Substrates for spatially selective micron and nanometer scale deposition and combinatorial modification and fabrication
A substrate ( 1 ) for spatially selective micron and nanometer scale deposition and/or reaction, which has a support ( 3 ), a conductive layer ( 5 ) on the support, a dielectric layer ( 7 ) to hold an electrostatic charge pattern such as a photoconductive layer of a material which dissipates an electric charge upon receiving incident radiation thereon, and a chemically functional layer ( 9 ), such that electrostatic charge patterns may be formed in a predetermined manner upon the substrate to influence the movement of charged droplets in an emulsion ( 15 ) on the substrate. The chemically functional layer either provides a surface for chemical functionalization of the substrate or prevents access or reaction to the dielectric or photoconductive layer.
1. A substrate adapted for selective micron and nanometer scale deposition, the substrate having;
a support;
a conductive layer on the support;
a dielectric layer of a material which will hold an electrostatic charge, the dielectric layer disposed on the conductive layer; and
a continuous chemically functional layer on the dielectric layer, the chemically functional layer providing both a protective layer for the dielectric layer and a chemically reactive surface for compounds deposited on the surface;
wherein the chemically functional layer prevents liquids and the compounds deposited on the surface from accessing the dielectric layer; and
wherein the substrate is capable of having electrostatic charge patterns formed in a predetermined manner thereupon or therein.
2. A substrate as in claim 1 wherein the support is selected from the group comprising a metal, glass, ceramic, or polymeric material and the support is clear or opaque and flexible or rigid.
3. A substrate as in claim 1 wherein the conductive layer is combined with the support.
4. A substrate as in claim 1 wherein the conductive layer is a very thin layer and is transparent.
5. A substrate as in claim 1 wherein the conductive layer is vacuum-deposited onto the support.
6. A substrate as in claim 1 wherein the conductive layer is selected from the group comprising a sputtered layer of metal or indium tin oxide, or a carbon nano-tube layer.
7. A substrate as in claim 1 wherein the dielectric layer comprises a material selected from the group consisting of a glass, a polymeric resin and a methylmethacrylate (MMA).
8. A substrate as in claim 1 wherein the dielectric in the dielectric layer comprises a photoconductor.
9. A substrate as in claim 8 wherein the photoconductor is selected from the group comprising zinc oxide, cadmium sulphide, lead sulphide, lead selenide, amorphous selenium, doped selenium, alloys of selenium including selenium-tellurium, selenium-arsenic, organic photoconductive materials.
10. A substrate as in claim 1 wherein the chemically functional layer comprises a material selected from the group consisting of a silane polymer, silicon dioxide, silicon nitride (Si x N y ), titanium dioxide, organic titanates and zirconates, cross-linked or partially cross-linked epoxy novolac resins, polymerised oligomers, cross-linked resins, functionalised parylene (a polymer of di-para-xylyene), acrylates and methacrylates which may include functional groups, multi-functional acrylates and methacrylates, and monomers which have been crosslinked with a photoinitiator.
11. A substrate having;
a support;
a conductive layer on the support;
a photoconductive layer of a material which is adapted to have an electrostatic charge thereon selectively dissipated upon receiving incident radiation, the photoconductive layer disposed on the conductive layer; and
a continuous chemically functional layer on the photoconductive layer, the chemically functional layer providing both a protective layer for the photoconductive layer and a chemically reactive surface for compounds deposited on the surface;
wherein the chemically functional layer prevents liquids and the compounds deposited on the surface from accessing the photoconductive layer; and
wherein the substrate is capable of having electrostatic charge patterns formed in a selected array thereupon to influence the movement of charged droplets in a liquid medium on the substrate.
12. A substrate adapted for manufacture of DNA arrays, the substrate having;
a support;
a conductive layer on the support;
a photoconductive layer of a material which is adapted to have an electrostatic charge thereon dissipated upon receiving incident radiation, the photoconductive layer disposed on the conductive layer; and
a continuous chemically functional layer on the photoconductive layer, the chemically functional layer providing a protective layer for the photoconductive layer;
wherein the chemically functional layer prevents liquids and compounds deposited on the chemically functional layer from accessing the photoconductive layer; and
wherein the substrate is capable of having electrostatic charge patterns formed in a selected array thereupon to influence the movement of charged droplets in a liquid medium on the substrate;
the chemically functional layer comprising at least in part a chemically active material to which a molecule can be attached, the molecule being selected from the group consisting of a binder molecular and a binder molecule with at least one DNA oligomer joined thereto, whereby the substrate is capable of having a selected electric charge pattern generated thereupon by incident radiation to enable selective chemical de-protection of the binder molecule or the at least one DNA oligomer already joined to the binder molecule.
13. A substrate adapted for manufacture of DNA arrays, the substrate having;
a support;
a conductive layer on the support;
a photoconductive layer of a material which is adapted to have an electrostatic charge thereon selectively dissipated upon receiving incident radiation, the photoconductive layer disposed on the conductive layer; and
a continuous chemically functional layer on the photoconductive layer, the chemically functional layer providing a protective layer for the photoconductive layer;
wherein the chemically functional layer prevents liquids and compounds deposited on the chemically functional layer from accessing the photoconductive layer; and
wherein the substrate is capable of having electric charge patterns formed in a selected array thereupon to influence the movement of charged droplets in a medium on the substrate; the chemically functional layer providing a surface to which a binder molecule can be attached.
14. A substrate as in claim 9 wherein the organic photoconductive materials comprise polyvinylcarbazole (PVK) or complexes of polyvinylcarbazole sensitised with trinitrofluorenone.
15. A substrate as in claim 1 wherein the continuous chemically functional layer is disposed on substantially the entire dielectric layer.
16. A substrate as in claim 1 wherein the continuous chemically functional layer is a mono-molecular film.
17. A substrate as in claim 11 wherein the continuous chemically functional layer is disposed on substantially the entire photoconductive layer.
18. A substrate as in claim 11 wherein the continuous chemically functional layer is a mono-molecular film.
19. A substrate as in claim 12 wherein the continuous chemically functional layer is disposed on substantially the entire photoconductive layer.
20. A substrate as in claim 13 wherein the continuous chemically functional layer is a mono-molecular film.