本論文主要探討利用化學氣相傳導法成長層狀半導體MoS2摻雜不同過渡性金屬MoS2:X (X=Re,Nb,Fe,Co,Ni) 之相關特性。
在日本National Institute of Advanced Industrial Science, AIST Suenaga 博士研究群協助下，利用掃描式穿透式電子顯微鏡觀察錸及鐵原子在樣品中所在的位置，發現摻雜錸金屬的樣品中，錸原子會取代鉬原子；摻雜鐵的樣品中，鐵原子會聚集成團不均勻地分散在層狀單晶表面上。X光繞射分析，決定樣品主要結構，MoS2:X (X=Re,Nb) 為3R結構；而MoS2:X (X= Fe,Co,Ni) 為2H結構。
光學方面利用電解液電場調制反射光譜來決定直接能隙附近激子A與激子B之躍遷能量。在摻雜錸與鈮之樣品中，激子A與B躍遷能量之分裂量約為150 meV；在摻雜鐵、鈷及鎳之樣品中，激子A與B躍遷能量之分裂量約為200 meV，此差異主要來自於3R與2H之不同結構所致。此外利用光電壓量測技術，決定不同摻雜樣品之間接能隙、激子躍遷能量及雜質相關之吸收訊號。

Electrolyte electroreflectance (EER) and photoresponse spectroscopy in the electrolyte were used to study of doping effects of two-dimensional layered semiconductor MoS2 at room temperature. Single crystals MoS2:X with different dopants X (X=Re, Nb, Fe, Co, Ni) were grown by the chemical vapor transport method using Br2 as transport agent. The electrolytes were 0.5 M H2SO4 or 0.05 M NaI/0.002 M I2/0.05 M H2SO4.
EER measurements were carried out under low field regime. For Nb and Re doped samples only exciton A and B related features were observed. The excitonic transition energies of feature A and B were determined precisely and the splitting of excitonic transition energies for A and B were estimated to be around 150 meV. For Fe/Co/Ni doped samples, the two dominant features located at higher energy side as compared with those observed in the Nb/Re doped samples, an additional feature located below A excitonic transition feature were detected and the splitting of A and B features were estimated to be ~200 meV. The differences between these two groups of samples can be attributed to the formation of two different polytypes 3R and 2H. These results were ascertained by the X-ray diffraction patterns of the samples.
Detailed analyzing photoresponse spectra, the indirect band gap were determined, the excitonic transition energies of A and B features were estimated and the additional features due to different dopants were detected.

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