作為新一代矽薄膜太陽電池元件製作使用的透明導電氧化物(TCO)玻璃除了在透光率及導電性上有一定的需求外，對於光散射特性的提升特別是對近紅外光的有效散射能力為未來疊層型電池製作時不可或缺的要件。本論文中我們採用以噴塗球型氧化矽粉體於玻璃基材上來作為光散射層，考慮次微米級球型氧化矽粉體有著相當高的表面勢能，造成粒子間的互相凝聚使難達到良好的表面分散。因此如何製作一能有效降低球型氧化矽顆粒表面勢能來達到最適化的分散為本論文重要的課題。
本研究係以選擇適當原始粒徑的氧化矽球型粉體並以乙二醇為溶劑，混合後添加平均分子量為58000的聚乙烯吡咯烷酮（polyvinylpyrrolidone, PVP）作為表面活性劑，觀察並嘗試提高氧化矽粒子在該系統中的分散特性。
實驗結果顯示，以球型氧化矽粉體和適當分散劑混於有機溶劑中再以5000rpm高轉速的乳膠均質機結合超音波震盪器持續進行24小時候，可以有效提升氧化矽粒子間的凝聚作用。接著將調製好的粒子溶膠(gel)以旋轉塗佈法製作散射層並由SEM與UV/VIS量測觀察氧化矽散射層的表面粒子狀態與光學特性。結果發現以原始粒徑為0.25m的氧化矽粉末經適當分散塗佈於玻璃基材上時，可形成均勻粒子分散層(最大粒徑不超過2m)。再經固定化之後可獲得穿透度超過90%並且在700~1200 nm長波長光範圍有大於25%的散射穿透率特性。

Light trapping technique is of great importance in increasing the conversion efficiency of thin film silicon solar cells, through minimizing optical reflection and thus increasing the light adsorption in the active layer region. Light trapping is strongly influenced by the surface roughness of transparent conductive oxide layer. One of the efforts to achieve this purpose is using amorphous silica balls as the scattering objects, and dispersing these silica balls on the surface of glass substrates. However, submicron silica particles, with high surface energy, tend to aggregate with each other and therefore cause poor dispersion capacity. Modification of colloidal silica surface is necessary to achieve optimum stability so that they could be dispersed well to form an ideal scattering layer on TCO glasses.
Here, in this thesis, surface modification using nonionic polyvinyl pyrrolidone, with an average molecular weight 58,000, as a surfactant was chosen. The effect of dispersion was also compared with the case when cetyltrimethylammonium bromide was applied as an ionic stabilizer.
A good mixture between colloidal silica in an organic solvent and a stabilizer was needed to achieve well-dispersed and stabilized silica particle emulsion. In addition, high speed of the emulsion homogenizer, as high as 5000 rpm, combined with ultrasonic vibration was applied for 24 hours to break the interaction between particles and give stable colloidal silica. Then, spin coating with 3000 rpm for 20 seconds in the first step and 4000 rpm for 30 seconds in the second step was performed to deposit modified silica particles on the glass substrates. The dispersion of the light scattering layer was investigated by scanning electron microscopy (SEM) and its optical properties were evaluated using UV/VIS spectrometer with an integral sphere.

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