Micropower thermoelectric generator from thin Si membranes

• We describe the microfabrication of a planar CMOS compatible Si-based generator.
• The device contains a 100 nm thick Si membrane with embedded n,p doped regions.
• A power output of 4.5 µW/cm2 is achieved for a temperature difference of 5.5 K.
• The chip could be suited for body-energy scavenging to feed low-power devices.

We report the development of a Si-based micro thermogenerator build from silicon-on-insulator by using standard CMOS processing. Ultrathin single-crystalline Si membranes, 100 nm in thickness, with embedded n and p-type doped regions electrically connected in series and thermally in parallel, are active elements of the thermoelectric device that generate thermopower under various thermal gradients. This proof-of-concept device produces an output power density of 4.5 µW/cm2, under a temperature difference of 5 K, opening the way to envisage integration as wearable thermoelectrics for body energy scavenging.

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