Comb-shaped capacitor for use in integrated circuits

• US 6,410,955 B1
• Filed: 04/19/2001
• Issued: 06/25/2002
• Est. Priority Date: 04/19/2001
• Status: Expired due to Term

• Current Assignee: Micron Technology, Inc.
• Original Assignee: Micron Technology, Inc.
• Inventors: Baker, R. Jacob, Beigel, Kurt D.
• Primary Examiner(s): Christianson, Keith
• Assistant Examiner(s): Huynh, Yennhu B.
• Application Number:
  US09/838,526
• Time in Patent Office: 432 Days
• Field of Search: 257/307, 257/308, 257/905-908, 257/301-305, 361/230, 361/213, 361/229
• US Class Current: 257/307
• CPC Class Codes: G11C 11/15 using multiple magnetic layers G11C11/155 takes precedence
• CPC Class Codes: G11C 5/04 Supports for storage elements , e.g. memory modules; Mounting or fixing of storage elements on such supports
• CPC Class Codes: H01L 23/5223 Capacitor integral with wiring layers
• CPC Class Codes: H01L 27/0214 for internal polarisation, e.g. I2L
• CPC Class Codes: H01L 27/0805 Capacitors only
• CPC Class Codes: H01L 28/82 with an enlarged surface, e.g. formed by texturisation
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y10S 257/905 Plural dram cells share common contact or common trench
• CPC Class Codes: Y10S 257/906 Dram with capacitor electrodes used for accessing, e.g. bit line is capacitor plate
• CPC Class Codes: Y10S 257/908 Dram configuration with transistors and capacitors of pairs of cells along a straight line between adjacent bit lines

Abstract

A capacitor for use in integrated circuits comprises a layer of conductive material. The layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion are arranged in a predetermined pattern relative to one another to provide a maximum amount of capacitance per semiconductor die area.

Claims

1. A capacitor, comprising:

a substrate;

a layer of conductive material formed on the substrate, the layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion are arranged in a predetermined pattern relative to one another to provide a maximum amount of juxtaposed surface area between the first and second portions; and

a layer of insulation material disposed at least between the first and second portions.

2. The capacitor of claim 1, wherein the predetermined pattern is a substantially comb-like structure wherein the teeth of the combs of the first portion and the second portion are interleaved.

3. The capacitor of claim 2, wherein the teeth of each of the combs of the first and second portions have a selected height and length to provide a selected capacitance.

4. The capacitor of claim 1, wherein the predetermined pattern forms a substantially serpentine gap of a selected width between the first and second portions to provide a selected capacitance between the first and second portions.

5. A capacitor, comprising:

a substrate;

a layer of conductive material formed on the substrate, the layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion are arranged in a predetermined pattern relative to one another to provide a maximum amount of juxtaposed surface area;

a layer of insulation material disposed between and over the first and second portions;

a reference plate disposed on the layer of insulation material and over the first and second portions; and

at least one contact electrically connecting the reference plate to one of the first or second portions.

6. The capacitor of claim 5, wherein the at least one contact is a plug of conductive material disposed in a opening through the layer of insulation.

7. The capacitor of claim 6, wherein the plug is formed from one of tungsten, copper, aluminum or an alloy of tungsten, copper and aluminum.

8. A capacitor, comprising:

a substrate;

a layer of conductive material formed on the substrate, the layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion each have a substantially comb-like structure with a plurality of teeth, the teeth of the first portion and the second portion being interleaved and each tooth including a pair of sidewalls, each sidewall except an outside sidewall of an end tooth facing a sidewall of a tooth of the other portion to provide a maximum amount of juxtaposed surface area;

a layer of insulation material disposed between and over the first and second portions;

a reference plate disposed on the layer of insulation material and over the first and second portions; and

at least one contact electrically connecting the reference plate to one of the first or second portions.

9. The capacitor of claim 8, wherein the sidewall of each tooth has a selected height and length to provide a selected capacitance.

10. The capacitor of claim 8, further comprising a substantially serpentine gap of a selected width between the first and second portions to provide a selected capacitance between the first and second portions.

11. A capacitor, comprising:

a substrate;

a first reference plate of conductive material disposed on the substrate;

a first layer of insulation material covering the first reference plate;

a layer of conductive material formed on the first layer of insulation material, the layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion are arranged in a predetermined pattern relative to one another to provide a maximum amount of juxtaposed surface area;

a second layer of insulation material disposed between and over the first and second portions;

a second reference plate disposed on the second layer of insulation material and over the first and second portions; and

at least one contact electrically connecting at least one of the first and second reference plates to at least one of the first or second portions.

12. The capacitor of claim 11, wherein the at least one contact is a plug of conductive material disposed in a opening through at least one of the first or second layers of insulation.

13. The capacitor of claim 12, wherein the plug is formed from one of tungsten, copper, aluminum or an alloy of tungsten, copper and aluminum.

14. A capacitor, comprising:

a substrate;

a first reference plate of conductive material disposed on the substrate;

a first layer of insulation material covering the first reference plate;

a layer of conductive material formed on the substrate, the layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion each have a substantially comb-like structure with a plurality of teeth, the teeth of the first portion and the second portion being interleaved and each tooth including a pair of sidewalls, each sidewall except an outside sidewall of an end tooth facing a sidewall of a tooth of the other portion to provide a maximum amount of juxtaposed surface area;

a second layer of insulation material disposed between and over the first and second portions;

a second reference plate disposed on the second layer of insulation material and over the first and second portions; and

at least one contact electrically connecting at least one of the first and second reference plates to at least one of the first or second portions.

15. The capacitor of claim 14, wherein the sidewalls of each tooth has a selected height and length to provide a selected capacitance.

16. The capacitor of claim 14, wherein the interleaved comb-like structures form a substantially serpentine gap of a selected width between the first and second portions to provide a selected capacitance between the first and second portions.

17. A capacitor, comprising:

a substrate;

a first plurality of interconnected strips of a conductive material formed on the substrate;

a second plurality of interconnected strips of conductive material formed on the substrate, wherein the second plurality of strips are interleaved with the first plurality of strips; and

insulation material disposed between each of the first plurality of strips and each of the interleaved second plurality of strips.

18. The capacitor of claim 17, wherein each strip has a sidewall and wherein the first plurality of strips and the second plurality of strips are interleaved in a predetermined pattern to provide a maximum of juxtaposed sidewall surface area of the first plurality of strips and the second plurality of strips.

19. The capacitor of claim 17, wherein each strip has a sidewall of a selected height and length and wherein the first plurality of strips and the second plurality of strips are interleaved in a predetermined pattern to provide the maximum capacitance per selected area of the substrate.

20. A capacitor, comprising:

a first substantial comb-like structure of conductive material including a plurality of teeth; and

a second substantially comb-like structure of conductive material including a plurality of teeth, wherein the teeth of the second substantially comb-like structure are interleaved with the teeth of the first substantially comb-like structure, and wherein each tooth of the first and second comb-like structures have a pair of sidewalls, each sidewall having a selected surface area and each of the teeth of the first comb-like structure and the second comb-like structure being separated by a gap of a chosen width to provide a predetermined capacitance.

21. The capacitor of claim 20, wherein the first comb-like structure and the second comb-like structure are interleaved to provide a maximum amount of juxtaposed sidewall surface area between the teeth of the first and second comb-like structures.

22. A capacitor, comprising:

a first substantial comb-like structure of conductive material including a plurality of teeth;

a second substantially comb-like structure of conductive material including a plurality of teeth, wherein the teeth of the second substantially comb-like structure interleave the teeth of the first substantially comb-like structure, and wherein each tooth of the first and second comb-like structures have a pair of sidewalls, each sidewall having a selected surface area and each of the teeth of the first comb-like structure and the second comb-like structure being separated by a gap of a chosen width to provide a predetermined capacitance;

a reference plate of a conductive material disposed adjacent the first and second comb-like structures at a selected distance therefrom;

a layer of insulation material disposed between the reference plate and the first and second comb-like structures; and

at least one contact electrically connecting the reference plate and one of the first and second comb-like structures.

23. The capacitor of claim 22, wherein the at least one contact is formed through an opening formed in the layer of insulation and comprises at least one of tungsten, copper and aluminum.

24. A capacitor, comprising:

a first substantial comb-like structure of conductive material including a plurality of teeth; and

a second substantially comb-like structure of conductive material including a plurality of teeth, wherein each tooth of the first and second comb-like structures have a pair of sidewalls with a selected surface area and wherein the first comb-like structure and the second comb-like structure are interleaved to provide a maximum amount of juxtaposed sidewall surface area between the teeth of the first and second comb-like structures.

25. The capacitor of claim 24, wherein the first comb-like structure and the second comb-like structure are separated by a gap and wherein the width of the gap and the surface area of each of the sidewalls are selected to provide a predetermined capacitance.

26. A capacitor, comprising:

a first substantial comb-like structure of conductive material including a plurality of teeth;

a second substantially comb-like structure of conductive material including a plurality of teeth, wherein the teeth of the second substantially comb-like structure are interleaved with the teeth of the first substantially comb-like structure, and wherein each tooth of the first and second comb-like structures have a pair sidewalls, each sidewall having a selected surface area and each of the teeth of the first comb-like structure and the second comb-like structure being separated by a gap of a chosen width to provide a predetermined capacitance;

a first reference plate of a conductive material disposed on one side of the first and second comb-like structures facing the plurality of teeth at a selected distance therefrom;

a first layer of insulation material disposed between the first reference plate and the first and second comb-like structures;

a second reference plate of conductive material disposed on another side of the first and second comb-like structures facing the plurality of teeth at the selected distance;

a second layer of insulation material disposed between the second reference plate and the first and second comb-like structures; and

at least one contact electrically connecting at least one of the first and second reference plates to at least one of the first or second comb-like structures.

27. A capacitor, comprising:

a layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion are arranged in a predetermined pattern relative to one another to provide a maximum amount of capacitance per area; and

a layer of insulation material disposed at least between the first and second portions.

28. The capacitor of claim 27, wherein the layer of conductive material comprises tungsten.

29. The capacitor of claim 27, wherein the layer of conductive material comprises:

a first layer of metalization or polysilicon;

a layer of tungsten disposed on the layer of metalization or polysilicon; and

a second layer of metalization or polysilicon.

30. A capacitor, comprising:

a layer of conductive material, the layer of conductive material including at least a first portion and a second portion, wherein the first portion and the second portion are arranged in a predetermined pattern relative to one another to provide a selected amount of juxtaposed surface area between the first and second portions and the first and second portions being separated by a gap of a chosen width to provide a predetermined capacitance; and

a layer of insulation material disposed at least between the first and second portions.

31. A capacitor, comprising:

a first substantially comb-like structure of conductive material including a plurality of teeth; and

a second substantially comb-like structure of conductive material including a plurality of teeth, wherein each tooth of the first and second comb-like structures have a pair of sidewalls with a selected surface area and wherein the first comb-like structure and the second comb-like structure are interleaved to provide a maximum capacitance.

32. The capacitor of claim 31, wherein the first and second substantially comb-like structures each comprise tungsten.

33. The capacitor of claim 31, wherein the first and second substantially comb-like structures each comprise:

a first layer of metalization or polysilicon;

a layer of tungsten disposed on the layer of metalization or polysilicon; and

a second layer of metalization or polysilicon.