三五族量子井金屬氧化物半導體場效電晶體相關於晶向在低功率高頻的應用

Abstract

根據ＩＴＲＳ，傳統矽半導體的微縮即將遇到瓶頸，因此需要要替代材料來延續半導體的發展。而三五族材料被視為最有潛力的材料之一，因為其特殊的能帶設計，及材料特性，可應用於未來低功率高頻與邏輯的應用。然而傳統高電子遷移率電晶體因為沒有有效的閘極阻擋層，無法有效阻擋閘極漏電流，造成靜態功率耗損過高，但因三五族材料並沒有原生氧化層，因此採用高介電係數的材料做為閘極絕緣體，其較高的介電係數使元件有較高的電容值，且在較厚的物理厚度下仍能與二氧化矽達到一樣的絕緣效果，藉此達成降低漏電流的目的。 在本實驗中，利用氧化鋁作為閘極氧化物，並製作出三五族量子井金屬氧化物半導體場效電晶體，且有效阻擋閘極漏電流的現象，將被討論。此外，利用旋轉閘極方向４５度，造成[１１０]與[１００]兩種閘極方向，藉此改變通道傳輸方向和蝕刻特性，其結果將被清楚地討論。

According to the ITRS, the scaling of traditional Si semiconductor is near the end, and III-V materials are considered as the best candidate to continue the semiconductor development. Due to their excellent carrier transport, and their special bandgap engineering property, III-V materials can be used in future low power high performance logic and RF applications. However, III-V HEMTs do not have effective gate dielectrics to prevent gate leakage currents, causing higher static power dissipation. To reduce the gate leakage current, we employ high-k materials as gate dielectrics of III-V HEMTs. High-k dielectrics have higher capacitance so that it can use smaller physical thickness to achieve the same insulating effect compared to silicon. In this work, Al2O3 was used as the gate dielectrics on InAs QWMOSFET, and the gate leakage current was greatly reduced. Further, the [110]-oriented gate was found to show better electrical characteristics