Low-Temperature Fabrication and Characteristics of Lanthanum Indium Zinc Oxide Thin-Film Transistors

We fabricated lanthanum indium zinc oxide (IZO) (La-IZO) thin-film transistors (TFTs) using radio frequency cosputtering of IZO and lanthanum. The field-effect mobility and switching ratio of the La-IZO TFTs were 4.2 cm
²
·V
^-1
·s
^-1
and on the order of 10
⁸
, respectively, before thermal annealing and 3.02 cm
²
·V
^-1
·s
^-1
and on the order of 10
¹⁰
, respectively, after thermal annealing at 150
^°
C in air. Our La-IZO TFTs had better thermal stability than pure-IZO TFTs due to the stable ionic bond between La and O.