Layout to circuit extraction for three-dimensional thermal-electrical circuit simulation of device structures

In this paper, a method is proposed for extraction of coupled networks from layout information for simulation of electrothermal device behavior. The networks represent a three-dimensional (3-D) device structure with circuit elements. The electrical and thermal characteristics of this circuit representation are calculated with a circuit simulator. Spatial potential distributions, current flows, and temperature distributions in the device structure are calculated on the spatial coordinates. This simulation method can be placed between device simulation and (conventional) circuit simulation. It has been implemented in a circuit simulator and is demonstrated for simulation of self-heating in a bipolar low frequency power transistor. The main advantage of this simulation method is that not only the 3-D thermal behavior of the whole chip is simulated, but that this is also directly coupled to the electrical device behavior by means of the power dissipation and temperature distribution in the device. This offers the possibility for the circuit designer to simulate 3-D, coupled, thermal-electrical problems with a circuit simulator. As an example, the influence of the emitter contacting on the internal temperature and current distribution of a BJT is investigate

Comprehensive physical modeling of NMOSFET hot-carrier-induced degradation

The role of hot-carrier-induced interface states in NMOSFETs is discussed. A new model is proposed based on measurements in several 0.7¿m CMOS technologies of different suppliers. Our model for the first time enables accurate interface state prediction over many orders of magnitude in time for all stress conditions under pinch-off and incorporates saturation. It can easily be implemented in a reliability circuit simulator, enabling more accurate NMOSFET parameter degradation calculations(e.g. ¿ID ¿gm etc.)

An empirical model for early resistance changes due to electromigration

A new heuristic description for electromigration-induced early resistance changes is given. The basis is formed by two coupled partial differential equations, one for vacancies, and one for imperfections. These equations are solved numerically for a grain boundary bamboo structure. It is shown that this model is capable of simulating the typical effects as observed in early resistance change measurements. These early resistance changes are due to the redistributions of the vacancies and the generation of imperfections. Simulations are performed that closely match the measured resistance change curves

Modeling of the collector epilayer of a bipolar transistor in the MEXTRAM model

A new model description for the behaviour of epitaxial collectors in bipolar transistors is given. This is part of MEXTRAM, a compact model for circuit simulation, and it gives the voltage drop and stored minority carrier charge in the collector epilayer as a function of the bias conditions. It covers (total) depletion and quasi-saturation for both ohmic and space charge conditions in the end region of the epilayer. New features are that the collector current and stored charge are given as explicit analytical functions, thus guaranteeing continuity also for their derivatives, and that collector current spreading is taken into accoun

Modeling of the collector epilayer of a bipolar transistor in the MEXTRAM model

A new model description for the behaviour of epitaxial collectors in bipolar transistors is given. This is part of MEXTRAM, a compact model for circuit simulation, and it gives the voltage drop and stored minority carrier charge in the collector epilayer as a function of the bias conditions. It covers (total) depletion and quasi-saturation for both ohmic and space charge conditions in the end region of the epilayer. New features are that the collector current and stored charge are given as explicit analytical functions, thus guaranteeing continuity also for their derivatives, and that collector current spreading is taken into accoun