金屬誘發側向結晶研究在奈米接觸壓印的非晶矽奈米線

Metal induced lateral growth of Amorphous Si nanowires patterned by Nanocontact printing lithography

劉哲宇(Che-Yu Liu)

指導教授 ： 葉鳳生

國立清華大學/電機資訊學院/電子工程研究所/碩士(2008年)

摘要

本論文的目的為使用奈米接觸壓印技術，將胺基矽烷轉印於非晶矽上並當作蝕刻阻擋層，以製作出奈米級的非晶矽線，其後利用鎳金屬誘發側向結晶技術將非晶矽線結晶化。
首先，為了找到最佳的轉印條件，將胺基矽烷 : 甲醇為1 : 17的沾印用溶液(ink)均勻塗佈在矽晶圓上，其後製備線寬80、100、150、200 nm其線寬與線距為1 : 1與1 : 10的HSQ模仁，將胺基矽烷沾印於模仁上，接著使用奈米接觸壓印技術將胺基矽烷轉印於乾氧基材與非晶矽薄膜上。在乾氧與非晶矽薄膜上做氧電漿的表面處理，以增強胺基矽烷和基材之間的附著力。使用Nanonex-2000機台，試以不同的轉印壓力15~60 psi，於溫度100 oC、時間30 sec的條件下來完成壓印技術。再使用胺基矽烷當作蝕刻阻擋層，使用乾式蝕刻來定義奈米非晶矽線的圖形
再者，使用2~8 nm厚度的鎳金屬鍍覆在非晶矽薄膜上，於550 oC 進行1.5-12 hr的退火後，為了區分出非晶矽與因金屬誘發結晶而形成的多晶矽，使用不同濃度1/9/50/50 -1/9/5/50的蝕刻溶液HF/H2O/HNO3/CH3COOH對sample進行溼蝕刻3-7 s。再將最好的條件用於奈米非晶矽線的結晶化上。FESEM與AFM則被用於觀察轉印後的胺基矽烷圖形與奈米非晶矽線，以及多晶矽的形貌。

關鍵字

奈米接觸壓印技術 ； 鎳金屬誘發側向結晶 ； 奈米非晶矽線

並列摘要

In this thesis, the object is to use aminosilane transferred on amorphous silicon as a hard mask to fabricate amorphous silicon nanowires by nano-contact printing technique and apply nickel induced lateral crystallization technique to fabricate poly Si nanowires.
Firstly, the ink prepared by mixing aminosilane with methanol at volume ratio is 1 : 17, was spin coated on silicon wafer. The ink aminosilane was then transferred on the HSQ molds with line width = 80, 100, 150, and 200 nm and width/space ratio 0.1 and 1. To promote adhesion of aminosilane and substrates, O2 plasma treatment was applied on substrates. The nano-contact printing technique was developed to transfer aminosilane from HSQ mold to dry oxide and amorphous Si film with printing pressure is 15-60 psi and temperature is 100 oC for 30 s. Then the transferred aminosilane pattern was used as a hard mask to define amorphous Si nanowires by dry etching process.
Secondly, the Ni with thickness is 2-8 nm was evaporated on amorphous Si film and Si nanowires. The samples were annealed at 550 oC for 1.5-12 hr, subsequently. In order to distinguish amorphous-Si and poly Si formed by metal induced lateral growth, the etching solution HF/H2O/HNO3/CH3COOH at volume ratio 1/9/50/50-1/9/5/50 was to wet etch the samples for 3-7 s. The above transferred aminosilane, Si nanowries and morphology of poly Si were examined by SEM and AFM.

並列關鍵字

nano-contact printing ； nickel induced lateral crystallization ； amorphous silicon nanowires

參考文獻

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