Experimental characterization of Si micropillar based evaporator for advanced vapor chambers

Advanced thermal management technologies have become more and more essential in semiconductor industries in order to spread high heat flux from integrated circuits and ensure a reliable operation of the devices. Vapor chamber has been extensively studied since it has superior heat dissipation capabilities in comparison with other cooling techniques. Among the components of a vapor chamber, evaporator has proven to be the governing factor in enhancing the entire vapor chamber´s performance. In this paper, silicon based cylindrical micropillar based evaporators were fabricated and characterized inside a vacuum chamber. Geometric influence on the micropillar evaporator´s heat transfer performance were investigated. Higher pillar diameter/ pitch ratio, higher aspect ratio and low wick array lengths are required for more efficient heat spreading.