Electrical Characteristics of $\hbox{Al}_{2} \hbox{O}_{3}/\hbox{TiO}_{2}/\hbox{Al}_{2}\hbox{O}_{3}$ Nanolaminate MOS Capacitor on $p$-GaN With Post Metallization Annealing and $(\hbox{NH}_{4})_{2}\hbox{S}_{X}$ Treatments

In this letter, electrical characteristics of nanolaminate Al
₂
O
₃
/TiO
₂
/Al
₂
O
₃
on
p
-GaN MOS capacitor with and without PMA and (NH
₄
)
₂
S
_X
treatments were investigated. I-V and C-V characteristics were improved by both PMA and (NH
₄
)
₂
S
_X
treatments. The leakage-current densities can be improved to 3.0 × 10
^-8
and 2.2 × 10
^-8
A/cm
²
at ±1 V, respectively. Almost an ideal C-V curve, the effective dielectric constant of 12.1 and the averaged D
_it
value of 4.3 × 10
¹¹
eV
^-1
· cm
^-2
were obtained.