Thermoelectric Thin Film Device of Cross-Plane Configuration Processed by Electrodeposition and Flip-Chip Bonding

Abstract

Using electrodeposition and flip-chip bonding, a cross-plane thin film device consisting of 242 pairs of the electrodeposited n-type Bi–Te and p-type Sb–Te thin film legs was successfully fabricated. The electrodeposited Bi–Te films with the thickness of 2.5–20.2 µm exhibited the Seebeck coefficients of −52 to −59 µV/K and the power factors of 5.5–5.1 × 10−4 W/m·K2. While the Seebeck coefficient of the Sb–Te film varied from 276 to 485 µV/K, the power factor was changed from 81 × 10−4 to 50 × 10−4 W/m·K2 with increasing the film thickness from 2.2 to 20.5 µm. The internal resistance of the thin film device consisting of 242 pairs of the electrodeposited n–p thin film legs was measured as 3.7 KΩ. The open-circuit voltage and the maximum output power of the thin film device were 0.294 V and 5.9 µW, respectively, with the temperature difference of 22.3 K across the hot and cold ends of the thin film device.