Vaporizable Scaffolds for Fabricating Thermoelectric Modules

A process for fabricating thermoelectric modules with vacuum gaps separating the thermoelectric legs has been conceived, and the feasibility of some essential parts of the process has been demonstrated. The vacuum gaps are needed to electrically insulate the legs from each other. The process involves the use of scaffolding in the form of sheets of a polymer to temporarily separate the legs by the desired distance, which is typically about 0.5 mm. During a bonding subprocess that would take place in a partial vacuum at an elevated temperature, the polymer would be vaporized, thereby creating the vacuum gaps. If desired, the gaps could later be filled with an aerogel for thermal insulation and to suppress sublimation of thermoelectric material, as described in “Aerogels for Thermal Insulation of Thermoelectric Devices” (NPO-40630), NASA Tech Briefs, Vol. 30, No. 7 (July, 2006), page 50.