Method for extracting non-linear thermal resistance of transistor

Abstract

The invention relates to a method for extracting non-linear thermal resistance of a transistor. In the conventional method, thermal resistance values extracted at different power levels are not a constant, so that the problems of difficulty in determination of the thermal resistance and the like are easy to cause. The method comprises the following steps of: establishing relations between the thermal resistance Rth of the transistor and direct current power dissipation Pd as well as model parameters RO, RA and RB, relations between the direct current power dissipation Pd and drain current Ids as well as drain-source voltage Vds and relations among a junction temperature Tj, an external temperature TA, the thermal resistance Rth and the direct current power dissipation Pd so as to determine the relation among variations; calculating the variation delta Ids of the Ids of fixed gate-source voltage along with the variations of the Tj and the Vds; measuring the relation characteristic of drain current and drain voltage under the conditions of different external temperatures and fixed gate voltage; and finally obtaining the thermal resistance according to the measured parameters and a model. The method is simple and efficient.

Description

technical field [0001] The invention belongs to the field of integrated circuits, and relates to integrated circuit device model technology, in particular to the extraction technology of thermal resistance models of power transistors in integrated circuits. Background technique [0002] Thanks to its high power density and breakdown voltage, such as GaAs, GaN MESFET / HEMT, and Si-based high-voltage LDMOSFET, SOI LDMOSFET, etc. are widely used in the design of high-frequency power integrated circuits. Due to their high power density, these devices typically operate at very high junction temperatures. Thermal resistance is one of the important parameters to describe the input / output power loss caused by the self-heating effect of the transistor. The accurate extraction of this parameter is of great significance for accurately predicting the change of device junction temperature and the change of output characteristics under different input power levels. Thermal resistance is a...

AI Technical Summary

Problems solved by technology

[0014] The nonlinear characteristics of thermal conductivity / thermal resistance and junction temperature of semiconductor materials have long been known, and the above formula uses the constant R th The method of calculating the junction temperature actually ignores this characteristic, and the calculated junction temperature may be too small in actual application; the thermal resistance extraction method using the assumption of constant thermal resistance, the thermal resistance value extracted under different power levels is not constant, easy Leading to problems such as thermal resistance is difficult to determine

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