Low temperature polysilicon chemical vapor deposition system for thin filmtransistor liquid crystal diode

Polysilicon thin film transistor (TFT)-based displays are increasingly foun d in cell phones, mobile communicators, PDAs, portable DVD players, and mob ile computers because they have high resolution and low power consumption. The AKT plasma-enhanced chemical vapor deposition system made by Applied Ma terials is used to deposit multilayer dielectric films including precursor low-hydrogen-content amorphous silicon for manufacturing these displays. Th e polysilicon film is converted from an amorphous precursor film by an exci mer laser annealing process. Production of a good quality polysilicon precu rsor film requires that the hydrogen content of the film be controlled belo w 2%. Achieving low hydrogen content requires uniform treatment at high tem perature (500 +/- 10 degreesC) after deposition. This article describes the design and performance of the large, high temperature heat chamber integra ted in a cluster-tool-based deposition system for both preheat and postanne aling of the substrate. [Q. Shang, T. K. Kardokus, and A. Hosokawa, U.S. pa tent pending (Dec. 2000).] (C) 2001 American Vacuum Society.