本論文利用擴散驅入原理開發一種新穎製成高鍺比例矽鍺之方法，達到磊晶不易沉積的高鍺比例之矽鍺單晶薄膜，並用於製作閘極全環式奈米片P型電晶體。
擴散製程早期普遍用於IC生產中的半導體摻雜使用，先進的IC生產中實際已很少使用擴散摻雜製程，但我們可以利用擴散中分子的熱運動會使物質從濃度高移向濃度低區之特性，配合遮蓋層將矽與鍺結合成矽鍺薄膜。
我們使用爐管的高溫長時退火製程，將濺鍍在SOI基板上的鍺原子驅入擴散進矽薄膜裡，經由改變各種條件，如溫度、時間和遮罩層等，再透過X射線光電子光譜儀、X射線繞射分析儀及穿透式電子顯微鏡觀察矽鍺薄膜之擴散情形、結晶狀況與應力分佈，發現使用氮化矽遮罩層在900oC下退火12小時，可得到單晶且擴散最為均勻之矽鍺薄膜，且鍺比例最高可達到70%左右。
將驅入擴散製作之高鍺比例之SiGeOI基板應用於環繞式閘級奈米片通道P型金氧半場效電晶體上，由於單晶和鍺濃度的提升，我們得以提高P型元件之驅動電流。一般環繞式閘級矽鍺奈米片通道場效電晶體製程需將矽鍺薄膜磊晶在SOI基板上，再透過乾式和高選擇比濕式蝕刻將通道懸空，而我們可將單晶矽鍺直接沉積在二氧化矽上，這是磊晶做不到的，只將二氧化矽作為犧牲層，需要透過簡單的濕式蝕刻即可懸空奈米片通道，大大地降低了製程複雜度。

In this study, we propose a new method to form a silicon germanium film in various ratios by drive-in diffusion, which can be applied to fabricate Gate-all-around nanosheet p-MOSFET. The result can achieve a single crystal silicon germanium film with high germanium proportion which cannot be easily deposited by epitaxy technology.
In traditional, the diffusion process which was commonly used for semiconductor doping in IC fabrication. Recently, the diffusion doping process has rarely been used. Thanks for the thermal motion, we can form a silicon germanium film with the capping layer by mixing silicon and germanium via drive-in.
The germanium atoms of the silicon germanium film which is sputtered on the silicon-on-insulator substrate drive in the silicon film by furnace process, and we tried various conditions, such as temperature, time, and capping layer. Through X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Transmission electron microscope (TEM), we observed the diffusion distribution, crystallization state and stress distribution of the silicon germanium film. At last, we obtained the most homogeneous single crystal silicon germanium film that using the silicon nitride capping layer annealed at 900oC for 12 hours, and the proportion of germanium can reach up to about 70%.
The SiGeOI with high germanium proportion by drive-in diffusion is applied to the Gate-all around nanosheet pMOSFET. Due to the single crystal and the increase of the germanium concentration, the drive current of the P-type transistors can be enhanced. In general, the processes of gate-all-around silicon germanium nanosheet channel field effect transistors require to epitaxy silicon germanium film on the SOI substrate, and then the channel is released by dry etching and high selective wet etching. We can fabricate single crystal silicon germanium directly deposited on silicon oxide, which cannot be achieved by epitaxy. Furthermore, the nanosheet channel, which only silicon oxide is used as the sacrificial layer, can be released by simple wet etching. It reduces the complexity of the process greatly.

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