銀膠在矽太陽能電池的大規模生產中發揮重大作用，故本研究藉由實驗成果得知：製備銀膠，銀粉為80 wt%~85 wt%，且粒徑為1~1.5 μm之圓球狀有較佳的成型性。隨著溫度的提高對於銀有成長的趨勢。在燒結860℃，持溫時間為10分鐘有最低片電阻4 mΩ/sq。由SEM發現銀膠燒結以氧化銀的方式固融在玻璃裏，最後銀會結晶為核狀而成長在玻璃層。矽基板因為受到玻璃及銀的氧化還原影響，藉由SEM之EDS和TEM證明介面上會生成二氧化矽(50 nm~75 nm)。經腐蝕可觀察到 (1)結晶銀直接與銀層連接 (2)結晶銀在玻璃內 (3)玻璃層 (4)圓球狀奈米銀在玻璃層內，因此提出銀膠在矽晶圓燒結後的模型趨勢。最低接觸電阻值在830℃為1.92x10-4 (Ωcm2) 而最高890℃為6.3x10-4 (Ωcm2)，而各別單一結晶銀的接觸電阻值為2.9x10-8(Ωcm2) 和2.2x10-7(Ωcm2)。隨著溫度的提高，結晶銀過度成長造成漏電流發生。玻璃粉粒徑大於銀，燒結容易膨脹反之則收縮。玻璃軟化點及添加量影響著介面玻璃層，經由不同的玻璃轉移溫度對於銀膠之影響，整理得知: (1)具備氧化還原氮化矽層 (2)控制銀再結晶之顆粒大小 (3)銀溶解在玻璃層的多寡。藉由TEM證實燒結溫度將使結晶銀伴隨著玻璃內析出，玻璃層將視添加比例不同而有連續性得分佈在介面上，所以本實驗得知，燒結溫度對於玻璃粉的影響有: (1)氧化還原氮化矽層的速度 (2)銀與矽介面玻璃層之厚度。由EDS及SIMS量測玻璃層在830℃~890℃的範圍為2~4 μm，而最薄為0.2~0.8 μm。由於結晶銀在介面處會生成氧化層，銀原子會擴散反應可達3 μm，其反應活化能為35 kJ/mole，其擴散趨勢符合一般擴散現象。

Since the silver paste plays a major role in the mass production of silicon solar cells, this research has studied its physical characteristics. This research has succeeded in optimizing the silver paste in 80 wt%~85 wt% and controlling its particle size in 1~1.5 μm spherical powder. As the firing temperature is increased, the growth trend of silver grain is improved. The result has showed that the lowest sheet resistance is 4 mΩ/sq during the 860°C sintering process. The SEM observation has showed that the formation of silver oxide is formed during the melting process of glass and triggered redox reaction of Ag crystallites to grow on the interface. It has proven that a thin layer of silicon oxide (50 nm~75 nm) was formed. The separate layer in the interface was determined successfully as: (1) Ag crystallites direct contact with silver layer (2) Ag crystallites in glass layer (3) glass layer (4) spherical nano silver particle in the glass layer; therefore the research has proposed a new model of silver and silicon interface. The special contact resistance is the lowest value of 1.92x10-4 (Ωcm2) in 830℃ and the highest value of 6.3x10-4 (Ωcm2) in 890℃; As to the single Ag crystallites is the lowest value of 2.9x10-8 (Ωcm2) and the highest value of 2.2x10-7 (Ωcm2). This research has concluded that the increase of the firing temperature will cause the excessive growth of Ag crystallites and also cause leakage current to occur. This research has also concluded that he glass transition temperature and glass additive play an important role in contact surfaces between the silicon and silver in the experiment. The difference of glass transition temperature used in the silver paste has confirmed: (1) the ability of redox reaction of silicon nitride layer (2) the control of Ag recrytallites size and (3) the solubility amount of silver in glass. The TEM results has also confirmed that the precipitation of Ag recystallites is followed from the interface glass layer, and the continuous of interface glass layer is controlled by the amount of glass addition. By means of EDS and SIMS, the measurement of the glass layer are 2~4 μm in thickness and 0.2~0.8 μm in the thinness. Due to the Ag crystallites, the formation of oxide layer occurs which is caused by the Ag diffusion. The experiment has detected 3μm length of diffusion and the activation energy is 35 kJ/mole in the general diffusive tendency. Finally, the research has also concluded that two facts of glass addition when sintering: (1) the speed of redox reaction of silicon nitride layer and (2) the thickness of glass between silver and silicon.

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