A temperature change of a device on an integrated circuit chip due to self-heating and thermal coupling with other device(s) is modeled considering inefficient heat removal from the backside of the chip. To perform such modeling, ratios of an imaginary heat amount to an actual heat amount for different locations on the IC chip must be predetermined using a test integrated circuit (IC) chip. During testing, one test device at one specific location on the test IC chip is selected to function as a heat source, while at least two other test devices at other locations on the test IC chip function as temperature sensors. The heat source is biased and changes in temperature at the heat source and at the sensors are determined. These changes are used to calculate the value of the imaginary heat amount to actual heat amount ratio to be associated with the specific location.