本研究旨在探討晶圓級晶片尺寸封裝產品錫球氧化的改善，由於此封裝結構會透過錫球與印刷電路板進行焊接，若產品摔落或遭受外力撞擊，容易發生焊接點斷裂，其中影響焊接強度的主要因素是焊接後所生成的介面合金共化物的強度，因此避免氧化影響焊接的品質，為本研究的目的。藉由使用8D問題解決法，系統化地進行分析並找出發生的真因進而改善。研究中先針對之前的失效模式與影響分析進行確認，在分析問題的過程中使用光學顯微鏡、能量色散X射線光譜、傅立葉轉換紅外光譜做為檢測工具，並於實驗中加入類似潮濕敏感測試等級1的溫溼度試驗條件85℃及 85%相對溼度進行加速實驗，找出助焊劑殘留的原因與氧化發生的機制以及助焊劑清洗的氮氣時間設定，依本研究的結論提出相關的解決方法。

This paper investigates the improvement of solder ball oxidation in wafer-level chip-scale packaging products. Since this packaging structure involves soldering solder balls to a printed circuit board, the solder joints are prone to breaking if the product is dropped or subjected to external impact. The primary factor influencing solder joint strength is the strength of the intermetallic compounds formed after soldering. Therefore, preventing oxidation from affecting soldering quality is the goal of this research. Using the 8D problem-solving method, a systematic analysis was conducted to identify the root cause and implement improvements. The study first confirmed previous failure modes and effects analysis. During the problem analysis process, optical microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy were used as inspection tools. Additionally, accelerated tests were conducted under temperature and humidity conditions similar to Moisture Sensitivity Level 1 testing at 85°C and 85% relative humidity to identify the causes of flux residue, the oxidation mechanism, and the nitrogen time setting for flux cleaning. Solutions based on the study's conclusions were proposed.

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