An Electrowetting-Based Technique for Hot-Spot Cooling of Integrated Circuits: Experimental and Numerical Approach

In this paper, a new method of cooling hot-spots in electronic devices is proposed based on the electrowetting phenomenon. Since the microprocessor technology is developing with a fast rate, conventional cooling methods for integrated circuits will eventually fail to address the needs for high performance computers. As a result, novel methods of cooling must be developed. In this study, a layer with variable and programmable thermal conductivity is placed between the electronic device and a conventional cooling system. This layer is composed of an array of liquid metal drops which can be actuated with the electrowetting phenomenon. The conductivity of this layer can be modified according to the heat transfer requirements of the system in the desired region. This action is accomplished by actuating the drop in that region with an applied AC voltage. To test the possibility of designing such a system, experimental and numerical investigations with different scenarios have been presented and compared in this paper. Two mercury drops with different volumes of 2.8 µL and 6 µL are used in a PCB-based experimental setup to observe the changes in contact angle and apex of the drops under an applied voltage. Also, the Navier-Stokes equations along with the energy equation are solved to investigate the effectiveness of the drops in cooling the hot-spots