SIX SIGMA CASE STUDY: BOND FINGER NODULE LRR IMPROVEMENT

六標準差案例研討：金手指凸起批退率改善

鍾慶達(Allen Chung) ； 何俊明(Jimmy Ho) ； 連志偉(Wallace Lien)

《品質學報》 23卷4期 (2016/08) Pp. 215-227

https://doi.org/10.6220/joq.2016.23(4).01

摘要

打線型封裝技術自1990年代即開始用來支援高腳數的產品設計，接合墊 (形似手指) 的品質將影響封裝良率。經過層別分析，「金手指凸起」為打線不良的首要缺點。為改善此問題，團隊參考了六標準差的分析方式來層別問題的原因，並透過一連串的實驗找出最適方案；改善成效顯著降低進料批退率，提升客戶滿意度的同時亦為內部相關品質成本節省了70.8%。

關鍵字

球形陣列 ； 打線基板 ； 批退率 ； 六標準差分析 ； 實驗設計

並列摘要

Since 1990's, ball grid array (BGA) assembly technology was developed by Motorola and Citezen to support high I/O count design requirement. IC substrate is a primary carrier and widely used by the BGA assembly technology. Bond Finger (BF) nodule defect contributes as top 1 defect of overall defects and caused customer high LRR (Lot Reject Rate) on wire bonding substrate. Hence, it is important to identify the root causes to reduce this failure. To improve this problem, Six Sigma Methodology is deployed on this project (Pande et al., 2002). Initial investigation indicates several factors in Ni plating process. By Cause & Effect Matrix and Pareto analysis, four factors are clarified as most possible root causes. To tackle this problem, DOE was conducted to find the optimized process control conditions. After improvement, the customer LRR reduce from 0.27% to 0.04% and 70.8% cost saving. It is encouraging to deploy the quality improvement with Six Sigma Methodology.

並列關鍵字

ball grid array (BGA) ； wire-bonding substrate ； lot reject rate (LRR) ； six sigma methodology ； design of experiments

參考文獻

Harman, G.(2010).Wire Bonding in Microelectronics.New York:McGraw-Hill.

Pande, P. S.,Neuman, R. P.,Cavanagh, R. R.(2002).The Six Sigma Way Team Fieldbook: An Implementation Guide for Process Improvement Teams.New York:McGraw-Hill.

(2005).PCB Trouble Shooting Guide.Taiwan Printed Circuit Association.