Memory device

• US 20040159835A1
• Filed: 02/11/2004
• Published: 08/19/2004
• Est. Priority Date: 08/13/2001
• Status: Active Grant

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Advanced Micro Devices, Inc.
• Inventors: Krieger, Juri Heinrich, Yudanov, Nikolay Fedorovich
• Granted Patent: US 7,026,702 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: G11C 11/34 using semiconductor devices
• CPC Class Codes: G11C 11/5664 using organic memory material storage elements
• CPC Class Codes: G11C 13/0009 RRAM elements whose operation depends upon chemical change
• CPC Class Codes: G11C 13/0014 comprising cells based on organic memory material
• CPC Class Codes: G11C 13/0016 comprising polymers
• CPC Class Codes: G11C 13/0064 Verifying circuits or methods
• CPC Class Codes: G11C 13/0069 Writing or programming circuits or methods
• CPC Class Codes: G11C 13/04 using optical elements ; using other beam accessed elements, e.g. electron or ion beam
• CPC Class Codes: G11C 2213/11 Metal ion trapping, i.e. using memory material including cavities, pores or spaces in form of tunnels or channels wherein metal ions can be trapped but do not react and form an electro-deposit creating filaments or dendrites
• CPC Class Codes: G11C 2213/15 Current-voltage curve
• CPC Class Codes: G11C 2213/34 Material includes an oxide or a nitride
• CPC Class Codes: G11C 2213/35 Material including carbon, e.g. graphite, grapheme
• CPC Class Codes: G11C 2213/52 Structure characterized by the electrode material, shape, etc.
• CPC Class Codes: G11C 2213/56 Structure including two electrodes, a memory active layer and a so called passive or source or reservoir layer which is NOT an electrode, wherein the passive or source or reservoir layer is a source of ions which migrate afterwards in the memory active layer to be only trapped there, to form conductive filaments there or to react with the material of the memory active layer in redox way
• CPC Class Codes: G11C 2213/71 Three dimensional array
• CPC Class Codes: G11C 2213/77 Array wherein the memory element being directly connected to the bit lines and word lines without any access device being used
• CPC Class Codes: H10B 41/30 characterised by the memory core region
• CPC Class Codes: H10K 10/701 Organic molecular electronic devices
• CPC Class Codes: H10K 19/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic element specially adapted for rectifying, amplifying, oscillating or switching, covered by group H10K10/00
• CPC Class Codes: H10K 19/202 : Integrated devices comprising a common active layer
• CPC Class Codes: H10K 85/10 : Organic polymers or oligomers
• CPC Class Codes: H10K 85/111 : comprising aromatic, heteroaromatic, or aryl chains, e.g. polyaniline, polyphenylene or polyphenylene vinylene
• CPC Class Codes: H10K 85/113 : Heteroaromatic compounds comprising sulfur or selene, e.g. polythiophene
• CPC Class Codes: H10K 85/1135 : Polyethylene dioxythiophene [PEDOT]; Derivatives thereof
• CPC Class Codes: H10K 85/143 : Polyacetylene; Derivatives thereof
• CPC Class Codes: H10K 85/146 : poly N-vinylcarbazol; Derivatives thereof
• CPC Class Codes: H10K 85/30 : Coordination compounds
• CPC Class Codes: H10K 85/311 : Phthalocyanine
• CPC Class Codes: H10K 85/40 : Organosilicon compounds, e.g. TIPS pentacene
• CPC Class Codes: H10K 85/611 : Charge transfer complexes
• CPC Class Codes: H10K 85/649 : Aromatic compounds comprising a hetero atom
• CPC Class Codes: H10N 70/023 : by chemical vapor deposition, e.g. MOCVD, ALD
• CPC Class Codes: H10N 70/24 : based on migration or redistribution of ionic species, e.g. anions, vacancies
• CPC Class Codes: H10N 70/245 : the species being metal cations, e.g. programmable metallization cells
• CPC Class Codes: H10N 70/826 : adapted for essentially vertical current flow, e.g. sandwich or pillar type devices
• CPC Class Codes: H10N 70/8416 : adapted for supplying ionic species
• CPC Class Codes: H10N 70/881 : Switching materials
• CPC Class Codes: H10N 70/8822 : Sulfides, e.g. CuS
• CPC Class Codes: H10N 70/8825 : Selenides, e.g. GeSe
• CPC Class Codes: H10N 70/8828 : Tellurides, e.g. GeSbTe
• CPC Class Codes: H10N 70/883 : Oxides or nitrides
• CPC Class Codes: H10N 70/8833 : Binary metal oxides, e.g. TaOx
• CPC Class Codes: H10N 70/8836 : Complex metal oxides, e.g. perovskites, spinels

Abstract

Systems and methodologies for fabrication of a memory cell or array are disclosed. The memory cell employs a functional zone with passive and active layers. Such passive and active layers facilitate electron migration, and allow a plurality of states for the memory cell. A memory device formed in accordance with the disclosed methodology can include a top-electrode formed over the functional layer, which in turn over lays a lower conductive layer.

Claims

1. A memory device comprising:

a first electrode;

a functional media formed over the first electrode, a state of the functional media changes based on a migration of electrons or holes when subject to an external electric field or light radiation, the state indicative of information content; and

a second electrode formed over the functional media.

2. The memory device of claim 1, wherein the functional media comprises at least one of an active layer and a passive layer.

3. The memory device of claim 1, wherein the first electrode or the second electrode comprises at least one selected from the group of tungsten, silver, copper, titanium, chromium, germanium, gold, aluminum, magnesium, manganese, indium, iron, nickel, palladium, platinum, zinc, alloys thereof, indium-tin oxide, conductive oxides, polysilicon, doped amorphous silicon, metal silicides, and various copper composition alloys.

4. The memory device of claim 1, wherein the first electrode or the second electrode comprise at least one selected from the group of conducting polymers, semi-conducting polymers, PEDOT/PSS, polyaniline, polythiothene material, doped conducting organic polymers, doped semiconducting organic polymers, undoped conducting organic polymers, undoped semiconducting organic polymers, oligomers, monomers, conducting metal oxides, conducting metal nitrides, conducting metal silicides, semiconducting metal oxides, semiconducting metal nitrides, semiconducting metal silicides, and conductive organic polymers.

5. The memory device of claim 1, wherein the first electrode or the second electrode comprise amorphous carbon.

6. The memory device of claim 1, wherein the first electrode or the second electrode comprise at least one of optically transparent oxide and sulfide material.

7. The memory device of claim 2, wherein the active layer comprises at least one of an organic, metal organic, and non organic material.

8. The memory device of claim 2, wherein the active layer comprises at least one selected from the group of polydiphenylacetylene, poly(t-butyl)diphenylacetylene, poly(trifluoromethyl)diphenylacetylene, polybis-trifluoromethyl)acetylene, polybis(t-butyldiphenyl)acetylene, poly(trimethylsilyl)diphenylacetylene, poly(carbazole)diphenylacetylene, polydiacetylene, polyphenylacetylene, polypyridineacetylene, polymethoxyphenylacetylene, polymethylphenylacetylene, poly(t-butyl)phenylacetylene, polynitro-phenylacetylene, poly(trifluoromethyl)phenylacetylene, poly(trimethylsilyl)pheylacetylene, polydipyrrylmethane, polyindoqiunone, polydihydroxyindole, polytrihydroxyindole, furane-polydihydroxyindole, polyindoqiunone-2-carboxyl, polyindoqiunone monohydrate, polybenzobisthiazole, and poly(p-phenylene sulfide).

9. The memory device of claim 2, wherein the active layer comprises at least one of:

materials of a nitro group, materials of an amino group, cyclopentadienyl, dithiolane, metilcyclopentadienyl, fulvalenediyl, indenyl, fluorenyl, cyclobis(paraquart-p-phenylene), bipyridinium, phenothiazine, diazapyrenium, benzonitrile, benzonate, benzamide, carbazole, dibenzothiophene, nitrobenzene, aminobenzenesulfonate, and amonobenzanate.

10. The memory device of claim 2, wherein the active layer comprises molecular units with redox-active metals.

11. The memory device of claim 10, wherein the redox active metals comprise at least one of metallocenes complex and polypyridine metal complex.

12. The memory device of claim 2, wherein the active layer comprises at least one selected from the group of polyaniline, polythiophene, polypyrrole, polysilane, polystyrene, polyfuran, polyindole, polyazulene, polyphenylene, polypyridine, polybipyridine, polyphthalocyanine, polysexithiofene, poly(siliconoxohemiporphyrazine), poly(germaniumoxohemiporphyrazine), and poly(ethylenedioxythiophene).

13. The memory device of claim 2, wherein active layer comprises at least one selected from the group of aromatic hydrocarbons;

organic molecules with donor and acceptor properties, metallo-organic complexes;

porphyrin, phthalocyanine, and hexadecafluoro phthalocyanine.

14. The memory device of claim 13, wherein the organic molecules with donor acceptor properties comprises at least one selected from the group of N-Ethylcarbazole, tetrathiotetracene, tetrathiofulvalene, tetracyanoquinodimethane, tetracyanoethylene, cloranol, and dinitro-n phenyl.

15. The memory device of claim 13, wherein the metallo-organic complexes are selected from the group of bisdiphenylglyoxime, bisorthophenylenediimine, and tetraaza-tetramethylannulene.

16. The memory device of claim 2, wherein the active layer comprises organic material selected from the group comprising of polyacetylene, polyphenylacetylene, polydiphenylacetylene, polyaniline, poly(p-phenylene vinylene), polythiophene, polyporphyrins, porphyrinic macrocycles, thiol derivatized polyporphyrins, polymetallocenes, polyferrocenes, polyphthalocyanines, polyvinylenes, and polystiroles.

17. The memory device of claim 2, wherein the active layer comprises material selected from the group comprising of electric dipole elements, polymer ferroelectrics clusters, non-organic ferro-electrics, salts, alkalis, acids, and water molecules.

18. The memory device of claim 2, wherein the active layer comprises material that can dissociate in at least one of an electrical field and under light radiation.

19. The memory device of claim 18, wherein the material that can dissociate on anions that are selected from the group consisting of 1, Br, Cl, F, ClO₄, AlCl₄, PF₆, AsF₆, AsF₄, SO₃CF₃, BF₄, BCl₄, NO₃, POF₄, CN, SiF₃, SiF₆, SO₄, CH₃CO₂, C₆H₅CO₂, CH₃C₆H₄SO₃, CF₃SO₃, N(SO₃CF₃)₂, N(CF₃SO₂)(C₄F₉SO₂), N(C₄F₉SO₂)₂, alkylphosphate, organoborate, bis-(4-nitrophenil)sulfonilimide, and poly(styrene sulfonate)(polyanions).

20. The memory device of claim 18, wherein the material that can dissociate on cations that are selected from the group consisting of Li, Na, K, Rb, Cs, Ag, Ca, Mg, Zn, Fe, Cu, H, and NH₄.

21. The memory device of claim 1, wherein the functional media comprises porous dielectric material.

22. The memory device of claim 21, wherein the porous dielectric material is selected from the group consisting of Si, amorphous Si, silicon dioxide (SiO₂), aluminum oxide (Al₂O₃), copper oxide (Cu₂O), titanium dioxide (TiO₂), boron nitride (BN), vanadium oxide (V₂O₃), carbon tri-nitride (CN₃), ferroelectric materials and barium-strontium titanate ((Ba, Sr) TiO₃).

23. The memory device of claim 1, thicknesses of the first electrode and the second electrode being at least about 0.01 μ

m or at most about 10 μ

m.

24. The device of claim 2, the active layer having a thickness of at least about 0.001 μ

m or at most about 5 μ

m.

25. The device of claim 2, a thickness of the active layer is about 10 to about 500 times greater than a thickness of the passive layer.

26. A method of fabricating an organic memory device that operates based upon electron-hole movement through a passive layer and an active layer, comprising:

forming a first electrode on a substrate;

forming the passive layer on the first electrode;

forming the active layer on the passive layer; and

forming a second electrode on the active layer.

27. The method of claim 26 further comprising forming the active layer via a chemical vapor deposition process.

28. The method of claim 26 further comprising forming the active layer via a gas phase reaction process.

29. The method of claim 26, further comprising forming the active layer formed via a spin coating process or a liquid phase reaction process.

30. The method of claim 26, further comprising applying a first voltage to the first non-copper electrode and the second electrode, to set an impedance state of the organic memory device, the impedance state representing information content.

31. The method of claim 26, further comprising applying a second voltage to the first electrode and the second electrode to determine an impedance state of the memory device, the impedance state representing information content.

32. A system that operates an organic memory device comprising:

means for changing an impedance state of the organic memory device; and

means for containing information in the organic memory device based on the impedance state.