軟性顯示面板缺陷改善

Abstract

在本篇論文中主要的研究是應用品質工具改善軟性顯示面板製作流程中的潛在失效問題，本研究為軟性顯示面板之開發導入品質改善手法，以達成節能、多色產品應用之實現[1]。在品質分析及改善方面，利用失效模式與效應分析(Failure Mode and Effect Analysis, FMEA)與要因分析手法、田口法、福特8D法（F8D），系統性地找出失效矯正措施，有效地改善品質產出，並搭配製程規範及半成品產出檢測規範之訂定，使面板產出良率大幅提升，將製程良率由65%提升至90%以上。 軟性顯示技術的單基板結構不但可使顯示器更輕更薄且更軟，亦可因結構簡化而降低成本且提升良率，也可因其微胞間隙(Cell Gap)的穩定而使所顯示的影像不因壓力而改變；液晶雙穩態的特性可在無供電的狀況下維持影像，只有在更新影像時才要供電，因此具有省電與環保的優勢，其省電特性亦可減少所需電池的重量，顯示器的可攜性可再提升；液晶微胞化後，將大幅增加本顯示技術的耐衝擊性；本技術的顯示器結構與影像驅動皆為被動矩陣式，因此無需昂貴的主動式電晶體背板（Backplane）；而本技術是以膽固醇液晶(Ch-LC)來反射光線，並以液晶的微胞高度(Pitch)來決定反射的顏色，因此無需偏光片、背光源、彩色濾光片。所以「軟性顯示技術」不但擁有更輕、更薄、更軟，亦具有生產快速、成本低、省電、影像不隨壓力改變、以及耐衝擊等優點[1,2]。

To improve the potential failure issues which are in the flexible display process flow is this research target. We used the quality improvement tools to solve the issues and improve the saved energy and got more color in the flexible display[1]. We improved the quality that is used four tools which are the Failure Mode and Effect Analysis (FMEA), Root Cause Analysis, Taguchi Methods and Ford 8D (F8D) to find the measures of the failure issues in systematically. We set up the process specifications and semi-product testing standards to improve the process yield from 60% to more 90%. The flexible display is the single cell structure and the display will be more light, thin and flexible. Because the flexible display is simple structure, the cost will be down and yield will be high. Another, the cell gap is more stability and the display quality will not be changed by pressure. Bistable liquid crystal can keep the image in the display and it doesn’t turn on the power. When it change the image, it will be turned on the power. So bistable liquid crystal display has the excellent saved power and environmental protection. It will reduce the weight of battery and make the display more portable. When we reduce the liquid crystal cell to be micro structure, the display will be more anti-pressure. We chose the passive matrix structure to make this display and drive the image. We don’t need the expensive active backplane. We chose the cholesteric liquid crystal (Ch-LC) to reflect light and control the liquid crystal pitch to determine the reflection color without the polarizer, backlight and color filter. The flexible Ch-LC display has many advantages which are light, thin, flexible, throughput quickly, low cost, saved power, kept image even in pressure and anti-pressure[1,2].