覆晶球柵陣列構裝於可靠度彎曲測試下 之錫球裂縫長度與疲勞壽命關聯性研究

Correlation between the Solder Ball Crack Length and the Fatigue Life of FCBGA Components under the Cyclic Bend Test

王泰喬(Tai-Chiao Wang)

指導教授 ： 陳永樹

元智大學/工程學院/機械工程學系/碩士(2006年)

摘要

隨著高科技電子技術的進步，電子產品的功能愈趨複雜且尺寸更朝輕、薄、短小發展。而應用覆晶球柵陣列構裝(FCBGA)則為因應此趨勢而發展之IC構裝技術之一。然而電子產品難免因製造或使用時受到外力造成損壞，如何提高FCBGA元件的可靠度？為改善電子產品品質之重要關鍵因素。
本研究利用四點彎曲循環測試，對具有Daisy Chain之FCBGA元件進行可靠度實驗。並使用光學顯微鏡觀察其失效模式，配合有限元素模擬分析，由元件失效時之裂縫長度，再利用相關破壞理論探討與疲勞壽命、可靠度等之關連性。研究發現錫球裂縫發生之位置，會因錫球結構的差異而有所不同。而隨著裂縫產生處的差異，其應力強度因子(SIF)與裂縫長度即呈現不同的關係。因此，藉由Paris Law中裂縫長度與SIF的關係，建立了四點彎曲循環測試疲勞壽命預測模型，將可廣泛應用於電子元件之可靠度研究。

關鍵字

覆晶球柵陣列構裝 ； 錫球 ； 可靠度 ； 疲勞壽命 ； 裂縫長度

並列摘要

With the evolution of electronic technology, the electronic device becomes more complicate then ever before but with its size getting smaller and lighter. The development and application FCBGA component in the recent packaging industry is one of the measures to accommodate this trend. However, it is always inevitable that the electronic products will be subjected to some extent of external forces during manufacturing or customer use. To ensure the FCBGA components reliability becomes one of the crucial steps in improving the electronic products quality.

This study use four-point cyclic bend test to check the reliability of FCBGA components with built in daisy chain. The failure modes are also inspected with the optics microscope. It is then combined with the FEM analysis, the crack length at failure is related to the fatigue-life and reliability by way of the fracture mechanics theory. Experimental results reveal that the location of solder ball crack varies with different the solder ball construction. Also, the stress intensity factors (SIF) are then diverged with the crack location and crack length. Finally, a model to predict the FCBGA fatigue life under the cyclic bend test is presented by employing the Paris Law. It is believed that the model can be applied for further components reliability study.

並列關鍵字

Crack Length ； Fatigue Life ； FCBGA ； Reliability ； Solder Ball

參考文獻

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