Abstract
Stress is distributed unequally along channels by both uniaxial and biaxial stressors. This study investigated channel-length-related performance enhancement by using contact etching stop layer (CESL) as the stressor. Devices with low tensile (L.T.) and high tensile (H.T.) stresses use CESLs with different thicknesses on nMOSFETs. Results indicate that transconductance enhances the shortest channel in H.T. devices compared with L.T. devices. The threshold voltage difference between L.T. and H.T. nMOSFETs verifies the high stress in H.T. nMOSFETs. However, this threshold voltage difference cannot verify the considerable decrease in the threshold voltage of the shortest channel of H.T. devices compared with L.T. devices.
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Irie, H., Kita, K., Kyuno, K., & Toriumi, A. (2004). In-plane mobility anisotropy and universality under uni-axial strains in NAND p-MOS inversion layers on (100), (110) and (111) Si. In IEDM Technical Digest, pp. 225–228.
Liu, J. P., Li, K., Pandey, S. M., Benistant, F. L., See, A., Zhou, M. S., et al. (2008). Strain relaxation in transistor channels with embedded epitaxial silicon germanium source/drain. Applied Physics Letters, 93, 221912.
Chang, W. T., Wang, C. C., Lin, J. A., & Yeh, W. K. (2010). External Stresses on Tensile and Compressive Contact Etching Stop Layer SOI MOSFETs. IEEE Transactions on Electronics Devices, 57, 1889–1894.
Lim, J. S., Thompson, S. E., & Fossum, J. G. (2004). Comparison of threshold-voltage shifts for uniaxial and biaxial tensile-stressed n-MOSFETs. IEEE Electron Device Letters, 25, 731–733.
Sugii, N., Hisamoto, D., Washio, K., Yokoyama, K. N., & Kimura, S. (2002). Performance enhancement of strained-Si MOSFETs fabricated on a chemical-mechanical-polished SiGe substrate. IEEE Transactions on Electronics Devices, 49, 2237–2243.
Rochettea, F., Casséa, M., Mouisb, M., Reimbolda, G., Blachiera, D., Lerouxa, C., et al. (2007). Experimental evidence and extraction of the electron mass variation in [110] uniaxially strained MOSFETs. Solid-State Electronics, 51, 1458–1465.
Zhao, W., He, J., Belford, R. E., Wernersson, L. E. E., & Seabaugh, A. (2004). Partially depleted SOI MOSFETs under uniaxial tensile strain. IEEE Transactions on Electronics Devices, 51, 317–323.
Yang, P., Lau, W. S., Lai, S. W., Lo, V. L., Siah, S. Y., & Chan, L. (2010). Effects of switching from ‹110› to ‹100› channel orientation and tensile stress on n-channel and p-channel metal-oxide-semiconductor transistors. Solid-State Electronics, 54, 461–474.
Hoshi, Y., Sawano, K., Yamada, A., Nagakura, S., Usami, N., Arimoto, K., et al. (2011). Line width dependence of anisotropic strain state in sige films induced by selective ion implantation. Applied Physics Express, 4, 095701.
Haugerud, B. M., Bosworth, L. A., & Belford, R. E. (2003). Mechanically induced strain enhancement of metal–oxide–semiconductor field effect transistors. Journal of Applied Physics, 94, 4102.
Komoda, T., Oishi, A., Sanuki, T., Kasai, K., Yoshimura, H., Ohno, K., et al. (2004). Mobility improvement for 45 nm node by combination of optimized stress and channel orientation design. In IEDM Technical Digest, pp. 217–220.
Rim, K., Hoyt, J. L., & Gibbons, J. F. (2000). Fabrication and analysis of deep submicron strained-Si n-MOSFET’s. IEEE Transactions on Electronics Devices, 47, 1406–1415.
Acknowledgments
The authors thank the National Science Council for its financial support under contract number 101-2221-E-390-001-MY2, and the staff at United Microelectronics Corporation for their informative discussions.
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© 2014 Springer International Publishing Switzerland
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Chang, WT., Kuo, PH. (2014). Transconductance Enhancement Dependence on the Channel Length of CESL-Strained nMOSFETs. In: Juang, J., Chen, CY., Yang, CF. (eds) Proceedings of the 2nd International Conference on Intelligent Technologies and Engineering Systems (ICITES2013). Lecture Notes in Electrical Engineering, vol 293. Springer, Cham. https://doi.org/10.1007/978-3-319-04573-3_33
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DOI: https://doi.org/10.1007/978-3-319-04573-3_33
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-04572-6
Online ISBN: 978-3-319-04573-3
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