Patent ID: 9582621
Date: 2017-02-28
CPC Classifications: G06F,H01L

Claim:
1. A method comprising: providing a test integrated circuit chip in a package, the test integrated circuit chip comprising: selecting one of the test devices on the frontside of the substrate to be a heat source and others of the test devices to be sensors, the one of the test devices being at a specific location; biasing the heat source using a supply voltage so as to heat the heat source above a nominal temperature; during the biasing of the heat source, determining changes in temperature relative to the nominal temperature at the heat source and at the sensors; based on the changes in temperature, determining a value of a ratio between a specific imaginary heat amount at a point off the backside of the substrate and an actual heat amount at the heat source, wherein the point off the backside of the substrate is aligned vertically with the specific location of the one of the test devices on the frontside of the substrate and wherein distances between the backside of the substrate and the point and between the backside of the substrate and the specific location are equal; and, storing, in memory, the value of the ratio, the value of the ratio being associated with the specific location and being stored so as to be available for use in generating thermal models of localized temperature changes on a functional integrated circuit chip.