在互補邏輯電路中，為了要降低靜態功率消耗，n通道和p通道元件必須操作在常關模式，因此本論文旨在開發常關型n通道以及p通道的氮化鋁鎵/氮化鎵異質接面場效應電晶體，並針對兩種磊晶結構進行比較，使其可以應用在互補式金屬氧化物半導體架構中。藉由適當調整蝕刻時間，成功將n通道和p通道元件的操作模式轉變成增強型。
在p通道元件製備流程中，為了降低蝕刻後造成的損傷，我們以稀釋的四甲基氫氧化銨溶液進行表面處理並利用長時間的氮氣退火使其介面缺陷得以改善。此外，在源/汲極金屬沉積前，透過稀釋的鹽酸溶液進行表面處理，確保金屬與半導體界面的氧化物可以更有效的去除，使其歐姆接觸特性得到相當好的改善。
增強型n通道元件的性能如下：在閘極電壓為 1 V 時，最大汲極電流密度達到 39.6 mA/mm，最大跨導值達到 27.89 mS/mm，臨界電壓為 0.19 V，次臨界擺幅與電流開關比為 282.75 mV/dec 與4.8 × 104，閘極漏電流為1.32 × 10-3 mA/mm；增強型p通道元件的性能如下：在閘極電壓為 -2 V 時，最大汲極電流密度達到 -0.17 mA/mm，最大跨導值達到 1.1 mS/mm，臨界電壓為 -2.84 V，次臨界擺幅與電流開關比為 103.1 mV/dec 與5.66 × 105，閘極漏電流為3.17 × 10-6 mA/mm。

In complementary logic circuits, it is crucial to operate the n-channel and p-channel devices in the enhancement mode (E-mode) to minimize static power consumption. Therefore, the aim of this thesis is to develop normally off n-channel and p-channel AlGaN/GaN heterostructure field-effect transistors (HFETs) and compare two different epitaxial structures for their applicability in complementary metal-oxide-semiconductor (CMOS) architecture. By adjusting the etching time appropriately, the operating mode of both n-channel and p-channel devices can be transformed into E-mode.
In the fabrication process of p-channel devices, surface treatment with diluted tetramethylammonium hydroxide (TMAH) solution is performed to reduce the damage caused by etching, followed by a long-duration nitrogen annealing process to improve the interface defects. Additionally, before the deposition of the source/drain metal, surface treatment with diluted hydrochloric acid (HCl) solution is applied to ensure the effective removal of oxide at the metal-semiconductor interface, leading to improved ohmic contact characteristics.
The performance of the E-mode n-channel device is as follows: the maximum drain current density is 39.6 mA/mm at VG = 1 V, the maximum transconductance is 27.89 mS/mm, the threshold voltage is 0.19 V, the subthreshold swing and current on/off ratio are 282.75 mV/dec and 4.8 × 104, respectively, and the gate leakage current is 1.32 × 10-3 mA/mm. The performance of the E-mode p-channel device is as follows: the ID, max is -0.17 mA/mm at VG = -2 V, the gm, max is 1.1 mS/mm, the Vth is -2.84 V, the S.S. and current on/off ratio are 103.1 mV/dec and 5.66 × 105, respectively, and the gate leakage current is 3.17 × 10-6 mA/mm.

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