Ultrathin Mg0.05Sn0.95Ox-Based Thin-Film Transistor by Mist Chemical Vapor Deposition

The 5-nm-thick Mg
_0.05
Sn
_0.95
O
_x
thin film deposited using mist chemical vapor deposition is used as a channel layer of the thin-film transistor (TFT). Mg
_0.05
Sn
_0.95
O
_x
improves the crystallinity, reduces the number of oxygen deficiencies, and enlarges the energy bandgap compared with SnO
₂
. Mg
_0.05
Sn
_0.95
O
_x
-based TFT shows higher field-effect mobility (144.9 cm
²
V
^-1
s
^-1
), steeper subthreshold slope (134 mV/decade), and significant ON/OFF current ratio (>10
⁹
) than the SnO
₂
-based TFT. Owing to fewer oxygen-related defects, wide energy bandgaps, and stable Mg-O chemical bonding, the Mg
_0.05
Sn
_0.95
O
_x
-based TFT exhibits more stable electrical performance than the SnO
₂
TFT after negative bias illumination stress testing. These results suggest that Mg
_0.05
Sn
_0.95
O
_x
is a promising material for high electron mobility TFT applications.