以金屬誘發側向結晶之多晶矽薄膜電晶體的製作與分析

Abstract

在本篇論文中，我們對以金屬誘發側向結晶製程(MILC)之多晶矽薄膜電晶體(Poly-Si TFT)進行研究。首先在材料分析部分，我們量測並分析了薄膜厚度、製程溫度與金屬引洞尺寸對MILC製程的影響，並運用光學與電子顯微鏡對MILC實際長度與薄膜結構進行分析。而在實際元件製作部分，我們用兩種不同製程製作MILC TFT以分析製程的不同對元件特性的影響，並與固向結晶法(SPC)製作之TFT進行比較，而同時，我們也研究了元件尺寸對MILC Poly-Si TFT電性的的影響。最後，我們利用本實驗室發展出的特殊結構HC-TFT對離MILC金屬引洞不同位置的MILC薄膜的電性進行分析，並萃取其汲極漏電流的活化能(Ea)以及狀態密度(DOS)做進一步的分析。

In this thesis, we investigate the material and electrical properties of poly-Si TFTs prepared by metal induced lateral crystallization (MILC) process. The relations between MILC length and film thickness, process temperature, and the dimensions of MILC seeding window were measured and discussed. The OM and SEM pictures after secco etching were used to probe the MILC length and film structure. Poly-Si TFTs fabricated by two kinds of MILC processes as well as SPC process were analyzed and compared. Characteristics of MILC TFTs with various dimensions were characterized to understand the impact of geometrical parameters of the device structure in affecting the device performance. We also employed a novel tester named HC-TFTs to resolve the location dependence and impact of the MILC poly-Si film on device characteristics. Finally, the characteristics of these TFTs, such as transfer characteristics, density of states (DOS), and the activation energy of leakage current (Ea), were also measured and discussed