MSM 98
MSM 98
Technical Proceedings of the 1998 International Conference on Modeling and Simulation of Microsystems

Applications: Semiconductors Chapter 9

Simulations of a New CMOS Compatible Method to Enhance the Breakdown Voltage of Highly-Doped Shallow PN Junctions

Authors: A. Pauchard, P.A. Besse and R.S. Popovic

Affilation: EPFL, Switzerland

Pages: 420 - 425

Keywords: avalanche breakdown, field limiting ring, metal field plate, shallow junction, CMOS

Avalanche breakdown often limits the working range of planar junction diodes in electronic circuits and in sensors. We present two-dimensional device simulation results (using MEDICI) of a novel CMOS compatible structure. It combines a floating field limiting ring and a metal field plate in order to enhance the breakdown voltage Vbd of highly-doped shallow planar junctions. Electrical simulations have shown that a single field limiting ring is effective in increasing Vbd only if placed at a distance d smaller than 300nm. For d=lOOnm, breakdown even occurs over the plane diode. At distance d=4OOnm, the field ring can enhance the breakdown voltage only if combined with a metal field plate. Vbd increases linearly with negative applied gate voltage, with a proportionality factor of about 0.1. For a gate voltage of -1OV, Vbd increases by about 12 % up to -12.8 V. Measurements on diodes integrated in standard industrial CMOS 0.5 1lm process corroborate with simulation results.

ISBN: 0-96661-35-0-3
Pages: 678