A stackable heat sink having a core shaft in heat-engaging relation with a semiconductor device and a plurality of individual thin fins having an opening for receiving the core shaft in press fit relation so that a plurality of the fins, when mounted on the shaft, define a plurality of air passageways and the fins and shaft efficiently transfer heat away from the semiconductor device and into the surrounding atmosphere. In an improved version of the heat sink, the heat-dissipating fins may be corrugated so as to increase the surface area of each individual fin without increasing its perimeter. A heat pipe may be used in conjunction with the core shaft or base of the heat sink so as to facilitate heat transfer away from the electronic component. An improved heat sink may also include a base having a plurality of openings and a small fan connected to the portion of the base with the openings, so as to direct air across and between adjacent fins.