Zeolite sol and method for preparing the same, composition for forming porous film, porous film and method for forming the same, interlevel insulator film, and semiconductor device

• US 20040091419A1
• Filed: 11/07/2003
• Published: 05/13/2004
• Est. Priority Date: 11/13/2002
• Status: Active Grant

• Current Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Shin-Etsu Chemical Company Limited
• Original Assignee: Matsushita Electric Industrial Company Limited (Panasonic Holdings Corporation), Shin-Etsu Chemical Company Limited
• Inventors: Nakagawa, Hideo, Sasago, Masaru, Ogihara, Tsutomu, Yagihashi, Fujio
• Granted Patent: US 7,244,657 B2
• Time in Patent Office: Days
• US Class Current: 423/702
• CPC Class Codes: C01B 39/04 using at least one organic template directing agent, e.g. an ionic quaternary ammonium compound or an aminated compound
• CPC Class Codes: H01L 21/02126 the material containing Si, O, and at least one of H, N, C, F, or other non-metal elements, e.g. SiOC, SiOC:H or SiONC
• CPC Class Codes: H01L 21/02203 the layer being porous
• CPC Class Codes: H01L 21/02216 the compound being a molecule comprising at least one silicon-oxygen bond and the compound having hydrogen or an organic group attached to the silicon or oxygen, e.g. a siloxane
• CPC Class Codes: H01L 21/02282 liquid deposition, e.g. spin-coating, sol-gel techniques, spray coating
• CPC Class Codes: H01L 21/31695 Deposition of porous oxides or porous glassy oxides or oxide based porous glass

Abstract

The present invention provides a zeolite sol which can be formed into a porous film that can be thinned to an intended thickness by a method used in the ordinary semiconductor process, that excels in dielectric properties, adhesion, film consistency and mechanical strength, and that can be easily thinned; a composition for film formation; a porous film and a method for forming the same; and a high-performing and highly reliable semiconductor device which contains this porous film inside. More specifically, the zeolite sol is prepared by hydrolyzing and decomposing a silane compound expressed by a general formula: Si(OR¹)₄ (wherein R¹ represents a straight-chain or branched alkyl group having 1 to 4 carbons, and when there is more than one R¹, the R¹s can be independent and the same as or different from each other) in a conventional coating solution for forming a porous film in the presence of a structure-directing agent and a basic catalyst; and then by heating the silane compound at a temperature of 75° C. or lower. A composition for forming a porous film which contains this zeolite sol is used.

Claims

1. A method for preparing a zeolite sol, comprising the steps of:

hydrolyzing and condensing in the presence of a structure-directing agent and a basic catalyst a silane compound expressed by a general formula (1);

Si (OR¹)₄ 

 

(1)

wherein R¹ represents a straight-chain or branched alkyl group having 1 to 4 carbons, and when there is more than one R¹, the R¹s may be independent and the same as or different from each other; and

heating the silane compound at a temperature of 75°

C. or lower.

2. The method for preparing a zeolite sol according to claim 1, wherein the structure-directing agent is a quaternary organic ammonium hydroxide expressed by a general formula (2):

(R²)₄N⁺OH⁻

 

 

(2)

wherein R² represents a straight-chain or branched alkyl group having 1 to 5 carbons, and may be independent and the same as or different from each other.

3. The method for preparing a zeolite sol according to claim 1 or claim 2, wherein the basic catalyst is a compound which is expressed by a general formula (3):

(R³)₃N 

 

(3)

wherein R³ represents a hydrogen atom, a straight-chain, branched, or cyclic alkyl group or aryl group having 1 to 20 carbons and may be independent and the same as or different from each other, and the hydrogen atom or atoms contained in the alkyl group or the aryl group may be substituted by a hydroxy group or an amino group;

or by a general formula (4);

(R⁴)_nX 

 

(4)

wherein R⁴ represents a hydrogen atom, a straight-chain, branched, or cyclic alkyl group or aryl group having 1 to 20 carbons, or a monovalent compound expressed by the general formula (3) and may be independent and the same as or different from each other, and the hydrogen atom or atoms contained in the alkyl group or the aryl group may be substituted by a hydroxy group or an amino group; and

n represents an integer of 0 to 3; and

X represents an n-valent heterocyclic compound containing a nitrogen atom.

4. The method for preparing a zeolite sol according to any one of claims 1 to 3, wherein the zeolite sol has an average particle diameter of 3 to 15 mm.

5. A zeolite sol prepared by the method according to any one of claim 1 to claim 4.

6. A composition for forming a porous film containing the zeolite sol according to claim 5.

7. A composition for forming a porous film which contains the zeolite sol according to claim 5 and a composition comprising a silicon-containing compound.

8. A method for preparing a composition for forming a porous film, comprising the step of mixing the zeolite sol according to claim 5 with a composition comprising a silicon-containing compound.

9. The composition for forming a porous film according to claim 7, wherein the silicon-containing compound is a silane compound polymer prepared by hydrolyzing and condensing at least one kind of silane compound.

10. The method for preparing a composition for forming a porous film according to claim 8, wherein the silicon-containing compound is a silane compound polymer prepared by hydrolyzing and condensing at least one kind of silane compound.

11. The composition for forming a porous film according to claim 9, wherein the zeolite sol is 0.0001 to about 30 parts by weight per 1 part by weight of the silane compound polymer.

12. The method for preparing a composition for forming a porous film according to claim 10, wherein the zeolite sol is 0.0001 to about 30 parts by weight per 1 part by weight of the silane compound polymer.

13. A porous film prepared by using the composition for forming a porous film according to claim 6 or claim 7.

14. An interlevel insulator film prepared by using the composition for forming a porous film according to claim 6 or claim 7.

15. A semiconductor device containing a porous film inside, the porous film being formed by using a zeolite sol having an average particle diameter of 3 to 15 nm, wherein the zeolite sol is prepared by hydrolyzing and condensing in the presence of a structure-directing agent and a basic catalyst a silane compound expressed by a general formula (1):

Si (OR¹)₄ 

 

(1)

wherein R¹ represents a straight-chain or branched alkyl group having 1 to 4 carbons, and when there is more than one R¹, the R¹s can be independent and the same as or different from each other, and then by heat-treating the silane compound at a temperature of 75°

C. or lower.

16. The semiconductor device according to claim 15, wherein the structure-directing agent is a quaternary organic ammonium hydroxide expressed by a general formula (2):

(R²)₄N⁺OH⁻

 

 

(2)

wherein R² represents a straight-chain or branched alkyl group having 1 to 5 carbons, and may be independent and the same as or different from each other.

17. The semiconductor device according to claim 15 or claim 16, wherein the basic catalyst is a compound which is expressed by a general formula (3):

(R³)₃N 

 

(3)

wherein R³ represents a hydrogen atom, a straight-chain, branched, or cyclic alkyl group or aryl group having 1 to 20 carbons and may be independent and the same as or different from each other, and the hydrogen atom or atoms contained in the alkyl group or the aryl group may be substituted by a hydroxy group or an amino group, or by a general formula (4);

(R⁴)_nX 

 

(4)

wherein R⁴ represents a hydrogen atom, a straight-chain, branched, or cyclic alkyl group or aryl group having 1 to 20 carbons, or a monovalent compound expressed by the general formula (3) and may be independent and the same as or different from each other, and the hydrogen atom or atoms contained in the alkyl group or the aryl group may be substituted by a hydroxy group or an amino group;

n represents an integer of 0 to 3; and

X represents an n-valent heterocyclic compound containing a nitrogen atom.

18. The semiconductor device according to any one of claim 15 to claim 17, wherein the porous film is present in an insulator film between metal interconnections in a same layer of multilayered interconnections, or in an interlevel insulator film between vertical metal interconnection layers.