應用六標準差方法提升半導體封裝製程品質

Abstract

在21世紀高科技產業在世界舞台的兢技場上，除了新產品推出市場的速度要快外，高品質與低成本定更是在市場競爭中勝出的重要關鍵。以產品品質來說，基本上由於高科技產品的相對價值較高，大部份的廠商都是以最佳化的整合模式，投入其設計、原料、機器設備、製程、生產系統及人力資源以保證出貨的品質在一定的水準之上，同時也滿足客戶的基本需求。由其面對微利時代的來臨，如何“同中求異”、超越競爭對手並擴大市場佔有率，創造品質的差異性甚至達到品質零缺點，更是一線廠商努力的標的 不論任何產業，持續品質改善已經是在整個生產活動中不可或缺的一環。解決問題的方法有很多，最重要的是有決心，能在不同的時機選擇最適當的工具，以有效的解決核心問題。本論文是應用六標準差方法來解決封裝的品質問題。有別於其他方法，它不僅是個高度整合、具有詳細問題解決的步驟及同時經過國際大廠(MOTOROLA和GE等)的實証，而且也是一個著重於文化的改變、教育的深耕、以探討核心問題並量化有效產出的方法。 本文的另一個特色是建立品質領先指標。我們都清楚“預防重於治療”，即品質是靠設計出未來的，而不能僅靠製造或是檢驗。但是世界上也沒有一個東西是恆久不變，或者只是你沒發現而已。所以面對製程本身存在的變異，重點是控制合理變異和偵測異常變異，否則除了其所衍生的重工成本和客戶退貨處理成本外，最重要的是影嚮企業高品質的形象。因此如何有效的偵測與客戶應用相關的關鍵製程異常，在其尚未對產品出貨品質造成危害前加以控制與改善，是品質管制中一個相當重要的觀念與方法。

As organizations are facing increasing global competitiveness and more stringent requirements on products and services that result in trend of micro profit, greater attention is given to manage and improve quality, cost and speed. Many Manufacturing companies operate around four sigma or 6,200 DPMO (defects per million opportunities). Nowadays, fierce quality requirements from the Customers have caused IC manufacturers to seek more efficient quality improvement methods to produce defect free products. Unfortunately, some non-conformance failures could not be detected neither by in-process monitor nor final functional test until those devices are placed onto modules at customer’s sites. Consequently, customer will suffer enormous loss regarding to call back all suspected products from the market. That is the reason why some IC manufacturing companies now turn their metrics from parts per million (PPM) to parts per billion (PPB). Many industry practitioners have been trying hard to set up many quality improvement approaches such as QCC, SPC, TQM, and ISO9000 during the past decades. However, those methods have some limitations in practice resulting in inefficient attempts to understand and achieve the ultimate goal in terms of defect free products. Recently, the implementation of Six Sigma to improve Customer satisfaction and reduce variability in performance has gained more and more attentions among all industries. Six Sigma is revealing a potential for success that goes beyond the levels of improvement achieved through the many other quality improvements efforts. This thesis aims to achieve two goals for the ICs assembly process: (1) to apply the Six Sigma approach to improve quality, and (2) to create the leading index for specific quality characteristic. Therefore, a proposed Six Sigma approach is described in this chapter to solve the mentioned intentions. The proposed procedure has applied to a semiconductor factory to demonstrate the practicability of the methodology.