Modeling, Simulation and Analysis of Temperature Distribution in a Heat Sink Mirosław Gierczak, Piotr Markowski and Andrzej Dziedzic Faculty of Microsystem Electronics and Photonics, Wrocław University of Technology, Poland Abstract: Modeling, simulation and analyses of temperature distribution in a heat-sink are presented in this paper. Laboratory model of processor - source of heat was designed and realized. Four different heaters were fabricated as thick-film resistors screen-printed on alumina substrate. Temperature distribution was monitored using experimental measurements as well as numerical simulations. A measurement system consists of measuring table with structure (heater), heat-sink and two pyrometers, DC power supplies, data acquisition unit and computer. The experimental results were comparable to the results of numerical simulations carried out for similar processor/heat-sink system. This confirm the correctness of the used simulation model. On this basis the numerical analyses were extended - the influence of various factors (such as shape and size of the heat-sink, the presence of the cooling fan) on the heat distribution in the system was investigated. As a result the information useful in optimization process of the heat-sink was collected. 1. INTRODUCTION The paper focus on measurements as well as the modeling of thermal effects occurring on the processor/heat-sink interface. It is part of a project aimed at increasing the efficiency of high-speed processors using information about a thermal open system consisting of an integrated circuit module and its ambient. In order to investigate the thermal effect on processor and heat sink (a problem known in the literature [1,2]) the laboratory model was prepared. (a) (b) (c) Fig. 1. Fabricated resistors (heaters) on alumina substrates (a), the measuring set-up (b), aluminum heat-sink (c). (a) (b) Fig. 2. Measurement points: a) on the heater; b) on the heater / heat-sink system. Thick-film resistive heaters were screen-printed on alumina substrates (the solution known from the literature [3,4] – Fig. 1a. Four different structures based on different pastes were tested (Tab. 1). The temperature distribution in the processor (thick-film heater) / heat-sink system was investigated. Table 1. Parameters of resistors (thick-film heaters). Structure Paste Heater resistance 1 Heraeus R490A 1.42 Ω 2 Heraeus R400A-10 3.8 kΩ 3 ESL PTC-2611-ISP 95.48 Ω 4 DuPont 2021 208.48 Ω Thick-film heaters (they simulate processor) were screen-printed as 30.5x26 mm 2 rectangles on alumina substrate (37.5x32x0.26 mm 3 ). Then the effectiveness of heaters was investigated. The tested heater was powered by a constant power and a temperature changes in several specific points of the system were monitored. These points are indicated in Fig. 2 – for the system without (Fig. 2a) and with (Fig. 2b) the heat-sink. An aluminum plate (100x100x10 cm 3 ) was used as a heat-sink. The heater was mounted on four needle probes (heater-side down) – Fig 1b. On the top (alumina-side of the heater) the thermal grease and the 978-1-5090-1389-0/16/$31.00 ©2016 IEEE 122 2016 39th International Spring Seminar on Electronics Technology (ISSE)