Porous silicon modification

MAGNETIC-FIELD-INDUCED MODIFICATION OF POROUS SILICON SURFACE AND PHOTOLUMINESCENCE... 

Figure 1. Effect of magnetic field on the modification of chemical composition of porous silicon during its ageing in air.

R. C. Anderson, R. S. Muller, and C. W. Tobias, Chemical surface modification of porous silicon, J. 

A. Bsiesy, F. Gaspard, R. Herino, M. Ligeon, E. Muller, R. Romestain, and J. C. Vial, Voltage-induced modifications of porous silicon luminescence. Thin Solid Films 255, 80, 1995. 

Gurtner C, Wun AW, Sailor MJ (1999) Surface modification of porous silicon by electrochemical reduction of organo halides. Angew Chem hit Ed 38 1966-1967... 

Porous silicon (PS) is one of the nanoscale modifications of silicon. There are various approaches to PS producing that are now in use. The technique most generally employed today is known as wet anodization of a crystalline silicon. With this technique, yield parameters of porous material (porosity, pore size and shape, interpore distance) may be readily varied by anodization regimes. However, it is well known the problem of the PS stability influencing the physical properties of the PS layers. P S instability is c onditioned b y very large specific surface area of the porous material. 

A number of studies has been attempted to stabilize porous silicon low-temperature oxidation in a controlled way [1-3], surface modification of silicon nanocrystallites by chemical [4] or electrochemical [5] procedures etc. Rapid thermal processing (RTP) is thought to be a shortcut method of the PS stabilization for a number of purposes. However, there is no data about RTP influence on the PS structure. Therefore, the study of lattice deformations of PS layers after RTP is of great interest. In the present work. X-ray double-crystal diffractometry was used to measure lattice deformations of PS after RTP of millisecond and second durations. 

Lauerhass, X M. and Sailor, M. X Chemical Modification of the Photoluminescence Quenching of Porous Silicon , (1993) Science, 26,11567-68. 

Modification of Porous Silicon Layers with Silanes... 

Keywords Porous Silicon / Silanes / Surface Modification / Vibrational Spectroscopy... 

On the basis of these results modification of porous silicon layers was also carried out with functionalized silanes of the type X3 Me Si-(CH2)m-Y [with X = OMe, OEt n = 0, 2, m > 1 Y = C=C, Cl, epoxy and benzyl group]. In all cases, the IR spectra indicate an anchoring of the silanes on the substrate. Figure 4 shows the CH stretching region of some difference IR spectra of modified PSLs. 

Table 2 List of cells cultured on porous silicon with dififerent surface modifications and a summary of the findings of ...

In conclusion, porous silicon can support the growth and proliferation of cells, but this can be modulated through the use of various surface modification techniques. Pore dimensions also play a crucial role in cell attachment and differentiation, and individual cell types show different responses to surface features. Gradients of pore sizes and surface chemistries can help assess the optimal pore dimensions and surface feature to achieve a certain cell behavior. Finally, researchers studying cell viability on porous silicon should pay careful attention to possible interferences from the porous silicon substrate. 

Thompson CM, Nieuwoudt M, Ruminski AM, Sailor MJ, Miskelly GM (2010) Electrochemical preparation of pore wall modification gradients across thin porous silicon layers. Langmuir 26(10) 7598-7603... 

Gurtner C, Wun AW, Sailor MJ (1999) Surface modification of porous silicon by electrochemical reduction of organo halides. Angew Chem Int Ed 38 1966-1968 Hamadache F, Duvail JL, Scheuren V, Piraux L, Poleunis C, Bertrand P, Belkaid MS (2002) Electrodeposition of Fe-Co alloys into nanoporous p-type silicon influence of the electrolyte composition. J Mater Res 17 1074-1084... 

Song JH, Sailor MJ (1999) Chemical modification of crystalline porous silicon surfaces. Comment Inorg Chem 21 69-84... 

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