3d Electrothermal Simulation of Heterostructure Thin Film Micro-coolers

1 Contact author e-mail: [email protected] ABSTRACT A 3D electrothermal model is used to simulate and optimize Si/SiGe superlattice heterostructure micro-coolers. The model considers thermoelectric/thermionic cooling, heat conduction and Joule heating. It also includes non-ideal effects, such as contact resistance between metal and semiconductor, substrate/heatsink thermal resistance, the side contact resistance. The simulated results match very well with the experimental cooling curves for various device sizes ranging from 60x60μm up to 150x150μm. It is found that the key factor limiting maximum cooling is metalsemiconductor contact resistance. The maximum cooling could be doubled if we remove the metal-semiconductor contact resistance. The thin film Si/SiGe superlattice micro-coolers can provide cooling power density over 500 W/cm as compared with a few W/cm of bulk Bi2Te3 themoelectric coolers. This micro -cooler experimentally demonstrated a maximum cooling of 4.5oC at room temperature and 7oC of cooling at 100oC ambient temperature. It is a promising candidate for microprocessor spot cooling.