■ Title : Low Temperature Crystallization of Si films for TFTs by Laser Annealing on Panels
■ Speaker : Takashi NOGUCHI (University of the Ryukyus)
■ Date and time : 24th of November, 2017 (Fri) 14:00
■ Venue : Applied Engineering Dpt. Bd W1-1 Room 1318
■ Host : Prof. Sang-Hee Park
■ Abstract : Laser Crystallizations using Blue Laser-Diodes Annealing (BLDA) as well as conventional Excimer Laser Annealing (ELA) are presented for mounting the TFTs on panels. On glass, high crystallinity of Si films can be obtained by using multi-shots ELA as well as CW laser scanning. In term of lower temperature TFT process on flexible plastic sheets, pulsed ELA of UV light is faborable. However, there are some issues after ELA. As a result of BLDA scanning for thin Si films, remarkable crystallization occurs with keeping the surface smooth not only for CVD film but also for sputtered Si film . By changing the laser power of 445 nm beam, the grain size can be controlled from micro-grains to large grains as well as to anisotropic long crystal grains. For the Si films of heavily phosphorus doped condition, the resistivity decreased drastically after BLDA as well as after multi-shots ELA. In order to perform low temperature TFT process, metal source/drain (S/D)structure without using impurity doping is proposed for TFTs with low fabrication cost on panel.