Thermal management using microelectromechanical systems bimorph cantilever beams

A cooling structure for a heat source, the cooling structure comprising:

• a plurality of beams having a first end and terminating at a second end, the plurality of beams having a plurality of different lengths defined between the first and second ends, each beam formed at least in part of a first conducting material having a first thermal coefficient of expansion and a second conducting material having a second thermal coefficient of expansion, where the first thermal coefficient of expansion is different from the second thermal coefficient of expansion,
• the first end of each beam thermally connected to the heat source, such that heat generated by the heat source is conducted along the length of the beam to the second end of each beam,
• where the heat conducted through each beam causes each beam to deflect as the first and second materials expand differently due to the difference in the first and second thermal coefficients of expansion,
• where characteristics of each beam are selected such that the second end of each beam makes thermal contact with a heat sink as a temperature of the heat source increases, the beam thereby conducting heat away from the heat source to the heat sink and assisting to lower the temperature of the heat source;
• wherein the heat source and the heat sink are connected to a substrate and the beam extends across the substrate between the heat source and the heat sink;
• and
• wherein the plurality of beams include a first plurality of beams positioned at an intermediate location of the cooling structure, a second plurality beams and a third plurality of beams positioned on either side of the first plurality of beams, and wherein the second and third plurality of beams are shorter in length relative to the first plurality of beams.