近年來太陽能產業發展迅速，太陽能電池製造技術不斷在進步，其中，又以薄膜太陽能電池最受矚目。研究上主要以改善太陽能電池結構，以提高轉換效率，卻很少人針對後段製程方法進行改良與研究。
薄膜太陽能電池在電池製成後進入模組化階段，太陽能模組必須經過電極導帶接合及模組封裝兩大步驟。為了維持模組封裝後太陽能電池穩定的轉換效率，銅帶與薄膜太陽能電池鋁背電極接合需有理想的接合強度。噴墨技術為一種非接觸式的直接製造方法，可精確控制液滴大小與位置、減少接合材料的消耗，因此研究採用無鉛銲錫作為接合材料並透過噴墨製程的結合，並同時搭配模組封裝技術，得到較佳的模組封裝品質。
本研究成功應用噴墨技術噴印Sn3.0Ag0.5Cu合金材料於薄膜太陽能電池模組接合上，研究結果得到較佳的剝離強度其液滴間距至少要小於200 μm，即單位面積下銲錫量須超過50 μg/mm2，所得到的剝離強度即可超越導電銀膠接合的剝離強度。隨著接合強度的增加，太陽能電池效率損失也會跟著下降。本研究所獲得的最佳效率損失為1.5 %，薄膜太陽能電池轉換效率能維持在8.3 %以上。

The photovoltaic industry is fast growing and the fabrication of solar cells has been kept improving. Nowadays, the main type of solar cell development is thin-film solar cells. However, most of studies focus on the solar cell structure to enhance the photovoltaic conversion efficiency rather than improving the solar module packaging process.
For module packaging process, the bus wire bonding and the encapsulation of solar cells are needed in the fabrication of thin-film solar cell. In order to keep stable photovoltaic conversion efficiency after module packaging, good bonding strength is required between copper ribbon and aluminum back electrode of thin-film solar cell. Inkjet printing technology is a non-contact direct fabrication process, which can control precise droplet size and position and reduce material consumption. This study used lead-free solder as bonding material by inkjet printing process and module packaging technology for getting better quality of solar cell modules.
In this study, Sn3.0Ag0.5Cu solders were successfully printed by using inkjet printing technology for bonding of thin-film solar cell modules. The results show that the peel strength of lead-free solder is better than that of silver paste when the dot spacing of lead-free droplets is lower than 200 μm. In other words, the amount of lead-free solder is over than 50 μg/mm2. As the bonding strength increases, the efficiency loss decreases. The optimum results of low efficiency loss degrade 1.5 % and good photovoltaic conversion efficiency is over 8.3 %.

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