Organometallic chemistry on silicon surfaces: formation of functional monolayers bound through Si–C bonds

Abstract

Silicon chips form the backbone of modern computing and yet until recently, the surface chemistry of this technologically essential material has remained relatively unexplored. As the size of devices on silicon wafers shrink (towards gigascale integration), the surface characteristics play increasingly crucial roles in the proper functioning of the device since the ratio of surface atoms/bulk escalates. While surface oxide has served thus far as the main passivation route, there is strong interest in precisely tailoring the interface properties, not only for microelectronics, but other applications including sensors, MEMS and biologically active surfaces. As a result, organometallic and organic chemistry has become essential for the synthesis of functional, modifiable monolayers, bound to non-oxidized silicon surfaces through silicon–carbon bonds. The latest approaches towards preparation of monolayers through Si–C bonds on both flat and photoluminescent porous silicon are described. Wet chemical techniques, accessible to most organometallic/organic chemists are highlighted, but recent developments using UHV conditions also receive attention.

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