Effect of Large Uniaxial Stress on the Thermoelectric Properties of Microcrystalline Silicon Thin Films

This study reports on the behaviour of the thermoelectric properties of n- and p-type hydrogenated microcrystalline silicon thin films (mu c-Si: H) as a function of applied uniaxial stress up to +/- 1.7%. mu c-Si: H thin films were deposited via plasma enhanced chemical vapour deposition and thermoelectric properties were obtained through annealing at 200 degrees C (350 degrees C) for n-(p-) type samples, before the bending experiments. Tensile (compressive) stress was effective to increase the electrical conductivity of n-(p-) type samples. Likewise, stress induced changes in the Seebeck coefficient, however, showing an improvement only in electron-doped films under compressive stress. Overall, the addition of elevated temperature to the bending experiments resulted in a decrease in the mechanical stability of the films. These trends did not produce a significant enhancement of the overall thermoelectric power factor, rather it was largely preserved in all cases.

Automated summary

This study investigates the impact of stress on the thermoelectric properties of hydrogenated microcrystalline silicon thin films. The results show that tensile stress increases conductivity while compression stress improves the Seebeck coefficient of electron-doped films. However, elevated temperature reduces the mechanical stability and has minimal effect on the overall thermoelectric power factor.