Method of fabrication of on-chip heat pipes and ancillary heat transfer components

Abstract

The density of components in integrated circuits (ICs) is increasing with time. The density of heat generated by the components is similarly increasing. Maintaining the temperature of the components at reliable operating levels requires increased thermal transfer rates from the components to the IC package exterior. Dielectric materials used in interconnect regions have lower thermal conductivity than silicon dioxide. This invention comprises a heat pipe located in the interconnect region of an IC to transfer heat generated by components in the IC substrate to metal plugs located on the top surface of the IC, where the heat is easily conducted to the exterior of the IC package. Refinements such as a wicking liner or reticulated inner surface will increase the thermal transfer efficiency of the heat pipe. Strengthening elements in the interior of the heat pipe will provide robustness to mechanical stress during IC manufacture.