Abstract: A method of making mesoporous silicon from silica, the mesoporous silicon obtained by the method, and uses of the mesoporous silicon are described. The mesoporous silicon may be derived from plants, particularly land-based plants.

Abstract: A method of making porous silicon using a chemical etchant comprising metal ions is described.

Abstract: Oral hygiene compositions suitable for use as dentifrice compositions comprising a silicon abrasive agent are provided.

Abstract: A method of making mesoporous silicon from silica, the mesoporous silicon obtained by the method, and uses of the mesoporous silicon are described. The mesoporous silicon may be derived from plants, particularly land-based plants.

Abstract: A method of making porous silicon using a chemical etchant comprising metal ions is described.

Abstract: The invention relates to the use of a silicon-containing material to reduce the amount of hormone required in a method of hormone treatment to achieve a desired response, particularly in hormone replacement therapy (HRT) and especially in the maintenance of post-menopausal bone health and the management or treatment of osteoporosis, and to pharmaceutical compositions for use in such a method.

Abstract: A chewing gum composition comprising porous silicon is described.

Abstract: The use of silicon as an imaging agent is described.

Abstract: Oral hygiene compositions suitable for use as dentifrice compositions comprising a silicon abrasive agent are provided.

Abstract: The invention relates to the use of silicon in food.

Abstract: The present invention relates to a method of packaging a packageable product comprising the step of placing the packageable product and a silicon material within a package. The packageable product may be a food or a drink. The silicon material may comprise porous silicon, for example it may comprise films or particles of vivid colour. The silicon material may be used to absorb substances that are harmful to the packageable product. The silicon material may be used to release substances that are beneficial to the packageable product.

Abstract: An electroluminescent device (10) comprises a porous silicon region (22) adjacent a bulk silicon region (20), together with a top electrical contact (24) of transparent indium tin oxide and a bottom electrical contact (26) of aluminum. The device includes a heavily doped region (28) to provide an ohmic contact. The porous silicon region (22) is fabricated by anodizing through an ion-implanted surface layer of the bulk silicon. The silicon remains unannealed between the ion-implantation and anodization stages. The device (10) has a rectifying p-n junction within the porous silicon region (22).

Abstract: An electroluminescent device (10) comprises a porous silicon region (22) adjacent a bulk silicon region (20), together with a top electrical contact (24) of transparent indium tin oxide and a bottom electrical contact (26) of aluminum. The device includes a heavily doped region (28) to provide an ohmic contact. The porous silicon region (22) is fabricated by anodizing through an ion-implanted surface layer of the bulk silicon. The silicon remains unannealed between the ion-implantation and anodization stages. The device (10) has a rectifying p-n junction within the porous silicon region (22).

Abstract: A method of making semiconductor quantum wires employs a semiconductor wafer (14) as starting material. The wafer (14) is weakly doped p type with a shallow heavily doped p layer therein for current flow uniformity purposes. The wafer (14) is anodised in 20% aqueous hydrofluoric acid to produce a layer (5) microns thick with 70% porosity and good crystallinity. The layer is subsequently etched in concentrated hydrofluoric acid, which provides a slow etch rate. The etch increases porosity to a level in the region of 80% or above. At such a level, pores overlap and isolated quantum wires are expected to form with diameters less than or equal to 3 nm. The etched layer exhibits photoluminescence emission at photon energies well above the silicon bandgap (1.1 eV) and extending into the red region (1.6-2.0 eV) of the visible spectrum.

Abstract: Porous semiconductor material in the form of at least partly crystalline silicon is produced with a porosity in excess of 90% determined gravimetrically, and voids, crazing and peeling are substantially not observable by scanning electron microscopy at a magnification of 7,000. The porous silicon is dried by supercritical drying. The silicon material has good luminescence properties together with good morphology and crystallinity.

Abstract: A method of making semiconductor quantum wires, and a light emitting device employing such wires, employs a semiconductor wafer as starting material. The wafer is weakly doped p type with a shallow heavily doped p layer therein for current flow uniformity purposes. The wafer is anodized in 20% aqueous hydrofluoric acid to produce a layer 5 microns thick with 70% porosity and good crystallinity. The layer is subsequently etched in concentrated hydrofluoric acid, which provides a slow etch rate. The etch increases porosity to a level in the region of 80% or above. At such a level, pores overlap and isolated quantum wires are expected to form with diameters less than or equal to 3 nm. When excited, the etched layer exhibits photoluminescence emission at photon energies well above the silicon bandgap (1.1 eV) and extending into the red region (1.6-2.0 eV) of the visible spectrum.

Abstract: A method of making semiconductor quantum wires employs a semiconductor wafer (14) as starting material. The wafer (14) is weakly doped p type with a shallow heavily doped p layer therein for current flow uniformity purposes. The wafer (14) is anodised in 20% aqueous hydrofluoric acid to produce a layer (5) microns thick with 70% porosity and good crystallinity. The layer is subsequently etched in concentrated hydrofluoric acid, which provides a slow etch rate. The etch increase porosity to a level in the region of 80% or above. At such a level, pores overlap and isolated quantum wires are expected to from with diameter less than or equal to 3 nm. The etched layer exhibits photoluminescence emission at photon energies well above the silicon bandgap (1.1 eV) and extending into the red region (1.6-2.0 eV) of the visible spectrum.

Abstract: A method of making semiconductor quantum wires employs a semiconductor wafer as starting material. The wafer is weakly doped p type with a shallow heavily doped p layer therein for current flow uniformity purposes. The wafer is anodised in 20% aqueous hydrofluoric acid to produce a layer microns thick with 70% porosity and good crystallinity. The layer is subsequently etched in concentrated hydrofluoric acid, which provides a slow etch rate. The etch increases porosity to a level in the region of 80% or above. At such a level, pores overlap and isolated quantum wires are expected to form with diameters less than or equal to 3 nm. The etched layer exhibits photoluminescence emission at photon energies well above the silicon bandgap (1.1 eV) and extending into the red region (1.6-2.0 eV) of the visible spectrum.