Chapter 1 Introduction

Abstract

Polysilicon TFT is the key building block for active matrix liquid crystal display (AMLCD) and active matrix organic light emitting diode (AMOLED) due to its faster switching characteristics and high driving current. Its fabrication is similar to the conventional MOSFET process flow and the most difference is the processing temperature. The maximum temperature limited in MOSFETs is about the silicon melting-point, and the temperature in polysilicon TFT fabrication should be less than 600-650 C, due to the commercial considerations that we can processing all fabrications on the cheaper substrate materials such as the glass or the plastic. Low-temperature-polysilicon technology is developed for this reason.