鋁摻雜氧化鋅薄膜電晶體之特性探討

Abstract

著物聯網產業的迅速發展，薄膜電晶體(TFTs)做為顯示開關元件以及電流驅動元件的規格要求也更加嚴格，而傳統的非晶矽(a-Si)薄膜電晶體已漸漸的無法滿足現今的需求。近年來，金屬氧化物薄膜(AOS)做為通道層的薄膜電晶體獲得了許多研究者的關注，尤其以透明的光穿透性(Transparency)、高性能的載子遷移率(Mobility)以及大面積的均勻性(Uniformity)(T.M.U)，使其成為薄膜電晶體通道層絕佳的新穎材料。 然而大規模面板的製造已經嚴重影響人類健康以及環境生態，日前最受歡迎的氧化銦鎵鋅(IGZO)中具有毒性強於鉛(10ppm)的重金屬銦，接觸極限為0.1 mg/m3，相當於0.07ppm，吸入容易導致肺炎甚至肺癌。因此在本論文中，我們使用氧化鋁鋅薄膜(AZO)做為通道層，除了環境議題之外，鋁摻雜氧化鋅對於元件也提供很好的可靠度改善，並且有相關的文獻支持。論文中研究各項製程的變化與機制，並追求氧化鋁鋅薄膜在薄膜電晶體上優秀的T.M.U.電特性。

The rapid development of IOT industry (internet of things) require higher quality of thin film transistors (TFTs), which are used as display control devices and current driver. The traditional amorphous-silicon TFTs can hardly meet the requirement nowadays. In recent years, amorphous metal oxide semiconductor TFTs have attracted a lot of researches. The high transparency, excellent mobility characteristic, and good uniformity (T.M.U.) enable amorphous metal oxide semiconductor film to be a promising candidate material for TFTs. However, the fast growth of display industry causes serious harms to the human and environment. The popular material, IGZO in FPD contains indium metal which is more toxic than plumbum. The poisoning equivalent of indium is 0.08 ppm, which is way more toxic than plumbum which is 10ppm. The inhalation of indium can easily cause serious diseases such as pneumonia and even lung cancer. In this thesis, we use aluminum doped ZnO as the channel layer. Apart from the environment issue, the AZO film supports good bias stress reliability and is supported by many literatures and researches. The AZO TFT is studied by varying the various process parameters and finding the mechanisms. The priority is presuming excellent T.M.U. electric characteristics.