Stabilised cyclosiloxanes for use as precursors for low-dielectric constant thin films

• Main Authors: TIANNIU CHEN, CHONGYING XU, THOMAS H BAUM, ALEXANDER S. BOROVIK, RAVI K. LAXMAN
• Format: Patent
• Language: English
• Published: 02.03.2005
• Edition: 7
• Subjects: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAININGELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN,SULFUR, SELENIUM OR TELLURIUM; ADHESIVES; BASIC ELECTRIC ELEMENTS; CHEMICAL PAINT OR INK REMOVERS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING COMPOSITIONS, e.g. PAINTS, VARNISHES ORLACQUERS; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; COMPOSITIONS BASED THEREON; CORRECTING FLUIDS; DIFFUSION TREATMENT OF METALLIC MATERIAL; DYES; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; FILLING PASTES; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; INKS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; MISCELLANEOUS APPLICATIONS OF MATERIALS; MISCELLANEOUS COMPOSITIONS; NATURAL RESINS; ORGANIC CHEMISTRY; ORGANIC MACROMOLECULAR COMPOUNDS; PAINTS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; POLISHES; SEMICONDUCTOR DEVICES; SEPARATION; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; USE OF MATERIALS THEREFOR; WOODSTAINS

A stabilised siloxane dielectric precursor, for use in a chemical vapour deposition (CVD) process, dosed with a stabilising agent or agents selected from free radical inhibitors, end-capping agents or a mixture thereof. Preferred siloxane dielectric precursors are cyclosiloxanes such as polyhedral oligomeric silsesquioxanes (POSS), octamethylcyclotetrasiloxane (OMCTS), hexamethylcyclotetrasiloxane (HMCTS), tetramethylcyclotetrasiloxane (TMCTS) and mixtures thereof. Suitable end-capping agents are monofunctional silylating agents having a formula R R R SiX, wherein X is a reactive site and R -R are hydrogen, C1-C8 alkyl or C5-C12 aryl, preferably silyl-N-methylacetamides, naphthylphenylmethylsilanol (NPMS), trifluoropropyldimethylsilyl-N-methylacetamide (TFSA), bis(trimethylsilyloxy)methylsilane or hexamethyldisilazane. Suitable radical inhibitors include phenols such as butylated hydroxy toluene (BHT), hydroquinone or butylated hydroxyanisole (BHA), and diphenylamine. A process for stabilizing a cyclosiloxane dielectric precursor, optionally including azeotropic distillation and/or treatment with an absorbent bed material such as CaO, and a CVD process using the stabilised cyclosiloxane are also outlined.