Novel Test Structures for Dedicated Temperature Budget Determination

We present a novel method for determining the temperature budget of the process side of silicon substrates and chips, based on well-known silicide formation reactions of metal-Si systems and (four-point probe) resistance measurements. In this paper, we focus on the Pd-Si system that is most temperature sensitive in the range from 100°C to 200°C. A variety of test structures is introduced to exploit the specific properties of the diffusion-limited reaction between Pd and Si. Among others, this resulted in gap-based layouts that facilitate an extension of the temperature range to 350°C. Designs and measurement results are presented, indicating the practicality and the robustness of the proposed technique.