- 學位論文
超音波噴塗磷酸/硼酸與圖形化摻雜應用於交指狀背電極太陽能電池
Locally Patterned N+ and P+ Doped Layers for Interdigitated-Back-Contact Solar Cells by Ultrasonic Spray Technique
摘要
n型與p型矽摻雜在太陽能電池領域以及IC產業中都有非常重要的應用，在工業中最被廣為應用的摻雜方法為離子佈植以及熱擴散。但這兩種製程方式都必須使用到精密的真空設備，且若要圖形化摻雜均須使用黃光微影而使得成本昂貴，甚至在硼和磷擴散最常所使用的擴散源BBr3、BCl3和POCl3均是具有強烈臭味的有毒物，不僅對操作人員危險，甚至對環境也有害。 本研究以超音波震盪噴塗磷酸和硼酸於矽基板表面製作p型與n行之圖形化摻雜，並應用於交指狀背電極太陽能電池。除了製程無毒、無害之外，以此方式能以簡單的設備在大氣下進行鍍膜，並且不須經過昂貴且繁複的黃光製程即可輕易將定義出的區域做圖形化的摻雜，甚至可在單面基板上同時噴塗出p型和p型的圖案，並只須在空氣中進行單次退火便能直接得到p型與n型的摻雜區域，對於高效率矽晶電池中的交指狀背電極太陽電池(Interdigitated-Back-Contact Solar Cells)有良好的應用性。 另外，本研究在p型和n型摻雜濃度上也可以做到有效的控制，依照硼酸/磷酸的濃度、噴塗時間、硼/磷玻璃厚度和退火溫度即可調整片電阻值。已知道摻雜濃度越高則基板表面片電阻越低，本研究可藉由控制硼或磷的摻雜狀況而逐漸降低片電阻，n型摻雜可由原始片電阻約125Ω/□逐步控制到重摻雜的28Ω/□；p型摻雜則可由原始片電阻約125Ω/□逐步控制到重摻雜的30Ω/□。
並列摘要
Abstract Phosphoric acid and boric acid were used as low cost, nontoxic n-type and p-type doping sources for silicon solar cells. In this research, we coated dilute phosphoric acid and boric acid on silicon wafer by ultrasonic spray coating method without any additional complicated vacuum system. Furthermore, a designed pattern diffusion area can be obtained by using an easily removed mask. After these two acids spraying on, the n-type and p-type patterned area can be driven-in at just one annealing process in air. The sheet resistance of the n-type and p-type doping area can be controlled by spraying time and annealing temperature. In phosphorus doping, sheet resistance ranging from 28 to 125Ω/□ were achieved. In boron doping, sheet resistance from 30 to 125Ω/□ could be acquired. The n-type and p-type doping fabrication process by low cost ultrasonic spray method can be used for Interdigitated-Back-Contact (IBC) solar cells application.