Title :
A novel cross-coupled inter-poly-oxide capacitor for mixed-mode CMOS processes
Author :
Ming-Jer Chen ; Chin-Shan Hou
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
fDate :
7/1/1999 12:00:00 AM
Abstract :
The inter-poly-oxide (IPO) capacitor is one of the main elements in present mixed-mode CMOS process technologies. However, the phenomenon of poly depletion causes a significant change in the measured capacitance with applied voltage. This effect, expressed in terms of the voltage coefficient of capacitance (VCC), can seriously deteriorate analog precision. A novel cross-coupled scheme is proposed for the IPO capacitors. The resulting VCC has a very low measured value of 2 ppm/V in a 0.35-μm standard mixed-mode CMOS process, achieved without any unconventional approaches.
Keywords :
CMOS integrated circuits; capacitors; mixed analogue-digital integrated circuits; 0.35 micron; cross-coupled inter-poly-oxide capacitor; mixed-mode CMOS process; poly depletion; voltage coefficient of capacitance; CMOS process; CMOS technology; Capacitance measurement; Capacitors; Conductors; Dielectric constant; Electrodes; Silicides; Tungsten; Voltage;
Journal_Title :
Electron Device Letters, IEEE
