硒化銅銦(CuInSe2)系列化合物為目前較具潛力之薄膜太陽能電池材料，其直接能隙非常接近太陽光的波長範圍，可吸收大部分太陽光，目前實驗室中轉化效率已達17.6% 。硒化銅銦(CuInSe2)太陽能電池生產方式目前仍以真空製程為主，但其設備成本昂貴，且不利於大面積生產。本研究嘗試以非真空製程方式合成硒化銅銦(CuInSe2)材料，以熱分解法先合成出硒化銦(In2Se3)、硒化亞銅(Cu2Se)與硒化銅(CuSe)粉體，並以硒化銅CuxSe(X=1,2)和硒化銦(In2Se3)為前驅粉體，經固態反應法合成硒化銅銦(CuInSe2)粉體。藉此探討硒化銅CuxSe(X=1,2)和硒化銦(In2Se3)的反應生成機制，並觀察硒化銅銦(CuInSe2)之生成動力學，最後以漿料塗佈方式將前驅粉體披覆在不鏽鋼基板上，經熱壓燒結形成硒化銅銦(CuInSe2)材料，並探討不同燒結溫度對硒化銅銦顯微結構與緻密化之影響。
製備硒化銦(In2Se3)時，主要探討不同配位溶劑的影響，以油胺(OLA)為配位溶劑可以合成出純相之In2Se3粉體，且粒徑大小約為100~200nm，而濃度提高時，將使In2Se3粉末外形改變且晶粒尺寸些微變小；以油酸(OA)和十四烷基酸(MA)為配位溶劑，則會有金屬前驅物Cl離子的殘留而形成InSeCl相，其外觀為板狀或片狀且basal plane方向粒徑大小約為1~2μm。
製備硒化亞銅(Cu2Se)時，當反應溫度較低時，會有Cu2Se和Cu3Se2兩相共存，其中Cu2Se晶粒尺寸約為1~2μm 而Cu3Se2晶粒尺寸均小於0.5μm，隨著反應時間拉長和溫度升高，Cu3Se2二次相則漸漸消失，最後藉由Ostwald ripening方式全部轉變為大顆粒的Cu2Se。
製備硒化銅(CuSe)時，當反應溫度為 180℃及200℃時為純相之CuSe，其型態為三角或六角片狀和板狀，basal plane方向粒徑大小約為1~2μm，隨著溫度升高至220℃時則會有二次相Cu2-xSe之生成，主要原因為在較高溫時油胺(OLA)具有較強之還原性，將Cu2+還原成Cu1+所致。
以In2Se3與Cu2Se為前驅粉體利用固態反應法合成α-CIS之合成溫度較高，其反應最後晶粒大小較接近In2Se3，且在反應過程中可觀察到β-CIS存在，因此推測CIS之生成主要為Cu擴散所主導，其反應活化能為124.3(KJ/mol)且為一維擴散控制。
以In2Se3與CuSe為前驅粉體，利用固態反應法合成α-CIS之合成溫度較低，其反應機構亦主要為Cu擴散所主導，反應活化能為73.2(KJ/mol)且為一維擴散控制，另外在硒氣氛熱處理下，CuSe會相轉變成CuSe2進而與In2Se3反應形成CIS。最後探討不同前驅物對CIS生成活化能之影響，主要由於CuSe2鍵能較Cu2Se弱，且在反應過程中CuSe→CuSe2相變產生之Hedvall effect可提高反應速率，此外CuSe在加熱過程中會產生液相，因此以CuSe與In2Se3為前趨物反應生成CIS之活化能較Cu2Se為低。

The CuInSe2 (CIS) compound is a more potential material of thin film solar cells due to a favorable band gap and relatively high absorption coefficient. Recently, the conversion efficiency of over 17.6% for CIS solar cell has been reported. So far, the vacuum process is still the main method to fabricate the CIS solar cells. However, its cost is too high and it is difficult to produce high quality and large-area CIS films. In this study, we try to synthesize CIS by non-vacuum method. The In2Se3, CuSe and Cu2Se powders were firstly synthesized by thermo-decompositon method. Then, CIS powders were synthesized using CuxSe (X=1,2) and In2Se3 as raw materials via solid state reaction method. Moreover, the CIS formation mechanisms of solid state reaction method using different CuxSe(X=1,2) as raw materials were investigated .Finally, the CIS absorber layers were formed on the stainless steel substrate via tape-casting and hot-pressed sintering method. The effect of annealing temperature after hot-pressed sintering on the microstructure of CIS was investigated.
In the case of In2Se3 powders, the effects of different ligand solvents on the crystalline phase and morphology were studied. It was observed that the In2Se3 phase synthesized using OLA solvent exhibited crystallite size of about 100~200nm and the crystallite morphology depended on the reactant concentration. The InSeCl phase with crystallite size of about 1~2μm was obtained as the OA and MA were used as the solvent.
For the Cu2Se powders, the reaction mechanism was investigated and observed that two crystalline phases (Cu2Se and Cu3Se2 with crystallite sizes of 1~2μm and below 0.5μm, respectively) coexisted at low reaction temperature. The Cu3Se2 crystallites decomposed and then re-precipitated as nano-sized Cu2-xSe crystallites on the surface of the coarser Cu2Se crystallites via Ostwald ripening process as the reaction temperature was increased.
For the CuSe powders, CuSe crystallite phase was observed at reaction temperatures of 180℃ and 200℃.The crystallite morphology are triangular and hexagonal plate with the basal plane diameter of about 1~2 μm. As the reaction temperature was raised, the second phase, Cu2-xSe, will be formed due to the transformation of Cu2+ into Cu+, resulted from the stronger reduction ability of OLA at high temperature.
Finally, the formation mechanisms of CIS powders using CuxSe (X=1, 2) and In2Se3 as raw materials via solid state reaction method were investigated. It was observed that the formation temperature of α-CIS powders synthesized using In2Se3 and Cu2Se as raw materials was higher than that using In2Se3 and CuSe. CuInSe2 formation from the reaction of In2Se3 with Cu2Se and CuSe powders follow diffusion-controlled reactions with apparent activation energies of 124.3 kJ/mol and 73.2 kJ/mol, respectively. Cu2Se or CuSe and In2Se3 phases react and form the intermediate phase, indium-rich β-CIS, and then transform into α-CIS crystallites with the size close to that of the In2Se3 reactant particle based on the TEM results, which indicated that the solid reaction kinetics may be dominated by the diffusion of Cu+ ions. As In2Se3 and CuSe were used as the raw materials, the formation of liquid phase due to the reaction of CuSe and Se and the Hedval effect resulting from the CuSe phase transforming into CuSe2 phase under Se atmosphere both enhanced the reaction rate.

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