A means to properly size rectangular heat spreaders between a dielectric layer connected to thermal ground and a power device is developed by modeling the problem as a thermal resistance network. Generalized formulas and nondimensional charts to optimize heat spreader thickness and footprint are presented. The power device and heat spreader are assumed to be (concentric) rectangular solids of arbitrary length, width and thickness. The nondimensional results are validated by finite element analysis (FEA) and examples demonstrate the utility of the methodology to thermal design engineers.

Issue Section:
Technical Papers
Keywords:
thermal management (packaging), finite element analysis, thermal resistance
Topics:
Flat heat pipes, Thermal resistance, Finite element analysis, Heat
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Copyright © 2001
 by ASME
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