傳統化石燃料在不斷開採下愈來愈少的情況下，綠色能源的使用逐漸成為全球趨勢焦點，其中又以太陽能電池為熱門替代能源。因此，更多關於矽基太陽能電池生產的細節必須被開發研究。
本研究使用改良低成本創新的銀包銅金屬膏及兩階段高低溫燒結技術來完成正面電極的製作，目的為取代傳統正銀電極材料高成本以及含鉛玻璃的使用，並避免使用含鉛的玻璃，以開發出環保及低成本的「高導電率、高轉換效率、印刷式正銅電極」之太陽能電池應用。
在製程上使用抗反射膜(Anti Reflection Coating, ARC)薄膜沉積及背鋁印製之單晶矽太陽能電池基板，將自製的銀包銅粉體配製出高固含量的金屬導電膏，再利用綠光雷射(Green Laser)在抗反射層開槽孔形成H圖案，之後在矽基板進行網版印刷。在第一階段低溫燒結過程中，經由熱處理形成歐姆接觸，再利用高溫快速熱退火系統(Rapid Thermal Annealing, RTA)完成燒結。在燒結中，表面之奈米銀做為金屬銅粉與基板接觸的黏著劑，而銀包覆率大於90%的銅在燒結中能避免銅氧化得太嚴重，並可提升元件導電率。
各製程結束後分別透過四點探針、掃描式電子顯微鏡(SEM)、能量色散X射線光譜儀(EDS)、聚焦離子束(FIB)、穿透式電子顯微鏡(TEM)、傳輸線模型(Transmission Line Model，TLM) 及太陽光能量效率量測系統來分析材料電性、微結構、特徵接觸電阻及轉換效率。
本研究探討改良新型銀包銅金屬膏及燒結製程，可達成電阻率為6.70×10-6Ω-cm，既而傳統銀膏電阻率為4.83×10-6 Ω-cm，電性比較相差不遠，又可同時達成正面電極所需之歐姆接觸與較低之特徵接觸電阻，量測結果其特徵接觸電阻為0.0012Ωcm2，應用於太陽能電池轉換效率為18.13%，仍低於目前業界普遍所用的正銀電極材料。本研究之低成本改良新型銀包銅金屬膏搭配二階段燒結技術，成功開發出環保、低成本、低特徵接觸電阻、高轉換效率之矽基太陽能電池正面電極。

In this study, the use of improved low-cost innovative Cu core Ag shell metal paste and two-stage high and low temperature sintering technology to complete the production of positive electrode. The purpose is to replace the traditional high-cost silver electrode materials and the use of lead-containing glass, and to avoid the use of lead-containing glass. To develop environmentally friendly and low cost high conductivity of the positive electrode material.
In this study, a simple and effective method for the reduction and reduction was developed to synthesize experimental copper-coated copper powder with a coverage rate of over 90%. This not only prevented the oxidation of copper during the firing process, but also improved the conductivity. The And then through the paste technology will be made into the solar cell front electrode wire, and without losing the efficiency of its solar cells quality, expect to replace the relatively high price of traditional silver paste and the use of lead glass , To achieve cost savings and eco-friendly purposes.
In this study, we made a high solid content of silver-clad copper metal paste, not only can be printed in the 60μm narrow line, and has good rheology. Metal paste due to the organic solvent, glass, dispersant content ratio, solid content and the impact of three roller technology, and finally due to the different sintering temperature caused by the pros and cons of electrical properties. It is worth studying to explore these and final results. In the low-temperature sintering system process, these silver-coated copper paste sintered to 200 ℃ ~ 350 ℃, observed metal paste and silicon substrate contact, found in the low temperature sintering of organic solvents to volatilize, making the metal paste and silicon substrate more stable. So that the electrode of the solar cell element is peeled off from the silicon substrate at high temperatures.
Finally, we show that the silver-coated copper paste has a denser phenomenon at the sintering temperature of 300 ℃, and also has a low resistivity of 0.287 Ωcm2 at the temperature of the characteristic contact resistance.
Then, in the high-temperature sintering system process, the research data show that the lowest resistivity is 6.70×10-6Ωcm and the characteristic contact resistivity is 0.0012Ωcm2 when the one-stage low-temperature sintering 300 ℃ plus two-stage high temperature sintering 800 ℃. The resistivity of the silver-clad copper paste in our study is close to that of the conventional silver paste (≈4.83×10-6Ωcm). And the characteristic contact resistance is also close to the resistivity (≈0.001Ωcm2) of the conventional silver paste sintered in air. In spite of this, taking into account other factors, especially the stability of the back aluminum electrode and PN bonding, for low resistance and increased conductivity. Furthermore, it is proved that the density of the silver-coated copper paste is good after the high-temperature sintering and the contact between the front electrode and the silicon substrate is close, and then the ohmic contact is formed. Compared with the traditional silver paste not only cost reduction, and make the product more environmentally friendly.
In the study of the best parameter, the solar cell efficiency parameters are as follows. In the two temperature sintering process, Voc is about 0.60V, Isc is about 0.11A, the filling factor is about 32.15%, the efficiency is about 5.014%. With the high temperature sintering, Voc is about 0.62V, Isc is about 0.187A, the filling factor is about 73.93%, the efficiency is about 18.13%. The results show that our research on copper electrode technology is very successful.

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