本論文主要探討二硫化鉬(MoS2) 層狀半導體單晶之p型摻雜與表面鈍化製作。實驗上以離子佈植(ion implantation)方式，將具有表面電子聚集的原始表面之二硫化鉬 (簡稱non-fresh MoS2)，以及移除電子聚集層的新鮮表面之二硫化鉬(簡稱fresh MoS2)植入磷離子。經由掃描穿隧式顯微鏡(scanning tunneling microscope, STM)分析晶體表面的電子結構，結果顯示磷離子摻雜能有效地將MoS2的表面電子聚集與多數載子進行補償，形成弱p型。進一步地改變磷離子的摻雜劑量來製作同質p-n接面二極體，但可能由於摻雜劑量的不足，使得在電性上無法觀察到二極體的整流曲線。另外，在表面鈍化方面，為了降低表面的高電子濃度，將non-fresh MoS2置於氧氣環境，利用快速熱退火(rapid thermal annealing, RTA)進行高溫熱處理，並以電導率的變化來探討溫度與時間對MoS2表面鈍化的效益。研究顯示在300℃進行30分鐘的最佳熱處理時，MoS2表面的硫空缺似乎能被氧分子所填補，使non-fresh MoS2的電導率可大幅減少。另外，研究也發現若持續增加熱處理溫度與時間，氧對MoS2的影響可能由鈍化效應轉向摻雜作用，造成電導率有回升的情形。

We investigated the p-type doping and surface passivation of molybdenum disulfide (MoS2) layered semiconductors. Phosphorus ions were implanted into the MoS2 with the non-fresh surface possessing surface electron accumulation (SEA) and the fresh surface without SEA. The electronic structure of the crystal surface was analyzed by scanning tunneling microscopy (STM). The result shows that the doping of phosphorus ions can effectively compensate the SEA to form a weak p-type MoS2. The homogeneous p-n junction diodes were fabricated, but the rectification behavior was not observed. Additionally, surface passivation by thermal treatment in oxygen ambience was conducted to reduce the high electron concentration of the non-fresh MoS2 surface. The effects of annealing temperature and dwell time on the electrical conductivity were investigated. The result shows that the sulfur vacancies in the surface of MoS2 are likely to be filled by oxygen molecules at the optimal dwell time of 30 minutes and temperature at 300 °C.

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