The Characteristics of Single-Pulse Excimer Laser Beam Profile on the Low Temperature Poly-Si TFTs
Abstract
Laser crystallization has been the most promising technology to manufacture low temperature poly-silicon (LTPS) thin film transistors (TFTs), since LTPS technology can make LCD panels with integrated drivers. Higher mobility and lower leakage current than the solid-phase crystallization (SPC) counterparts can be obtained by laser crystallization. I excimer lasers emit in the UV region with a short pulse duration (lO^3Ons), and high temperature can be developed in the Si-surface region, causing melting, without appreciative heating (4OO degrees C) with the glass substrate. 2 Laser processes should provide uniform and stable laser beam profiles to obtain uniform distribution of electrical characteristics of TFTs. In this study, the effects of laser beam profiles were investigated on the crystallization of poly-Si films. "One Pulse" laser crystallized poly-Si was analyzed by SEM and alpha-step to distinguish the effects of non-uniform laser beam profiles. Surface smoothness of poly-Si films with various laser-overlapping ratios was also measured to investigate the effects of laser beam profiles. Then the relationships of TFT characteristics and laser overlapping ratios will be discussed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2000
- Accession Number
- ADP011301
Entities
People
- Chu-jung Shih
- I-min Lu
- I-wei Wu
- Li-ming Wang
- Shih-chang Chang