Cost-effective thermoelectric cooler packaging using hybrid Cu paste

A cost-effective and simple thermoelectric cooler (TEC) module packaging is proposed using new die attachment material of hybrid Cu paste (HCP). Silver paste has widely used in TEC module, it generally showed poor shear strength regarding high material cost and high temperature of sintering process. Cost-effective HCP material, which is composed of Ag coated Cu flakes, solder powders, and a fluxing resin, is proposed to compensate the weakness of silver paste. By optimizing the volumetric ratio of the Ag coated Cu flakes, solder powders, and the fluxing resin, screen printing and curing process for die attachment are successfully developed. TEC module using HCP is fabricated with 128 pairs of P- and n-type TE legs and a fabricated TEC module size is 40 mm × 40 mm. In this work, DC resistance and cooling capacity of the TEC module are measured and compared with the conventional module using silver paste to evaluate the proposed HCP. The suggested TEC packaging method which has the two advantages of the low cost and process simplification works well.