Analyzing Foreign Matter in the Glass Substrate for Liquid Crystal Displays

Introduction

In recent years, liquid crystal displays have become ubiquitous in the world in which we live; they provide the screens for our televisions, cell phones, PC monitors, and so on. Active matrix liquid crystal displays (AM-LCD), which operate using thin-film transistors (TFT) mounted on a glass substrate, are capable of displaying truly beautiful images. Such AM-LCDs, in order to retain the thin-film functionality, demand that certain high-level characteristics be maintained. For example, the glass needs to be free of alkaline substances (they can lead to a degradation of the transistor properties by diffusing within the liquid crystal). The glass also needs to be heat-resistant (even at a thickness of approx. 0.7 mm, thermal contraction during the manufacturing process must be kept to a minimum), and it needs to be resistant to chemicals (such as component elution from chemical treatments during the manufacturing process). We here introduce an example of the analysis of a TFT glass substrate using EPMA.

September 26, 2014 GMT