Development of Manufacturing Routes for Oxide Thermoelectrics

The manufacturing of Nb-doped SrTiO3 and different heterostructures will be investigated. The methods include thin film techniques (sputtering and ALD - atomic layer deposition) - and powder metallurgical (P/M) methods. ALD is based on saturating surface reactions of alternately supplied precursor vapors and self-limiting film growth. This provides several advantages, such as atomic level control of the film thickness, area uniformity and conformal coating. Sputtering on the other hand provides more industrial proven deposition method for thin film materials for TEG. P/M includes manufacturing of doped semiconducting powders with sol-gel process and spray drying. Compaction methods are hot pressing and SPS. Applicability of DWTS will be tested. DWTS is a micron scale plasma-assisted thermal spray system developed by Mesoscribe Inc. The expected benefits are low manufacturing costs of TEG components by higher yield of the materials and by simple CAD-based 3D manufacturing process.