Dow Corning Corporation

Keith W Michael

Loren A Haluska

Robert Charles Camilletti

Leo Tarhay

Udo C Pernisz

Clayton R Bearinger

Mark Jon Loboda

Grish Chandra

David S Ballance

Donald Taylor Liles

Howard M Bank

Ronald H Baney

Carl J Bilgrien

Jack S Kilby

Sudarsanan Varaprath

Kristen A Scheibert

Marie N Eckstein

Cathryn Marie Haines

Liberty B Shelton

Michael Dean Little

Alexander Brian Currie

Diana Kay Deese

Alvin L Moore

Sarah S Snow

Forrest O Stark

The instant invention pertains to a multi-layer tamper proof electronic coating wherein the first layer is a protecting layer produced from a preceramic silicon containing material and at least one filler. The second layer is a resin sealer coat produced from a sealer resin selected from the group consisting of colloidal inorganic-based siloxane resins, benzocyclobutene based resins, polyimide polymers, siloxane polyimides and parylenes. An optional third layer is a cap coating layer selected from SiO.sub.2 coating, SiO.sub.2 /ceramic oxide coating, silicon containing coatings, silicon carbon containing coatings, silicon nitrogen containing coatings, silicon oxygen nitrogen coatings, silicon nitrogen carbon containing coatings and/or diamond like coatings. An optional fourth layer is a resin overcoat produced from an overcoat resin selected from the group consisting of colloidal inorganic-based siloxane resins, benzocyclobutene based resins, polyimide polymers, siloxane polyimides, parylenes, photoresist polymers, siloxane room temperature vulcanizable compositions, or other organic polymer. The use of the multi-layer coating on the electronic device results in an electronic device that is resistant to analytical techniques such as ozone, UV-ozone, gaseous free radicals and ions, vapor or liquid borne reactive species, plasma, abrasion, radiation, light, wet etching and others; moisture; chemicals and other environmental contaminants; shock and erosion, delamination and/or separation.

Electronic coatings

Disclosed is a method of forming tamper-proof coatings on electronic devices. The method comprises applying a coating of a silica precursor resin and a filler onto the electronic device, wherein the filler is one which reacts in an oxidizing atmosphere to liberate enough heat to damage the electronic device. The coated electronic device is then heated at a temperature sufficient to convert the silica precursor resin to a silica containing ceramic matrix.

Tamper-proof electronic coatings

This invention pertains to a method of forming a coating on an electronic substrate and to the electronic substrates coated thereby. The method comprises applying on the electronic substrate a coating composition comprising an aqueous alkanol dispersion of colloidal silica and partial condensate of RSi(OH).sub.3 where R is selected from the group consisting of an alkyl radical having from 1 to 3 carbon atoms, the vinyl radical, the 3,3,3-trifluoropropyl radical, the gamma-glycidoxypropyl radical and the gamma-methacryloxypropyl radical with the provision that at least 70% of the R radicals are methyl, and thereafter ceramifying the coating by heating at a temperature of about 200.degree. C. to 1000.degree. C. The use of the coating composition comprising an aqueous alkanol dispersion of colloidal silica and partial condensate of RSi(OH).sub.3 allows for the formation of thick planarizing coatings on the electronic substrate.

Thick ceramic coatings for electronic devices

This invention relates to integrated circuits which are protected from the environment. Such circuits are hermetically sealed by applying additional ceramic layers to the primary passivation.

Hermetic protection for integrated circuits

Disclosed is the use of silicon carbide as a barrier layer to prevent the diffusion of metal atoms between adjacent conductors separated by a dielectric material. This advancement allows for the use of low resistivity metals and low dielectric constant dielectric layers in integrated circuits and wiring boards.

Silicon carbide metal diffusion barrier layer

The present invention relates to a ceramic coating composition comprising a preceramic material such as silicon oxide precursors, silicon carbonitride precursors, silicon carbide precursors, and silicon nitride precursors and a flux material such as B.sub.2 O.sub.3, PbO.sub.2, P.sub.2 O.sub.5, and Bi.sub.2 O.sub.3. The present invention also relates to a substrate such as an electronic device having said coating applied and ceramified thereon.

A silica-containing coating is formed on an electronic substrate by applying a polycarbosilane on the substrate and converting it to a silica-containing material by heating in an oxidizing environment. The resultant thick planarizing coatings are useful as protective coatings and dielectric inner layers.

Coating electronic substrates with silica derived from polycarbosilane

A method of forming a protective covering on an electronic or microelectronic device to prevent inspection. A first silica-containing ceramic layer is applied to the surface of the device to planarize its surface. A second silicon carbide coating layer is applied to the surface of the first silica-containing ceramic layer to form a hermetic barrier. A third porous silica-containing ceramic layer is formed on the surface of the second silicon carbide coating layer. The third porous silica-containing ceramic layer is impregnated with an opaque material or filler. A fourth metal layer or metal pattern is applied over the third opaque porous silica-containing ceramic layer. The fourth metal layer or pattern is then coated with a fifth layer similar to the third opaque porous silica-containing ceramic layer.

Multilayer coating for microelectronic devices

The present invention relates to a method of forming coatings on electronic substrates and the substrates coated thereby. The method comprises applying a coating comprising hydrogen silsesquioxane resin and a polysilazane on a substrate and heating the coated substrate at a temperature sufficient to convert the resins to ceramics.

Electronic coating materials using mixed polymers

Thick opaque ceramic coatings are used to protect delicate microelectronic devices against excited energy sources, radiation, light, abrasion, and wet etching techniques. The thick opaque ceramic coating are prepared from a mixture containing phosphoric anhydride, i.e., phosphorous pentoxide (P.sub.2 O.sub.5), and a pre-ceramic silicon-containing material. It is preferred to also include tungsten carbide (WC) and tungsten metal (W) in the coating mixture. The coating is pyrolyzed to form a ceramic SiO.sub.2 containing coating. A second coating of plasma enhanced chemical vapor deposited (PECVD) silicon carbide (SiC), diamond, or silicon nitride (Si.sub.3 N.sub.4), can be applied over the thick opaque ceramic coating to provide hermeticity. These coatings are useful on patterned wafers, electronic devices, and electronic substrates. The thick opaque ceramic coating is unique because it is resistant to etching using wet chemicals, i.e., acids such as H.sub.3 PO.sub.4 and H.sub.2 SO.sub.4, or bases.

Thick opaque ceramic coatings

A method for forming a cap on an electronic device to prevent inspection. First, a silica-containing ceramic is applied to the surface the electronic device to planarize the surface. Next, a silicon carbide coating is applied to the surface of the silica containing ceramic to form a hermetic barrier. A layer of porous silica-containing ceramic is then formed on the surface of the silicon carbide coating. Finally, the porous silica-containing ceramic is impregnated with an opaque material.

Protective electronic coating

Disclosed is a method of forming tamper-proof coatings on electronic devices. The method comprises applying a coating of a silica precursor resin and an inorganic salt onto the electronic device, wherein the inorganic salt is one which reacts with a wet etch to yield an acid or base that damages the electronic device. The coated electronic device is then heated at a temperature sufficient to convert the silica precursor resin to a silica containing ceramic matrix.

Thick opaque ceramic coatings are used to protect delicate microelectronic devices against excited energy sources, radiation, light, abrasion, and wet etching techniques. The thick opaque ceramic coating are prepared from a mixture containing tungsten carbide (WC), tungsten metal (W), and phosphoric anhydride, i.e., phosphorous pentoxide (P.sub.2 O.sub.5), carried in an aqueous alkanol dispersion of colloidal silica and partial condensate of methylsilanetriol. The coating is pyrolyzed to form a ceramic SiO.sub.2 containing coating. A second coating of plasma enhanced chemical vapor deposited (PECVD) silicon carbide (SiC), diamond, or silicon nitride (Si.sub.3 N.sub.4), can be applied over the thick opaque ceramic coating to provide hermeticity. These coatings are useful on patterned wafers, electronic devices, and electronic substrates. The thick opaque ceramic coating is unique because the methyl silsesquioxane resin is resistant to etching using wet chemicals, i.e., acids such as H.sub.3 PO.sub.4 and H.sub.2 SO.sub.4, or bases.

Opaque ceramic coatings

The instant invention pertains to a multi-layer tamper proof electronic coating wherein the first layer is a protecting layer produced from preceramic silicon containing material and at least one filler. The second layer is a resin sealer coat produced from a sealer resin selected from the group consisting of colloidal inorganic-based siloxane resins, benzocyclobutene based resins, polyimide polymers, siloxane polyimides and parylenes. An optional third layer is a cap coating layer selected from SiO.sub.2 coating, SiO.sub.2 /ceramic oxide coating, silicon containing coatings, silicon carbon containing coatings, silicon nitrogen containing coatings, silicon oxygen nitrogen coatings, silicon nitrogen carbon containing coatings and/or diamond like coatings. An optional fourth layer is a resin overcoat produced from an overcoat resin selected from the group consisting of colloidal inorganic-based siloxane resins, benzocyclobutene based resins, polyimide polymers, siloxane polyimides, parylenes, photoresist polymers, siloxane room temperature vulcanizable compositions, or other organic polymer. The use of the multi-layer coating on the electronic device results in an electronic device that is resistant to analytical techniques such as ozone, UV-ozone, gaseous free radicals and ions, vapor or liquid borne reactive species, plasma, abrasion, radiation, light, wet etching and others; moisture; chemicals and other environmental contaminants; shock and erosion, delamination and/or separation.

Disclosed are compositions which can be used to form tamper-proof coatings on electronic devices. These compositions contain a silica precursor resin and a filler which reacts in an oxidizing atmosphere to liberate heat. Such compositions form coatings which, when oxidized by techniques such as plasma etching, wet etching, or cross-sectioning, liberate heat which causes destruction of the underlying substrate and, thus, inhibits further examination.

Growing community of inventors

Midland, MI, United States of America

Keith W Michael