本論文是以化學氣相傳導法利用三氯化碘(ICl3)為傳導劑成長β-In2S3及物理氣相傳輸法成長InS及In6S7來得到此硫化銦系列半導體之晶體，同時對此系列晶體之特性藉由光學量測的方式對其特性加以研究及討論。由X-ray繞射及拉曼量測之分析可以確定此系列單晶為單相化合物及其結構。
粉末X-ray繞射分析可得之所成長出來In2S3為β相且為四方晶系(tetragonal)而In6S7為單斜結構(monoclinic)，計算後所得之晶格常數和文獻比對均為符合。藉由拉曼量測的技術並配合過去文獻比對，可確定InS為斜方晶系(orthorhombic)其空間群為D122h。在光學特性方面利用熱調制光譜、壓電調制光譜及吸收光譜得知在此硫化銦系統中InS為間接能隙半導體，而β-In2S3及In6S7均為直接能隙半導體。其能隙在300K時分別為1.85 eV、1.935 eV和0.93 eV。
在β-In2S3部份除了在近能隙的躍遷使用熱調制光譜觀察到為1.935 eV之外，同時藉由光激發螢光光譜、光電導實驗及表面光電導量測也發現到在能隙之上有來自表面態的貢獻而能隙之下也有躍遷訊號，其來源為本身晶體的缺陷。
在能源材料In6S7的研究中利用壓電調制及穿透光譜得到此化合物為一直接能隙半導體其能隙在300K實為0.93 eV。而光激發螢光光譜的量測中觀察到在近能隙處有一激子的訊號來源，因此更進一步證明此材料為直接能隙半導體。同時藉光電轉換實驗可證明此材料對於太陽光譜的吸收可擴展至近紅外的區域。
最後在InS晶體討論中使用了吸收光譜及調制光譜的技術證明此半導體為間接能隙半導體其間接能隙位置於300K時為1.85 eV，在壓電調制的實驗當中和文獻相比對亦發現此材料的直接躍遷訊號在室溫下為2.42 eV。
綜合以上幾點可以得知此系統中使用不同的成長溫度條件和較小化學計量差距下，會有豐富的結構、能隙及特性的不同。同時也提出此三種晶體可能性的能帶結構。

III-VI indium sulfide compound semiconductors have been grown by chemical vapor transport (CVT) method using ICl3 as a transport agent. The physical vapor transport (PVT) method was also used. Detailed characterization of the materials were carried out by using X-ray diffraction, Raman scattering, absorption, modulation reflectance, photoluminescence (PL), surface photoresponse (SPR) and photoconductivity (PC) techniques.
X-ray analysis confirms that In2S3 crystal is of β phase tetragonal structure, while In6S7 crystal is monoclinic. Raman measurement reveals that InS crystallizes in orthorhombic structure with space group D122h. Optical property of InS, β-In2S3 and In6S7 was characterized using thermalreflectance (TR), piezoreflectance (PzR) and absorption measurements, which showed that InS is an indirect semiconductor, and those of β-In2S3 and In6S7 are direct semiconductors. The band gaps of InS, β-In2S3 and In6S7 at 300 K are determined to be 1.85 eV, 1.935 eV and 0.93 eV, respectively.
For β-In2S3, the PC and SPR measurements have indicated not only the band-edge transitions but also transition features below and above the band edge. The below band-edge transition can be ascribed to the present of defect states. The defect and above-band-edge transition emissions of β-In2S3 crystal were characterized experimentally by PL measurements.
Optical evidence of band gap, band-edge exciton, and white-light photoelectric conversion for the solar-energy material In6S7 has been demonstrated. The room temperature direct gap of In6S7 at 0.93 eV is extremely suitable for absorption of full sunlight spectrum extension to the near infrared region.
The optical properties of InS were also examined. The band-edge was evaluated and identified using PzR and absorption measurements. Absorption measurement indicated indirect semiconducting nature for InS with a room temperature indirect band gap of 1.85 eV. The room temperature direct band gap of InS was determined to be 2.42 eV by the PzR measurement.
In this study, we have demonstrated the ability to synthesize In-S compound semiconductors either in the forms of indirect band gap orthorhombic InS or direct band gap tetragonal β-In2S3 or direct band gap monoclinic In6S7 by using different growth conditions and stoichiometry in the system. These material systems have exhibited quite different structural and optical characters. From the experimental observations, band diagrams for the as-grown InS, β-In2S3 and In6S7 were constructed and presented.

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