本論文利用化學氣相傳導法成長出硫化錫(SnS)與硒化錫(SnSe)之單晶，利用能量散佈儀確認元素成分比例符合。透過X光繞射、穿透式電子顯微鏡與拉曼散射光譜可確認兩者均為正交晶系(Orthorhombic)結構，三晶軸方向夾角為90度。晶格常數SnS為a = 4.2582Å、b = 3.9860Å、c = 11.4258Å；SnSe為a = 4.4499Å、b = 4.1569Å、c = 11.6091Å。
光學實驗部分，根據拉曼散射光譜所得出的結果，硫化錫與硒化錫會因光的偏振方向差異而使某些震動訊號呈現選擇定律，因此晶軸具有極化特性。在光穿透實驗與熱調制反射光譜中，兩者亦會因為沿著不同晶向進行極化而使近能隙的兩個躍遷訊號有消長現象，亦證明了四六族半導體SnX系列材料具有光學異向特性。
在SnS的極化熱調制反射光譜中，光偏振方向與材料b軸相同時，會有能隙躍遷訊號在1.20eV與直接躍遷訊號在1.616eV；但光偏振方向與材料b軸垂直時，1.616eV的直接躍遷訊號會消失，能隙躍遷訊號變窄且位置位於1.15eV。因光穿透與調制光譜兩項光學實驗結果相符合，可以認定SnS為直接能隙半導體。
同樣在SnSe的極化熱調製反射光譜中，光偏振方向與材料b軸相同時，會有能隙躍遷訊號在0.99eV與直接躍遷訊號在1.258eV和1.374eV；但光偏振方向與材料b軸垂直時，兩支直接躍遷訊號會消失，能隙躍遷訊號變窄且位置位於0.94eV。因光穿透與調製光譜兩項光學實驗結果也相符合，亦可認定SnSe也為直接能隙半導體。
電學實驗部分，利用線性段的I-V 曲線並透過些許公式可計算出導電率。SnS的導電率為2.76×10-1 (-cm)-1，SnSe為1.944×10-1 (-cm)-1，並且經由對樣品照光發現光電流的增加趨勢，可以看出SnS與SnSe在照光後光電流與光電壓增加。進一步透過表面光電壓(SPV)實驗、熱探針實驗，證實兩者均為光電材料與熱電材料，並且為p型半導體材料。經過一連串的實驗中，證實兩者都具有光電響應與熱電響應，
極具有潛力發展在光電元件與熱電元件上的應用。

IV-VI compound semiconductors tin monosulfide and tin monoselenide have been grown by chemical vapor transport (CVT) method using I2 as a transport agent. Detailed characterization of the materials were carried out by using energy-dispersive X-ray spectroscopy (EDS) , X-ray diffraction (XRD) , high-resolution transmission electron microscopy (HRTEM) , Raman scattering techniques. The SnX material crystal structure is orthorhombic. Lattice constants of SnS are a = 4.2582Å, b = 3.9860Å, c = 11.4258Å and those of SnSe are a = 4.4499Å, b =4.1569Å, c = 11.6091Å, respectively.
According to Raman result, the vibration modes of SnS and SnSe show selection rule for the linearly polarized lights along a and along b axis. The SnX (X=S, Se) shows in-plane anisotropy on the c plane. From the results of transmittance and thermoreflectance, the band gaps and direct interband transitions also show polarization dependency with the linearly polarized lights along a and along b axis. In polarized thermoreflectance (PTR) experiment of SnS, it has a direct band-gap transition at 1.20 eV and an interband transition at 1.616 eV when E//b. For E⊥b, the 1.616 eV transition disappears, the direct-gap transition feature becomes narrow and its energy position shifts to 1.15 eV. Owing to the results of transmittance and thermoreflectance are comparable near band edge, we can infer that SnS is a direct band gap semiconductor. For the PTR result of SnSe, the direct band gap transition is at 0.99 eV and two transitions are at 1.258 eV and 1.374 eV when E//b. For the E⊥b condition, two transitions of 1.258 eV and 1.374 eV disappear, while direct-gap transition become narrow and shifts to 0.94 eV. The SnSe is also a direct band gap semiconductor.
For electrical measurements, the conductivity of SnX was determined to be 2.76×10-1 (-cm)-1 for SnS and 1.944×10-1 (-cm)-1 for SnSe, respectively. The surface photovoltage (SPV) measurements of SnS and SnSe also show in-plane anisotropy of the photovoltaic response spectra with E//b and E⊥b conditions. The SnX (X=S, Se) also reveal thermos-electric voltage generated from the samples by hot-probe measurements. From the polarity of thermoelectric voltage, the SnS and SnSe are p-type semiconductors. According to the optical and electrical measurement results, the SnX (X=S, Se) can have both photovoltaic and thermoelectric capability, and which possess the potential for application in the future optoelectronics and energy devices.

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