The contribution of structure of microchannel heat sink and ge-ometry of channel passage have significant role in increasing cooling rate in electronics compact components amongst the pas-sive enhancement techniques. Enhancement of heat dissipation at considerable pumping power penalty is the challenge for the re-searchers. Because in most cases of investigations, it is perceived that enhancement of performance of microchannels is possible by virtue of certain pumping loss. This paper is presenting the overview of the available literatures on such relevant research works. Intermixing of fluid layers, interception of boundary layer by introduction of roughness, bifurcation, secondary flow in the channel enhance performance deliberately in microchannel heat sink. In one of such studies, maximum Nu/Nuo of 2.12 was eval-uated at Re = 589.