42.3: 4‐in. VGA Reflection‐Type Poly‐Si TFT LCD with Integrated Digital Driver Using Seven‐Mask CG Silicon CMOS Process

Abstract

A reflection type poly-Si TFT LCD having integrated digital driver comprising CMOS structure has been fabricated with 7 masks by using the CG Silicon technology in order to prove low cost production. The details of a novel circuit structure and CG Silicon process, adopted here, will be mainly described.

A five mask CMOS LTPS process with LDD and only one ion implantation step

“…Also, there are some proposed OLED-pixel circuits which require both NMOS and PMOS TFTs. Usually seven or more photolithographic steps are required for the production of CMOS circuitry with lightly doped drain (LDD) structures [2]. One mask step can be saved if no LDD is implemented, but leakage current of n-channel TFTs is then increased [3].…”

Alternating magnetic field-assisted crystallization of Si films without metal catalyst

“…Modified SPC techniques, such as including metal-induced crystallization (MIC), metal-induced lateral crystallization (MILC) and electric field-enhanced crystallization (EFEC), have been also proposed in order to reduce the process temperature and time by adding catalytic metals such as Ni to the pre-cursor a-Si films or applying the electric field [9][10][11]. However, this causes the problem of large dispersion of OFF current in TFT operation by undesirable metal contamination in the poly-Si films [12].…”