In this paper, we compare measurements of the conduction-band (CB) offset in - and -oriented narrow n-type FinFETs with a model taking into account both strain and quantum confinement. We estimate the complete strain tensor for the scarce strain measurement points available with finite-element-method simulations of the thermal expansion effect. We found an inhomogeneous compressive strain that increases for smaller fin widths. The experimental CB offset is extracted from temperature-dependent transfer characteristics. The results show a lowering of the CB edge up to 40 meV for fin widths down to 5 nm. These experimental observations compare well with the model, and hence, the band offset can be explained by both quantum confinement and strain.
- quantum wells
- Leakage current
- Semiconductor device measurement
- Thermal expansion
- Double-gate FETs
van Hemert, T., Kaleli, B., Hueting, R. J. E., Esseni, D., van Dal, M. J. H., & Schmitz, J. (2013). Strain and conduction-band offset in narrow n-type finFETs. IEEE transactions on electron devices, 60(3), 1005-1010. https://doi.org/10.1109/TED.2013.2241765