使用介電質電漿處理法製作高效能砷化銦鎵三維金氧半場效電晶體達未來低耗能高速邏輯元件應用

Abstract

在這項研究中，我們製造了砷化銦鎵(InGaAs)的鰭式場效電晶體(FinFET)和全包覆式閘極場效電晶體(GAA-FET)，利用閘極介電質成長後電漿處理法(in situ post remote-plasma treatment)來提升此元件的特性。我們使用精準的乾蝕刻和濕蝕刻技術來製造非三維式的元件，可以蝕刻出最小的鰭式寬度為20奈米和通道長度為50奈米的鰭式場效電晶體元件及最小奈米線寬度10奈米和通道長度50奈米的全包覆式閘極場效電晶體。使用遠程電漿處理法，鰭式電晶體體及全包覆式閘極場效電晶體可以改善元件特性還有閘極介電層的品質，使鰭式場效電晶體和全包覆式場效電晶體的開關特性比為4和6個數量級。從我們元件的微縮指標(scaling metric)來看，顯示出在我們製程中，鰭式場效電晶體和全包覆式閘極電晶體有優秀抑制短通道效應的能力。 此外，我們還對鰭式場效電晶體及全包覆閘極場效電晶體做了可靠度的量測，我們藉由正偏壓溫度不穩定性(PBTI)方法來分析元件，我們發現經過電漿處理法的元件，可以提升氧化層內的鍵結能量和減少陷阱密度(density of trap)，在高溫高壓的條件下元件有較小的衰退速度，顯示出有較好的可靠度特性，最後藉由PBTI分析和公式的推測，經過電漿處法的元件在85°C下操作十年，臨界電壓下降30mV，鰭式場效電晶體和全包覆式閘極場效電晶體的驅動電壓接近0.32V和0.36V。

In this study, we have demonstrated In0.53Ga0.47As FinFETs, GAA-FETs utilizing plasma treatment. Using dry and wet etching techniques, 3D MOSFET devices, owning to smallest LCH of 50 nm and WFin of 20 nm for FinFET and smallest LCH of 50 nm and WNW of 10 nm for GAA-FET, have been fabricated and characterized. The treatment provides much better electrostatic control and improves the electrical characteristics. Optimizing oxide and interfacial qualities by PRP treatment, a high ION/IOFF of ~ 104 and ~106 have been obtained for In0.53Ga0.47As FinFET and GAA-FET, respectively. Scaling metrics study for InGaAs FinFETs & GAA-FETs are also systematically studied with LCH from 170 down to 50 nm, WFin from 60 down to 20 nm and WNW from 60 down to 10 nm which shows an excellent immunity to short channel effects. In addition, to evaluate the impacts of PRP treatment on the reliability properties of III-V-based 3D MOSFETs, the positive bias temperature instability (PBTI) has also been carried out. The In0.53Ga0.47As FinFET & GAA-FETs treated by PRP treatment illustrate better reliability performance and less degradation for a long-term stress at large bias voltage and high operate temperature. This can be attributed to stronger bonding energy and lower density of trap states in the high-k gate dielectric. The PBTI results also show that, for an operation lifetime of 10 years at 85 °C, the In0.53Ga0.47As FinFETs and GAA-FETs achieved in this study with PRP treatment would be ensured to operate at an overdrive voltage of 0.32 and 0.36 V, respectively.