquid phase oxidized film as gate insulator. The potential of the lager barrier improved the kink effects. Consequently, large gate voltage and improved power performance were obtained. For the conventional MHEMTs, the measured small-signal power gain, saturated output power, and maximum power-added-efficiency at 2.4 GHz were 21.05 dB, 12.46 dBm and 23 %, respectively. For the MOS-MHEMTs with a gate oxide thickness of 6.3 nm, the measured small-signal power gain, saturated output power, and maximum power-added-efficiency at 2.4 GHz were 18.66 dB, 14.32 dBm and 34 %, respectively.

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