P‐29: A Novel Six‐Mask Process for High Performance μc‐Si TFT Using Indirect Thermal Crystallization

Abstract

In this work, we have fabricated high performance μ c-Si TFT using bottom gate 6-mask process. IR laser diode was used for crystallization of a-Si films. The gate pad (Mo) for TFT and gate bus line (Cu) were formed simultaneously by half tone mask technique. To solve the problem that the gate metal is damaged by heat during the laser thermal crystallization, Mo heat transition layer which acts as an IR absorption layer was patterned and the high reflective property of Cu within IR wavelength was also based on. Selective crystallization of a-Si for gate damage free is absolutely needed in this work. We achieved high and stable device characteristics of which the mobility was more than 6.2cm 2 /V·s through this technique.