本研究探討使用直接升溫法合成銅鋅錫硫 (Cu2ZnSnS4) 奈米級粉體，利用配體交換技術將粉體表面吸附的長碳鏈有機分子交換為短碳鏈有機分子，使其在後續熱處理中較容易被移除，減少薄膜殘碳含量。利用旋轉塗佈法於玻璃基板上塗佈厚度約500 nm的前驅物薄膜，藉由X-ray 繞射儀、EDS及拉曼光譜鑑定薄膜之主要結晶相及化學組成，以確認是否有二次相殘留。接著進行直接硒化熱處理或兩階段熱處理使薄膜中的晶粒成長、緻密化。直接硒化為將CZTS薄膜置於石墨盒中，以硒粉提供盒內硒蒸氣進行硒化促進晶粒成長，而兩階段熱處理為在硒化前先將試片於N2氣氛下進行預燒結1小時，提高前驅物薄膜的緻密性。藉由改變硒化時間、預燒溫度與塗佈次數之搭配，探討不同參數下CZTSSe薄膜的緻密度、顯微結構及化學組成均勻性。
結果發現利用直接升溫法可合成出純相Cubic CZTS奈米粉體，旋轉塗佈2次之CZTS薄膜在硒化條件為500℃- 15 min時有較大的且緻密晶粒及較少二次相，利用霍爾效應分析量測，可獲得載子濃度為7.89×1019 cm-3、遷移率24.3 cm2 V-1 s-1與電阻率為3.27×10-3 Ω-cm之CZTSSe薄膜，而經過250 ℃兩階段燒結之CZTSSe薄膜獲得載子濃度1.21×1019 cm-3，遷移率27.5 cm2V-1S-1，電阻率1.88×10-2 Ω-cm，利用可見光光譜儀量測期能隙值為1.19 eV。使用三電極電化學蝕刻法將薄膜表面之二次相去除再進行光響應量測，於-0.164 V電位(vs RHE)下測得最大光響應電流1.02 mA。

The Cu2ZnSnS4 (CZTS) nanocrystallites were synthesized by the heating-up process. The ligands exchange process was used to reduce the residual carbon on the CZTS particle surface. CZTS thin films with a thickness of about 500 nm were deposited onto the Mo/SLG substrate by using spin coating process. In this study, two methods were used to densify and promote CZTS grain growth: direct selenization and two-stage heat treatment. The direct selenization process is to selenize CZTS thin films in a graphite box with selenium vapor at 500 ℃ to promote the grain growth. The two-stage sintering is to pre-sinter CZTS thin films under nitrogen atmosphere for 1 h to promote the densification before the selenization. The different selenization time, pre-sintering temperature and coating times effects on the electric properties, densification, microstructures and chemical composition uniformity of CZTSSe films were investigated. A p-type CZTSSe film with the hole concentration of 7.89×1019 cm-3, the mobility of 24.3 cm2 V-1 s-1, and the resistivity of 3.27×10-3 Ω-cm can be obtained by direct selenization of the twice spin-coated CZTS film at 500 ℃ for 15 min. The CZTSSe thin film prepared by two-stage heat treatment (pre-sintering temperature: 250oC and selenization temperature: 500oC/15 min) had electrical properties with the hole concentration of 1.21×1019 cm-3, the mobility of 27.5 cm2 V-1 s-1, and the resistivity of 1.88×10-2 Ω-cm. The electrochemical process of cyclic voltammetry can effectively remove Cu2-xSe particles on the CZTSSe surface leading to a higher photocurrent (1.02 mA).

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