Performance Enhancement of Self-Aligned Coplanar TFTs With ALD-IGZO Channels via Effective Doping From Interlayer Dielectric

A doping technique to form the conductive source/drain regions of self-aligned coplanar thin-film transistors (TFTs) employing In-Ga-Zn-O (IGZO) channels prepared by atomic-layer deposition was uniquely demonstrated. The electrical resistivity of the IGZO film was reduced to
${2}.{88}\times {10} ^{-{4}}\,\,\Omega \cdot $
cm after simple Al
₂
O
₃
interlayer dielectric deposition process using
$\text{H}_{{2}}\text{O}$
. The field-effective mobility of the fabricated IGZO TFTs was 23.4 cm
²
/V.s and trustworthy device stabilities were confirmed. Furthermore, small values of the channel width-normalized contact resistance could be obtained to be as low as
$8.5~\Omega \cdot $
cm.