Interfacial Reactions Between Copper Plated Materials and Solders (SAC105, LF35)

數十年來，鉛對於環保的衝擊頻頻遭受質疑。環保專家不斷警告此金屬對於人體健康的影響，因此在70及80年代，美國及其他許多國家的建築法規早已規定不得使用含鉛塗料。但是電子產品廢棄物數量的快速增加，卻帶給此議題新的急迫性。為回應這個日益嚴重的環保問題，歐盟於2003年公布禁用危險物質(RoHS)指令，於2006年7月生效，RoHS禁止使用含鉛、汞及鎘的電子銲料所製造的電子產品銷往歐洲市場。由於鉛具有絕佳的電子及機械特性，長期廣泛用於半導體封裝及電路板上。但是鉛對於環境的衝擊飽受質疑，加上歐盟更已公布RoHS指令，禁用含鉛、汞及鎘的電子銲料。這些新規定使得半導體產業必須先克服調高回流焊接溫度所衍生的問題。由於無鉛銲錫的熔點較高，因此採用新銲錫的元件必須承受較高溫度，同時仍須確保產品壽命及可靠度。 本研究是使用兩種不同銲料(SAC105、LF35)與電鍍銅基材進行界面反應的探討。在固定反應溫度260 ℃下，進行30 s的迴銲反應時間，再放入烘箱進行不同溫度(150 ℃ & 200 ℃)與不同反應時間(24 h、72 h、144 h、600 h、1000 h) ，進而了解錫球與電鍍銅基板之間的機械強度比較。In the past decades, lead (Pb) has been questioned about its impact on the issues of environmental protection. Environmental experts continue to warn that Pb has harmful effects on human health. So, in the 70s and 80s, the United States and many other countries have legislated against the use of Pb paint in the building regulations. However, the rapid increase in the number of electronic waste products brings new urgent issue in the Pb usage. In response to this increasingly serious environmental problem, the European Union in 2003 announced the Restriction of Hazardous Substances (RoHS) directive. The RoHS became effective in July 2006, and since then the use of lead, mercury, and cadmium in the electronic products sold to the European market was prohibited. Lead has excellent electronic and mechanical properties, so it has been long-term widely used in semiconductor packaging and circuit boards. However, the impact of lead on the environment is questioned, coupled with the RoHS directive that banned lead, mercury and cadmium in the manufacturing of the electronic products. These new regulations push the semiconductor industry to overcome the problem caused by the increase of the reflow soldering temperature. Due to the high melting point of lead-free solder, the use of new solder components must withstand higher temperatures, while still ensuring product life and reliability. This study investigates the interfacial reactions of two different solders (SAC105 and LF35) with electroplated copper substrates. The experiment runs with 30 seconds reflow time under the constant temperature of 260 ℃ and the samples are placed into an oven at different temperatures (150 ℃ and 200 ℃) for different reaction times (24 h, 72 h, 144 h, 600 h, 1000 h). The mechanical strength of the solder/Cu samples is also investigated and compared.目錄 誌謝 i 摘要 iii Abstract iv 目錄 vi 圖目錄 viii 表目錄 x 第一章 緒論 1 1. 前言 1 第二章 文獻回顧 3 2.1 電鍍銅技術的發展 3 2.2 電鍍銅添加劑 5 2.2.1 電鍍銅抑制劑 6 2.2.2 電鍍銅加速劑 6 2.3 銲料與介金屬化合物 7 2.4界面反應 9 2.5 推球實驗測試機制 10 第三章 實驗方法與設備 13 3.1 材料的製備 13 3.1.1電鍍銅基材製備(PC & PCS) 13 3.1.1.1電鍍銅基材製備(PC) 13 3.1.1.2電鍍銅基材製備(PCS) 17 3.1.2 銲料 17 3.1.2.1 液固迴銲反應(Liquid-Solid Reflow Reaction) 19 3.1.2.2 固固反應(Solid -Solid Reaction) 19 3.2 金相界面觀察與分析 20 3.2.1 研磨拋光與冷鑲埋 20 3.2.1.1 冷鑲埋 20 3.2.1.2 研磨拋光 21 3.3 錫銅接點機械強度測試 22 3.3.1 推球實驗測試 22 第四章 實驗結果與討論 25 4.1 SAC105、LF35與電鍍銅基材之界面反應 25 4.1.1 添加劑對電鍍銅性質影響 25 4.1.2 Sn/Cu接點界面反應與機械強度的影響 35 第五章 結論與未來展望 45 5.1 結論 45 5.2 未來展望 47 參考文獻 4