Fast and Accurate Emissivity and Absolute Temperature Maps Measurement for Integrated Circuits

Abstract

The comparison of temperatures between measurement and simulation (i.e., temperature correlation) is commonly needed in many thermal studies. However, existing methods to measure temperature maps are either inaccurate or inconvenient due to various assumptions or measurement conditions needed. It still remains a missing piece in the literature how to accurately and flexibly measure temperature maps. Toward this, we propose a practical and feasible method for emissivity map measurement. Two reference plates are utilized to obtain an emissivity map, from which real emissivity value of each pixel of the infrared thermographer is obtained. According to the experimental results herein, the deviation of the emissivity measured using this method is on the order of 0.01, consistent with the minimum resolution of all currently available infrared thermographic instruments. With the emissivity map, highly accurate temperature map is then obtained. The method can be flexibly applied to various test samples whether the emissivity of the test sample changes with the wavelength or not. Experimental results on real ICs indicate that compared with commonly used infrared thermographer with uniform emissivity setting or black coating approaches, our method can obtain significantly better temperature correlation.