High-Quality $\hbox{MgO}/\hbox{TiO}_{2}/\hbox{MgO}$ Nanolaminates on p-GaN MOS Capacitor

In this letter, the electrical characteristics of nanolaminate MgO/TiO
₂
/MgO on a p-GaN MOS capacitor with and without postmetallization annealing (PMA) and (NH
₄
)
₂
S
_x
, treatments are investigated. With both PMA and (NH
₄
)
₂
S
_x
, treatments, the leakage current densities are reduced to 3.9 × 10
^-8
and 3.7 × 10
^-8
A/cm
²
at ±1 V, respectively. With a much-improved C-V curve, the effective dielectric constant of the gate dielectric stack for both treatments is 17.8, and an averaged interface trap density of 3.1 × 10
¹¹
eV
^-1
cm
^-2
is obtained.