Standards Development

Scope

This document specifies a method for measuring the thermal resistance between a heater chip and a cold plate with the heater chip mounted on a metalized ceramic substrate, imitating a SiC high out-put power module; this measurement represents an index of the heat dissipation characteristics of a metallized ceramic substrate used in a high-output power module.

Purpose

The purpose of the proposed standard is to provide a convenient and suitable method for measuring the thermal resistance between a power semiconductor chip mounted on a metalized ceramic substrate and a cold plate for high output power modules, by means of a heater chip imitating a SiC semiconductor device.

Power modules that use semiconductor devices to provide high-efficiency conversion and control of electric power are becoming an extremely important technology from a view point of energy saving. Both output power and power density in semiconductor device are increasing at the same time of size-reduction, and such trend is accelerated by the employment of wide band gap semiconductors like SiC. Under the circumstances, heat-dissipation technologies are also becoming more important than ever. In high-output power modules, metalized ceramic substrates are generally used for electrical insulation. Techniques are available to measure the thermal conductivity of the individual materials comprising metallized ceramic substrates; however, there are no established methods to evaluate the thermal dissipation characteristics of metallized ceramic substrates per se, or the thermal dissipation characteristics of power modules equipped with the metalized ceramic substrate, which are key issues in the design of power modules with a high heat-dissipating efficiency.

Manufacturers of ceramics, heat dissipation materials and parts, modules, and other such devices are recommended to use this standard to evaluate the heat-dissipating characteristics of metallized ceramic substrates under common conditions.