Optimal design of a microthermoelectric cooler for microelectronics

• Published in: Microelectronics Vol. 42; no. 5; pp. 772 - 777
• Main Authors: Kim, Hyunse, Joong Kim, Ook, Hoon Lee, Kong, Elimelech, Menachem
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2011
• Subjects: Computer simulation; Coolers; Exact solutions; Finite element method; Finite element methods (FEM); Mathematical analysis; Mathematical models; Microthermoelectric cooler (μ-TEC); Optimization; Taguchi Methods; Thermoelectricity; Taguchi Methods; Microthermoelectric cooler (μ-TEC); Finite element methods (FEM)
• ISSN: 1879-2391; 0026-2692; 1879-2391
• DOI: 10.1016/j.mejo.2011.01.007

In this paper, performance analysis using finite element methods (FEM) was carried out to develop a microthermoelectric cooler (μ-TEC) for maintaining the chip temperatures under the operating limitation. The performance evaluation process using the Ansys FEM software is described. The effects of the geometries of the thermoelectric columns and the thicknesses of connecting electrodes were investigated. The governing equations for the μ-TEC element were developed and the analytical solutions of the heat absorbed at the cold side of a single μ-TEC element were obtained using the derived equations. The FEM calculation results agreed well with the analytic solutions. Based on these results, the geometries and dimensions of the μ-TEC element were optimized using Taguchi Methods for maximizing the heat absorbed at the cold side of the μ-TEC. The experimental plan using an Orthogonal Array L9 (34) is described in detail. Nine different μ-TEC models were simulated using FEM and the design parameters were optimized. The optimal width to depth ratio (width/depth) was found to be 3.6 (600μm/167μm) and the optimized thicknesses of the thermoelectric column and the gold electrode were 25 and 2μm, respectively. The obtained optimal distance between the P-type and the N-type columns was found to be 35μm. Finally, the absorbed heat of the optimized μ-TEC was calculated. The obtained value was 72.1mW, which agreed well with the predicted value of 75.7mW. At the end, the electrical contact resistance was considered and the calculated performance was 72.2mW, which is a little smaller result than the analytic solution of 72.5mW without the contact resistance.