使用氮化鋁及閘極介電質成長後電漿處理法改善三五族砷化銦鎵場效電晶體元件特性之研究

Abstract

未來先進互補式金屬氧化物半導體將會使用新穎的通道材料、幾何結構、載子傳導機制。當傳統以矽材料為主的互補式金屬氧化物半導體科技發展接近微縮極限，將考慮以三五族化合物半導體作為通道材料使摩爾定律繼續往前發展。然而，三五族化合物缺少如矽基板材料穩定的原生氧化物。如果使用三五族材料的金氧半場效電晶體，則需要適當的閘極介電質。高品質的閘極介電質，不僅可以提供較佳的閘極控制能力，更可進一步提升元件特性。為了達到高效能三五族元件，本實驗以砷化銦鎵場效電晶體為主，使用三氧化二鋁以及二氧化鉿作為閘極氧化物，導入氮化鋁介面活性層及閘極介電質成長後電漿處理法。由於此兩種方法使用原子層化學氣相沉積系統製程，可以避免三五族材料與空氣接觸汙染產生缺陷，更可以應用於不同的元件結構如：鰭式場效電晶體(FinFET)、全包覆式閘極電晶體(Gate-All-Around)、或是應用於其他閘極線寬小於十奈米之電晶體設計等等。

Advanced future CMOS technology will rely on the innovation of materials, architecture, and transport theory. As conventional silicon complementary metal oxide semiconductor (CMOS) scaling approaches end of the roadmap, III-V compound semiconductors have been considered as an alternative technology to continue transistor size scaling. Unlike Si, III-Vs are lack of high-quality native oxide, which makes Si as the mainstream VLSI technology. Thus, III-V MOSFET requires appropriate gate dielectrics. It is worth pointing out that a good high-k dielectric should not only provide better gate controllability but also enhance devices output characteristics. In order to achieve high performance III-V devices, this study demonstrates Al2O3 and HfO2 on III-V nMOSFETs with interfacial passivation layers AlN and post remote-plasma (PRP) treatment. Because this two passivation methods are in situ atomic layer deposition (ALD) process, these can not only prevent the III-V surface exposure to the air but also be easily utilized to various device architectures such as FinFET, gate-all-around, and other kinds of sub-10 nm transistors.