David S. Knowles

P-59: Thin-beam Crystallization Method for Fabrication of LTPS

Thin film transistors fabricated using Low Temperature Polycrystalline Silicon (LTPS) have several well-known advantages over those made with amorphous Silicon: higher electron mobility, smaller size, higher speed. However, LTPS has not been widely adopted due to the relatively high cost and low yield of the process relative to a-Si. We have investigated a laser annealing process that offers an improvement for both throughput and yield when compared to existing processes. The process uses a very narrow laser beam (∼5 microns) at high repetition rates to create large poly-Si crystals via lateral growth. The beam length is long enough to allow the substrate to be scanned in a single pass, resulting in better uniformity without any seams seen in multi-pass techniques. In this presentation, we will present results from a prototype system used to validate the critical elements of the process.

P-60: Thin-beam Directional X'tallization Method for SOP and OLED Application

We propose a Thin-beam Directional X tallization (TDX) method, based on a high power, high repetition rate XeF excimer laser source and special optics, to produce a long, narrow (∼ 5 micron) beam with sharp edge slope. We present experimental results from a prototype TDX system that demonstrates very uniform directional laterally grown poly-Si films without any grain boundary protrusions.

Laser crystallization for flat panel display

We will review the status of current laser based crystallization processes, and discuss the specifications and the critical design aspects of the laser and of the optical system developed for the TCZ production tool.