Properties of bilayer contacts to porous silicon

Abstract

The aim of the present work is the growth by PVD techniques and ulterior characterization of electrical contacts to columnar porous silicon (PSi) as an approach to reliable PSi sensor devices. Contacts consist of a NiCr (40:60) and Au bilayer on the PSi surface deposited by magnetron sputtering. These structures show a good adhesion to the rough surface of columnar PSi. The morphology of these electrical contacts is characterized by electron microscopy and their crystalline structure by X-ray diffraction. Compositional profiles are determined by Rutherford backscattering spectroscopy and energy dispersive X-ray spectroscopy, which demonstrate that the infiltration of NiCr into the PSi is at the origin of the metallic thin film adhesion improvement. I -V characteristics and impedance spectroscopy measurements show that this configuration provides rectifying electrical contacts to PSi, for which a simple equivalent circuit based on one resistor and two capacitors can be modeled. These results further support the use of PSi electrical structures for sensing purposes. D. Gallach · V. Torres-Costa · L. García-Pelayo · A. Climent-Font · R.J. Martín-Palma · M. Manso ( )

The Mechanism of Metal-Assisted Etching of Silicon

“…Most of the reports available on gold, copper, palladium, indium, and titanium as contact metals to PSi are found rectifying (Han et al 1994;Jeske et al 1995;Simons et al 1995;Diligenti et al 1996;Ichinohe et al 1996;Angelescu and Kleps 1998;Matsumoto et al 1998;Skryshevsky et al 1998;Slobodchikov et al 1998Slobodchikov et al , 1999Lue et al 1999;Bhattacharya et al 2000;Vikulov et al 2000;Ghosh et al 2002a;Rabinal and Mulimani 2007;Gallach et al 2012). The metal alloys like Au-In, In-Sn, and so on showed rectifying behavior (Angelescu and Kleps 1998).…”

“…Al p Evaporation Deresmes et al 1995;Stievenard and Deresmes 1995;Zimin et al 1995;Angelescu and Kleps 1998;Skryshevsky et al 1998;Martin-Palma et al 1999;Rabinal and Mulimani 2007;Cherif et al 2013 Sputtering Anderson et al 1991;Zimin and Bragin 1999 n Evaporation Zimin et al 1995;Diligenti et al 1996 Sputtering Anderson et al 1991;Zimin and Bragin 1999 Au p Evaporation Angelescu and Kleps 1998;Matsumoto et al 1998;Lue et al 1999;Bhattacharya et al 2000;Rabinal andMulimani 2007 Sputtering Han et al 1994;Ichinohe et al 1996;Gallach et al 2012 Electroless Jeske et al 1995 n Evaporation Simons et al 1995;Diligenti et al 1996 Ag where R s is the series resistance, and I s is the saturation current, which can be expressed as…”

Near ambient pressure X-ray photoelectron spectroscopy monitoring of the surface immobilization cascade on a porous silicon-gold nanoparticle FET biosensor

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Projeto e modelagem de indutores planares para aplicações em circuitos integrados de radiofrequência.

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“…Sendo que YP1 é a admitância para o plano terra da porta P1, assim, reescrevendo (25) em parte real e parte imaginária, fica:…”