Device based on partially oxidized porous silicon and method for its production

• US 20050233438A1
• Filed: 10/15/2004
• Published: 10/20/2005
• Est. Priority Date: 04/19/2002
• Status: Active Grant

• Current Assignee: Angle Europe Limited (ANGLE Plc)
• Original Assignee: Infineon Technologies AG
• Inventors: Haneder, Thomas, Lehmann, Volker, Martin, Alfred, Dertinger, Stephan, Fuchs, Karin, Fritz, Michaela, Marz, Reinhard
• Granted Patent: US 7,410,794 B2
• Time in Patent Office: Days
• US Class Current: 435/287.200
• CPC Class Codes: B01J 19/0046 Sequential or parallel reactions, e.g. for the synthesis of polypeptides or polynucleotides; Apparatus and devices for combinatorial chemistry or for making molecular arrays synthesis methods per se C40B50/00
• CPC Class Codes: B01J 2219/00286 Reactor vessels with top and bottom openings
• CPC Class Codes: B01J 2219/00497 Features relating to the solid phase supports
• CPC Class Codes: B01J 2219/00511 Walls of reactor vessels
• CPC Class Codes: B01J 2219/00576 fluorophore
• CPC Class Codes: B01J 2219/00585 Parallel processes
• CPC Class Codes: B01J 2219/00596 Solid-phase processes
• CPC Class Codes: B01J 2219/00605 the compounds being directly bound or immobilised to solid supports
• CPC Class Codes: B01J 2219/00612 the surface being inorganic
• CPC Class Codes: B01J 2219/00621 by physical means, e.g. trenches, raised areas
• CPC Class Codes: B01J 2219/00626 Covalent
• CPC Class Codes: B01J 2219/00659 Two-dimensional arrays
• CPC Class Codes: B01J 2219/00677 Ex-situ synthesis followed by deposition on the substrate
• CPC Class Codes: B01J 2219/00707 separated from the reactor apparatus
• CPC Class Codes: B01J 2219/00711 Light-directed synthesis
• CPC Class Codes: B01J 2219/00722 Nucleotides
• CPC Class Codes: B01J 2219/00725 Peptides
• CPC Class Codes: B01J 2219/00729 Peptide nucleic acids [PNA]
• CPC Class Codes: B01L 3/50857 using arrays or bundles of open capillaries for holding samples
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C30B 29/06 : Silicon
• CPC Class Codes: C30B 33/00 : After-treatment of single crystals or homogeneous polycrystalline material with defined structure C30B31/00 takes precedence
• CPC Class Codes: C40B 40/06 : Libraries containing nucleotides or polynucleotides, or derivatives thereof
• CPC Class Codes: C40B 40/10 : Libraries containing peptides or polypeptides, or derivatives thereof
• CPC Class Codes: C40B 60/14 : for creating libraries
• CPC Class Codes: G01N 33/54373 : involving physiochemical end-point determination, e.g. wave-guides, FETS, gratings

Abstract

Device having a flat macroporous support material made of silicon and having surfaces, a plurality of pores each having a diameter in a range of from 500 nm to 100 μm distributed over at least one surface region of the support material and extending from one surface through to the opposite surface of the support material, at least one region having one or more pores with SiO2 pore walls, and a frame of walls with a silicon core surrounding the at least one region and arranged essentially parallel to longitudinal axes of the pores and open towards the surfaces, wherein the silicon core merges into silicon dioxide over a cross section towards an outer side of the walls forming the frame.

Claims

1. A device comprising:

a flat macroporous support material made of silicon and having surfaces;

a plurality of pores each having a diameter in a range of from 500 nm to 100 μ

m distributed over at least one surface region of the support material and extending from one surface through to the opposite surface of the support material;

at least one region having one or more pores with SiO₂ pore walls; and

a frame of walls with a silicon core surrounding the at least one region and arranged essentially parallel to longitudinal axes of the pores and open towards the surfaces, wherein the silicon core merges into silicon dioxide over a cross section towards an outer side of the walls forming the frame.

2. The device according to claim 1, wherein the support material has a thickness between 100 to 5000 μ

m.

3. The device according to claim 1, wherein a pore density is in a range of from 10⁴ to 10⁸/cm².

4. The device according to claim 1, wherein the pores with SiO₂ pore walls are substantially square and the frame of walls with the silicon core is substantially square or rectangular in shape.

5. The device according to claim 1, wherein capture molecules selected from the group consisting of DNA, proteins, and ligands are covalently bound at least locally to at least one of the pores.

6. The device according to claim 5, wherein the capture molecules are oligonucleotide probes which are bound via terminal amino or thiol groups to linker molecules, which are in turn bound to the pores via covalent and/or ionic groups.

7. A method for producing the device according to claim 1, comprising the steps of:

(a) preparing the support material;

(b) producing blind holes having a depth less than a thickness of the support material by electrochemical etching into the one surface of the support material, such that a spacing of the blind holes provided in an otherwise substantially regular arrangement is locally increased to form inter-region transitions with an increased silicon wall thickness, wherein a thickness of the silicon walls between the inter-region transitions is greater than a thickness of the silicon walls inside the region by an amount of the increased blind-hole spacing;

(c) at least locally arranging a mask layer on the one surface of the support material and the surface of the blind holes produced in step (b);

(d) eroding the support material at least as far as the bottom of the blind holes in order to obtain pores which extend from the one surface through to the opposite surface of the support material;

(e) removing the mask layer; and

(f) subjecting the support material to a thermal oxidation such that, as a function of the silicon wall thickness, the regions with thinner silicon walls are fully oxidized whereas the silicon walls are not fully oxidized in the inter-region transitions with an increased wall thickness, so that a silicon core is left remaining in the walls.

8. The method according to claim 7, wherein the mask layer is formed of Si₃N₄.

9. The method according to claim 7, wherein the erosion in step (d) is carried out by etching with KOH or by a CMP process.

10. The method according to claim 7, wherein the pores produced in step (d) are widened or enlarged before the treatment in step (e).

11. The method according to claim 10, wherein Si(100) is used as the support material and the diameter of the pores produced in step (d) is widened by etching in KOH before the treatment in step (e) in order to obtain substantially square pores.

12. A method of detecting biochemical reactions and/or bindings for a study of enzymatic reactions, nucleic acid hybridizations, protein-protein interactions, and protein-ligand interactions using the device according to claim 1 as a basis for a sample support.

13. A method for controlling chemical or biochemical reactions or syntheses, comprising the steps of:

preparing a device according to claim 1;

introducing a synthesis substance into at least one of the pores of the support material; and

shining light into the pores in order to optically excite at least the synthesis substance.