Modeling of geometrically scalable integrated finger diodes

Abstract

A modeling approach for geometrically scalable integrated short length finger diodes is presented. Such diodes cannot be modeled by the usual area/perimeter modeling approach especially if the ends of the finger exhibit different doping profiles compared to the longitudinal parts and if a short length multi-finger configuration is used. These configurations can be either modeled through a four diode physics based model or by using effective parameters. This paper deals with the first option. A dedicated test chip containing 9 finger diodes differing in size has been designed and characterized at room temperature. The modeling approach is explained and a comparison between the state-of-the-art and the physical modeling approach is shown. 2D TCAD simulations of a short length 5 finger diode has been performed in order to confirm the basic characteristics of the current distribution between the finger terminals.