Design and optimization of solid state energy conversion devices for electronic equipment

Microprocessor functionality continues to increase while transistor features are shrinking at a pace predicted by Moore's law. The additional number of transistors and smaller features conspire to increase the amount of generated heat-per-area of silicon, requiring improved thermal solutions. While the burden for dissipating heat is increasing for electronic devices, the parametric range over which the thermal engineer must design is being reduced due to cost, weight, size, and energy constraints. The semiconductor industry is requesting novel thermal technologies to meet future product needs. In general, the thermal management issues surrounding electronic equipment are becoming more challenging to solve.; One technology for thermal management of electronic equipment that has not been thoroughly explored is solid state energy conversion in the form of thermoelectric (TE) devices. A significant advantage that TE devices enjoy over conventional technologies is that they can be used for refrigeration and electricity generation. This thesis explores the use of TE devices for managing the thermal design of electronic equipment incorporating these two processes.; Both the refrigeration and generation studies illustrate that in order to fully appreciate the advantages of thermal management with TE, the overall system must be designed within the context of the application. Equations developed for system level analysis are used to study the influence of system level parameters on overall electronic performance. Experimental measurements of the more novel generation process corroborate the analytic models developed. With the help of these models, optimization expressions are developed for each of the model parameters. The culmination of the work is the design and assembly of a prototype that uses a TE module to generate electricity from the heat dissipated by a 25 W microprocessor. The electricity is used to directly power a fan that blows air across heat sinks that keep the heat source temperature below 85°C. The prototype is quite possibly the first successful demonstration of such ‘heat-driven’ cooling of an electronic device.