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I am a researcher at Brunel University and have spent the last three
and a half years developing processes to produce low-cost
thermoelectric devices for low temperature heat harvesting.
Our expertise and emphasis has always been on high volume
manufacture, and originally we were looking at adapting printing
processes to produce temperature sensors ('Printed thick-film
thermocouple sensors' S. Duby, B.J. Ramsey, and D.J. Harrison,
Electronics Letters - 17 March 2005 - Volume 41, Issue 6, p. 312-314).

Since then we have moved on to thin film processes and thermoelectric
power generation. We have been generously funded by the EPSRC over
the years and have managed to develop a simple three-step manufacture
process for the production of complete thin-film thermoelectric
devices. The process has the advantage of requiring no pattern
registration and being designed specifically for high-volume
production techniques such as sputtering and thermal evaporation.
This means that entire devices can be manufactured using one reel-to-
reel, non-stop processing envelope on a single piece of deposition
equipment. We are hoping that this will afford significant cost
reductions.

The vast majority of this work has concentrated on process
development rather than materials optimisation and we have up to now
been using thermal evaporation processes to lay down pure metals as
the active elements. We have however recently made contact with an
organisation with large reel-to-reel sputtering facilities who are
keen to collaborate. The advantage with sputtering is that it opens
up the possibility of depositing more exotic materials and
semiconducting compounds such as iron-disilicide. This in turn
suggests the potential to significantly increase the output of our
generators.

I am no materials expert, and as we are currently deciding whether to
put together a proposal for continued funding for this project, I am
doing a little bit of research on whether there is anybody out there
who might be interested in the work we are doing and might be keen
bring their expertise to bear on the question of materials and offer
advice on, in particular, low-cost, non-toxic thermoelectric thin films.