Publication: Electrical properties of silicon supersaturated with titanium or vanadium for intermediate band material
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We have fabricated titanium and vanadium supersaturated silicon layers on top of a silicon substrate by means of ion implantation and pulsed laser melting processes. This procedure has proven to be suitable to fabricate an intermediate band (IB) material, i.e. a semiconductor material with a band of allowed states within the bandgap. Sheet resistance and Hall mobility measurements as a function of the temperature show an unusual behavior that has been well explained in the framework of the IB material theory, supposing that we are dealing with a junction formed by the IB material top layer and the n-Si substrate. Using an analytical model that fits with accuracy the experimental sheet resistance and mobility curves, we have obtained the values of the exponential factor for the thermically activated junction resistance of the bilayer, showing important differences as a function of the implanted element. These results could allow us to engineer the IB properties selecting the implanted element depending on the required properties for a specific application.
Spanish Conference on Electron Devices (9.2013.Valladolid, España). Authors would like to acknowledge the CAI de Técnicas Físicas of the Universidad Complutense de Madrid for the ion implantations and metallic evaporations. This work was partially supported by the Project NUMANCIA II (Grant No. S-2009/ENE/1477) funded by the Comunidad de Madrid. Research by E. García-Hemme was also supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM). J. Olea and D. Pastor thanks Professor A. Martí and Professor A. Luque for useful discussions and guidance and acknowledge financial support from the MICINN within the program Juan de la Cierva (JCI-2011-10402 and JCI-2011-11471), under which this research was undertaken.
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