System for storing and retrieving information at the molecular level

• US 4,032,901 A
• Filed: 06/04/1975
• Issued: 06/28/1977
• Est. Priority Date: 02/12/1975
• Status: Expired due to Term

• Current Assignee: Cyrus Levinthal
• Original Assignee: Cyrus Levinthal
• Inventors: Levinthal, Cyrus
• Primary Examiner(s): Fears, Terrell W.
• Application Number:
  US05/583,554
• Time in Patent Office: 755 Days
• Field of Search: 340/173 NI
• US Class Current: 365/118
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G03C 1/731 Biological compounds
• CPC Class Codes: G03C 1/733 with macromolecular compounds as photosensitive substances, e.g. photochromic photodegradable or photocrosslinkable compositions G03F7/004
• CPC Class Codes: G11B 11/005 with reproducing by using non-optical beam of radiation or particles, e.g. electrons, directly interacting with the memorised information G11B11/007 takes precedence
• CPC Class Codes: G11B 9/10 using electron beam; Record carriers therefor G11B9/08 takes precedence see provisional also G11B11/03
• CPC Class Codes: G11C 11/23 using electrostatic storage on a common layer, e.g. Forrester-Haeff tubes or William tubesG11C11/22 takes precedence
• CPC Class Codes: G11C 13/0014 comprising cells based on organic memory material
• CPC Class Codes: G11C 13/048 using other optical storage elements
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2924/01019 Potassium [K]
• CPC Class Codes: H01L 2924/01078 Platinum [Pt]
• CPC Class Codes: H01L 2924/01079 Gold [Au]

Abstract

Disclosed is a system for retrievably storing information in a storage medium comprising a laterally extending layer of separate particles each of which has a size of several hundred Angstroms or less. The individual particles are up to approximately the size of protein molecules or virus particles and can, in fact, be single biological macromolecules, single virus particles, single polystyrene latex particles or other particles or aggregates of equivalent size. The particles may form a monolayer, or they may form a thicker slab as long as the slab surface is smooth compared to the size of a region of the slab used for the storage of a single bit of information. Small regions of this laterally extending layer or its surface, with lateral dimensions of a few thousand Angstroms or less, typically 1000A or less, can be selectively modified by a narrowly focused electron beam without substantially affecting adjacent regions, to thereby store (write in) information as a pattern of modified particles. After the slab surface has been so modified, it can be stabilized by depositing thereon a thin metallic film, and the stored information can be read out by a detecting electron beam.

Claims

1. An information storage medium comprising:

a substantially continuous layer of particles comprising an array of bit storage units, each bit storage unit being less than a few thousand Angstroms in size and each pair of adjacent bit storage units being spaced from each other by no more than up to a few thousand Angstroms, each unit comprising several particles of a material modifiable when irradiated by a focused electron beam without thereby modifying bit storage units adjacent thereto, and each bit storage unit storing one bit of information; and

means for supporting the layer of particles and the bit storage units thereof.

2. An information storage medium as in claim 1 wherein each of the particles comprising a bit storage unit is selected from the group consisting of:

a single organic molecule, a single virus, a single organic molecule having an insulator material cap attached thereto, a single virus having an insulator material cap attached thereto, a larger and a smaller organic molecule attached to each other, an inorganic molecule, an aggregate which is partly organic and partly inorganic, a larger and a smaller virus attached to each other, an insulator region in the interstitial space between adjacent particles on the surface of an extended layer, a plastic particle, and a region of material formed of subparticles which are substantially smaller in size than a unit.

3. An information storage medium comprising a support and an extended layer of bit storage units on said support, each unit being a few thousand Angstroms or less in size, said layer comprising units in a first state and units in a second state, and means disposed at each transition between units and having a defined response to irradiation by an electron beam, the defined response of the means at a transition between a unit in the first state and an adjacent unit in a second state being different than the defined response of the means at a transition between two adjacent units which are in the same state.

4. An information storage medium comprising a layer of bit storage units and a metallic layer overlaying the storage units, each unit being of the order of thousands or Angstroms of less in size, wherein the metallic layer adjacent one or more selected units of the layer of bit storage units has a first selected orientation with respect to the layer of bit storage units and the metallic layer adjacent the remaining units of the layer of bit storage units has a second selected orientation with respect to the layer of bit storage units, said first and second selected metallic layer orientations being substantially different from each other and causing the respective bit storage units to have a substantially different response to an irradiating electron beam.

5. An information storage medium comprising an extended, substantially continuous layer comprising a plurality of units arranged side-by-side along the layer, each unit being a few thousand Angstroms or less in size, with one or more selected units being substantially different from the remaining lattice units in their response to selected electron radiation, wherein said selected units are substantially identical to each other in said response and the remaining units are substantially identical to each other in said response but are different in said response from said response from said selected units.

6. An information storage medium comprising a plurality of bit storage units, each unit being a few thousand Angstroms or less in size, each pair of adjacent units being separated from each other by a distance of a few thousand Angstroms or less, each unit comprising several particles, and a reference grid separating multiunit parts of the layer from each other and formed of a material whose electron beam response is substantially different from that of at least a portion of the storage units.

7. An information storage system comprising:

a storage medium comprising a substantially continuous support and a lattice of bit storage units disposed on the support, each unit being a few thousand Angstroms or less in size; and

means for selectively permanently modifying individual units of the lattice, to thereby store information as a pattern of modified lattice units.

8. A system as in claim 7 including means for stabilizing the storage medium after modifying selected units thereof by depositing a metallic layer on the storage units, wherein the metallic layer portion adjacent a modified unit differs from the metallic layer portion adjacent an unmodified unit.

9. An information storage system comprising:

a storage medium comprising a substantially continuous support, a thin layer disposed on said support and comprising a lattice of bit storage units, each unit being a few thousand Angstroms or less in size and comprising several particles, with selected units having electron beam response which is substantially different from that of the remaining units; and

means for detecting and identifying said selected units.

10. A memory storage device comprising a wire grid with a polymer layer disposed on its top surface and extending into its interstices said polymer comprising a backbone of monomers chemically bound through functionally reactive groups thereon to macromolecular particles which are modifiable when irradiated with a focussed electron beam, said macromolecular particles each having a diameter of from about 50 to 300 Angstrom units and selected so that the modification of one particle does not substantially affect particles adjacent thereto.

11. A method of preparing a memory storage device which comprises:

coating a wire grid with a polymer layer, said polymer being comprised of monomer having functionally reactive groups; and

chemically combining said polymer through said reactive groups with macromolecular particles having a diameter of from about 50 to 300 Angstrom units, modifiable when irradiated with a focussed electron beam, and selected so that the modification of one particle does not substantially affect particles adjacent thereto.