請用此 Handle URI 來引用此文件:
http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/79016
標題: | 切割矽泥回收製作可重複使用的坩堝在多晶矽生長之研究 Multi-crystalline Silicon Growth by Reusable Crucible Made from Recycled Kerf-loss Silicon |
作者: | I-Tseng Liu 劉以增 |
指導教授: | 藍崇文 |
關鍵字: | 鑽石線切割,切割損失,矽回收,氮化矽,可重複使用,氮化程度,氮化矽裂解, Diamond-wire slicing,Kerf-loss,Silicon recycle,Silicon nitride,Reusable,Degree of nitridation,Decomposition of silicon nitride, |
出版年 : | 2017 |
學位: | 碩士 |
摘要: | 隨著太陽光電產業快速發展,2017年產出超過90 GW,其中矽晶電池就超過92%。製造矽晶碇過程中,鑄碇過的石英坩堝與矽晶圓切割損失矽泥是太陽能產業兩大廢棄物。近年來,在晶圓切割製程上幾乎完全被鑽石線切割製程取代,使得切削的矽泥損失減少至40%,然而仍是大量的耗損。
因此吾人嘗試落實循環經濟、循環材料及永續發展的概念並建立可以處理上述問題的製程,透過使用回收矽粉製成氮化矽坩堝,達到純度比目前商用的石英坩堝更為高,與純氮化矽相比燒結時的形變率更低,坩堝在每次重複使用時雜質會被矽錠帶走,會越用越純,進而提高矽錠的品質以及太陽電池的效率。並同時解決廢棄石英坩堝的問題。 與一般文獻不同之處在於吾人使用回收矽而非一般商用矽粉且不須額外添加氮化矽粉,做為製作坩堝的起始原料。切割損失矽泥經過酸洗製程去除金屬與硼磷後,利用注漿成型方法做出坩堝生坯,並於常溫下於空氣流動的環境風乾。風乾的坯體經過3小時500℃高溫熱處理,去除矽泥中的切割冷卻劑及潤滑劑等高分子添加劑與基板中的樹酯後,透過控制升溫速率與持溫溫度在氮氣與氫氣(5 vol%)的氣氛下進行氮化,製作成RBSN (Reaction-Bonded Silicon Nitride)坩堝。 在長晶時使用氬氣與氮氣的(5vol%)氣氛中,可有效的避免氮化矽於高溫下低氮氣分壓下的裂解現象,並減緩結構弱化與剝落的問題。另外,吾人比較傳統氮化矽塗佈層的影響與坩堝初始純度對於長晶的影響以提高重複使用的次數與減少紅區。 As the rapid development in PV industry, more than 90GW production, which consist of more than 92% silicon-based solar cell, was reached in 2017. Nevertheless, two major wastes, that is, kerf-loss silicon and broken quartz crucibles for casting, are produced. Nowadays, procedure for wafer slicing is almost replaced by diamond wire slicing. Even through, 40 wt.% of weight loss is unavoidable. We try to imply the concept of circular economy and circular material by proposing and presenting procedures for solving problems mention above via converting recycling kerf-loss silicon into silicon nitride crucibles, which can not only lower linear shrinkage than silicon nitride sintering but also become purer after every crystal growth. We can obtain higher ingot quality at initial crystal growth and therefore higher efficiency for solar cell. We do believe our idea and design can turn a new leaf in PV industry. Compare to literatures, we recycling kerf-loss silicon are purified by acid to remove metals, boron and phosphorus. After that, slip casting is applied for crucible manufacturing and drying under room temperature. Green body undergoes heat pre-treatment at 500℃ for 3 hr to remove polymer from coolant and lubricant in slicing procedure and also resin from substracts. Nitridation is followed. We control heating rate and holding temperature during nitridating and under atmosphere of N2 mixed with 5 wt.% H2. 5 wt.% N2 is added in Ar to avoid decomposition of silicon nitride during crystal growth. Also we present the effect of commercial silicon nitride coating and the effect of crucible purity to enhance the reusability of crucible. |
URI: | http://tdr.lib.ntu.edu.tw/jspui/handle/123456789/79016 |
DOI: | 10.6342/NTU201803321 |
全文授權: | 有償授權 |
電子全文公開日期: | 2023-08-19 |
顯示於系所單位: | 化學工程學系 |
文件中的檔案:
檔案 | 大小 | 格式 | |
---|---|---|---|
ntu-106-R05524066-1.pdf 目前未授權公開取用 | 5.16 MB | Adobe PDF |
系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。