High-Performance MIM Capacitors Using Zr-Sn-Ti-O Dielectrics Derived from Atomic Layer Deposition

Metal–insulator–metal (MIM) capacitors fabricated with Zr-Sn-Ti-O dielectrics by the plasma-enhanced atomic layer deposition (PEALD) were first demonstrated. By changing the pulse cycle ratio and cycle number of PEALD, the comprehensive electrical properties of the Zr-Sn-Ti-O MIM capacitors were optimized to meet the requirements of system-level chips for the high-density MIM capacitors. When the cycle ratio of ZrO
₂
:SnO
₂
:TiO
₂
is 2:10:2, the sample of Zr
_0.45
Sn
_0.06
Ti
_0.48
O
₂
shows the best electrical properties: a capacitance density of 10.8 fF/
$\mu \text{m}^{{2}}$
, a quadratic voltage linearity of −83 ppm/V
²
, a leakage current density of
$5\times 10^{{-7}}$
A/cm
²
at 3 V, a breakdown voltage of 6.8 V, and a temperature linearity coefficient of 95.1 ppm/°C. These results indicate that PEALD Zr-Sn-Ti-O dielectrics are promising candidates for future high-density MIM capacitor applications in radio frequency and analog-/mixed-signal integrated circuits.