(12) United States Patent (10) Patent No.: US 6,469,123 B1 Lau Et Al

(12) United States Patent (10) Patent No.: US 6,469,123 B1 Lau Et Al

USOO6469 123B1 (12) United States Patent (10) Patent No.: US 6,469,123 B1 Lau et al. (45) Date of Patent: Oct. 22, 2002 (54) COMPOSITIONS AND METHODS FOR OTHER PUBLICATIONS THERMOSETTING MOLECULES IN &T ORGANIC COMPOSITIONS Reichert et al, Highly crosslinked polymers based on acetylene derivatives of tetraphenyladamantane”, 1994, (75) Inventors: Kreisler S. Lau, Sunnyvale; Feng Journal, Chem Abstract 121: 256441.* Quan Liu, Cupertino; Boris A. Yao et al., “Facile convergent route to molecular caltrops', Korolev, Emma Brouk, both of San 1999, Journal, Chem Abstract 130: 267486.* Jose; Ruslan Zherebin, Daly City, all Chen, et al. entitled, "Diamond Derivatives for Pharmaceu of CA (US); David Nalewajek, West tical Use' dated 1993. Seneca, NY (US) * cited by examiner (73) Assignee: Honeywell International Inc., Primary Examiner Duc Truong Morristown, NJ (US) (74) Attorney, Agent, or Firm-Sandra P. Thompson; Robert D. Fish; Rutan & Tucker, LLP (*) Notice: Subject to any disclaimer, the term of this patent is extended or adjusted under 35 (57) ABSTRACT U.S.C. 154(b) by 0 days. In a method of producing a low dielectric constant polymer, a thermosetting monomer is provided, wherein the thermo (21) Appl. No.: 09/618,945 Setting monomer has a cage compound or aryl core Structure, (22) Filed: Jul. 19, 2000 and a plurality of arms that are covalently bound to the cage e - 19 compound or core Structure. In a Subsequent Step, the (51) Int. Cl. ................................................ C08G 63/78 thermosetting monomer is incorporated into a polymer to (52) U.S. Cl. ......................... 528/86; 528/205; 528/207; form the low dielectric constant polymer, wherein the incor 528/208; 528/211; 525/132; 525/149; 525/152; poration into the polymer comprises a chemical reaction of 525/168; 525/177 a triple bond that is located in at least one of the arms. (58) Field of Search .......................... 528/86, 205, 207, Contemplated cage compounds and core Structures include 528/208, 211; 525/132, 149, 152, 168, adamantane, diamantane, Silicon, a phenyl group and a 177 Sexiphenylene group, while preferred arms include an arylene, a branched arylene, and an arylene ether. The (56) References Cited thermosetting monomerS may advantageously be employed to produce low-k dielectric material in electronic devices, U.S. PATENT DOCUMENTS and the dielectric constant of the polymer can be controlled 5,347,063 A 9/1994 Shen et al. ................. 585/352 by varying the Overall length of the arms. 5,458,709 A 10/1995 Kamezaki et al. ............ 156/89 5,744,399 A 4/1998 Rostoker et al. ............ 438/622 14 Claims, 9 Drawing Sheets C % - c C C C. ls) s X -- - r Cs -- --t C - , - U.S. Patent Oct. 22, 2002 Sheet 1 of 9 US 6,469,123 B1 U.S. Patent Oct. 22, 2002 Sheet 2 of 9 US 6,469,123 B1 FIG. 1C U.S. Patent Oct. 22, 2002 Sheet 3 of 9 US 6,469,123 B1 C Cc. FIG. 2A C K)-C=C-K)-C=C-(X-O C. ( C C ( ) ( ) ( ) ( ) ( ) O-K)-( FIG. 2B (y occocco ( ) C. U.S. Patent Oct. 22, 2002 Sheet 4 of 9 US 6,469,123 B1 FIG. 2C 4 (Icic- }}c-CH U.S. Patent Oct. 22, 2002 Sheet 5 of 9 US 6,469,123 B1 FIG. 2D U.S. Patent Oct. 22, 2002 Sheet 6 of 9 US 6,469,123 B1 Br s FIG. 3A U.S. Patent Oct. 22, 2002 Sheet 7 of 9 US 6,469,123 B1 OMe Ol Br O (1) --- ... of (C) OMe MeO (6) FIG. 3B U.S. Patent Oct. 22, 2002 Sheet 8 of 9 US 6,469,123 B1 O-C- n=1-3 | FIG. 3C U.S. Patent Oct. 22, 2002 Sheet 9 of 9 US 6,469,123 B1 -St in *O 2. O O --N *2.O C N S. N 1. s in US 6,469,123 B1 1 2 COMPOSITIONS AND METHODS FOR not Suitable for nanoporous materials where pores Smaller THERMOSETTING MOLECULES IN than 2 nm are desired. ORGANIC COMPOSITIONS To produce pores with a size Substantially Smaller than glass spheres, Rostoker et al. describe in U.S. Pat. No. FIELD OF THE INVENTION 5,744,399 the use of fullerenes as void carriers. Fullerenes The field of the invention is reduction of dielectric con are a form of carbon containing from 32 atoms to about 960 StantS. atoms, which are believed to have the Structure of a spherical geodesic dome, many of which are believed to occur natu BACKGROUND OF THE INVENTION rally. The inventors mix a matrix material with fullerenes, AS interconnectivity in integrated circuits increases and and cure the mixture to fabricate a nanoporous dielectric, the size of functional elements decreases, the dielectric wherein the fullerenes may be removed from the cured constant of insulator materials embedding the metallic con matrix. Although the pores obtained in this manner are ductor lines in integrated circuits becomes an increasingly generally very uniform in size, homogeneous distribution of important factor influencing the performance of the inte the void carriers still remains problematic. Moreover, both grated circuit. Insulator materials having low dielectric 15 Rostoker's and Kamezaki's methods require addition or constants (i.e., below 3.0) are especially desirable, because admixture of the Void carriers to a polymeric material, they typically allow faster Signal propagation, reduce thereby adding essential processing Steps and cost in the capacitive effects and croSS talk between conductor lines, fabrication of nanoporous materials. and lower Voltages to drive integrated circuits. Although various methods are known in the art to intro Since air has a dielectric constant of about 1.0, a major duce nanosized Voids into low dielectric constant material, goal is to reduce the dielectric constant of insulator materials all, or almost all of them have disadvantages. Thus, there is down towards a theoretical limit of 1, and several methods Still a need to provide improved compositions and methods are known in the art for including air into the insulator to introduce nanosized Voids in dielectric material. materials to reduce the dielectric constant of Such materials. 25 SUMMARY OF THE INVENTION In Some methods, air is introduced into the insulator material by generating nanosized Voids in a composition comprising The present invention is directed to a method of produc an adequately crosslinked thermostable matrix and a ther ing a low dielectric constant polymer. In one Step, a Star molabile (thermally decomposable) portion, which is either shaped thermosetting monomer having a core structure and Separately added to the thermostable matrix material a plurality of arms is provided, and in a Subsequent Step the (physical blending approach), or built-in into the matrix thermosetting monomer is incorporated into a polymer, material (chemical grafting approach). In general, the matrix wherein the incorporation into the polymer comprises a material is first crosslinked at a first temperature to obtain a reaction of a triple bond that is located in at least one arm. three-dimensional matrix, then the temperature is raised to a In one aspect of the inventive Subject matter, the core Second, higher temperature to thermolyze the thermolabile 35 Structure is a cage compound or aryl, and preferred arms are portion, and cured at a third, Still higher temperature to aryl, branched aryl or arylene ether. It is also preferred that anneal and Stabilize the desired nanoporous material that has where the core Structure is a cage compound, at least one of Voids corresponding in size and position to the size and the arms has a triple bond. Where the core structure is an aryl position of the thermolabile portion. compound, it is preferred that all of the arms have a triple In both the physical blending approach and the chemical 40 bond. Especially contemplated core Structures include grafting approach, nanoporous materials with desirable adamantane, diamantane, a phenyl, and a Sexiphenylene, and dielectric constants of about 2.5 and below may be achieved. especially contemplated arms include a tolanyl, a However, while there is typically only poor control over phenylethynylphenylethynylphenyl, a p-tolanylphenyl, a pore size and pore distribution in the physical blending 1,2-bis(phenylethynyl)phenyl, and a p-tolanylphenyl ether. approach, the chemical grafting approach frequently poses 45 In another aspect of the inventive Subject matter, the Significant challenges in the Synthesis of the polymers and incorporation of the thermosetting monomer includes a prepolymers and inclusion of various reactive groups (e.g., reaction on more than one triple bond, preferably on three to enable cross-linking, addition of thermolabile groups, triple bonds located on three arms, and more preferably on etc.) into the polymers and prepolymers. Moreover, the all triple bonds located in all arms. In particularly preferred chemical nature of both the thermolabile portion and ther 50 aspects of the inventive Subject matter, the incorporation mostable matrix generally limits processing temperatures to takes place without participation of an additional molecule relatively narrow windows which must distinguish the and preferably comprises a cyclo-addition reaction. crosslinking (cure) temperature, thermolysis temperature While it is generally contemplated that the thermosetting and glass transition temperature, thereby significantly lim monomer is incorporated in a backbone of a polymer, other iting the choice of available materials. 55 positions including the termini and Side chains are also In other methods, air or other gas (i.e. voids) is introduced appropriate. Preferred polymers include poly(arylene ethers) into the insulator material by incorporation of hollow, nano and polymers comprising, or consisting of contemplated sized Spheres in the matrix material, whereby the nanosized thermosetting monomers. It is especially contemplated that Spheres acts as a “void carriers', which may or may not be by increasing the length of the arms of the thermosetting removed from the matrix material.

View Full Text

Details

  • File Type
    pdf
  • Upload Time
    -
  • Content Languages
    English
  • Upload User
    Anonymous/Not logged-in
  • File Pages
    23 Page
  • File Size
    -

Download

Channel Download Status
Express Download Enable

Copyright

We respect the copyrights and intellectual property rights of all users. All uploaded documents are either original works of the uploader or authorized works of the rightful owners.

  • Not to be reproduced or distributed without explicit permission.
  • Not used for commercial purposes outside of approved use cases.
  • Not used to infringe on the rights of the original creators.
  • If you believe any content infringes your copyright, please contact us immediately.

Support

For help with questions, suggestions, or problems, please contact us