3m Innovative Properties Company

Ankit Mahajan

Mikhail L Pekurovsky

Saagar A Shah

Kara A Meyers

Kayla C Niccum

Thomas J Metzler

Teresa M Goeddel

Matthew R D Smith

Jeremy K Larsen

Jonathan W Kemling

Nicholas T Gabriel

Roger W Barton

Gino L Pitera

Matthew S Stay

Joseph B Eckel

Shawn C Dodds

Graham M Clarke

Lyudmila A Pekurovsky

Christopher G Walker

Thomas P Klun

Richard John Pokorny

Ravi Palaniswamy

Jessica Chiu

Daniel J Theis

Ann M Gilman

Benjamin R Coonce

David J Rowe

Chad M Amb

David C Mercord

James Zhu

James F Poch

Richard C Webb

Jae Yong Lee

Daniel B Taylor

Pranati Mondkar

Donato G Caraig

Joseph E Hernandez

A method comprises: providing a layer of curable adhesive material () on a substrate (); forming a pattern of microstructures () on the layer of curable adhesive material (); curing a first region () of the layer of curable adhesive material () at a first level and a second region () of the layer of curable adhesive material () at a second level greater than the first level; providing a solid circuit die () to directly attach to a major surface of the first region () of the layer of curable adhesive material (); and further curing the first region () of the layer of curable adhesive material () to anchor the solid circuit die () on the first region () by forming an adhesive bond therebetween. The pattern of microstructures () may include one or more microchannels (), the method further comprising forming one or more electrically conductive traces in the microchannels (), in particular, by flow of a conductive particle containing liquid () by a capillary force and, optionally, under pressure. The at least one microchannel () may extend from the second region () to the first region () and have a portion beneath the solid circuit die (). The solid circuit die () may have at least one edge disposed within a periphery of the first region () with a gap therebetween. The solid circuit die () may have at least one contact pad () on a bottom surface thereof, wherein the at least one contact pad () may be in direct contact with at least one of the electrically conductive traces in the microchannels (). Forming the pattern of microstructures () may comprise contacting a major surface of a stamp () to the layer of curable adhesive material (), the major surface having a pattern of raised features () thereon. The curable adhesive material () may be cured by an actinic light source such as an ultraviolet (UV) light source ('), wherein a mask may be provided to at least partially block the first region () of the layer of curable adhesive material () from the cure. The stamp () may be positioned in contact with the curable adhesive material () to replicate the pattern of raised features () to form the microstructures () while the curable adhesive material () is selectively cured by the actinic light source such as the ultraviolet (UV) light source (). The first region () of the layer of curable adhesive material () may be cured at the first level to allow a bottom surface of the solid circuit die () to be fluidly-sealed by the major surface of the first region (). The second region of the layer of curable adhesive material () may be cured at the second level such that the second region () is fully cured. The further curing may be any suitable curing such as thermal curing, radiation curing (e.g., by actinic radiation, such as ultraviolet (UV) radiation) or self-curing at room temperature without using a thermal or radiation curing source.

Circuits including micropatterns and using partial curing to adhere dies

A method includes placing an electronic device on a pliable mating surface on a major surface of a mold such that at least one contact pad on the electronic device presses against the pliable mating surface. The pliable mating surface is on a microstructure in an arrangement of microstructures on the major surface of the mold. A liquid encapsulant material is applied over the electronic device and the major surface of the mold, and then hardened to form a carrier for the electronic device. The mold and the carrier are separated such that the microstructures on the mold form a corresponding arrangement of microchannels in the carrier, and at least one contact pad on the electronic device is exposed in a microchannel in the arrangement of microchannels. A conductive particle-containing liquid is deposited in the microchannel, which directly contacts the contact pad exposed in the microchannel.

Methods for registration of circuit dies and electrical interconnects

A pattern of microchannels is formed on a major surface of a substrate on the side opposite an adhesive surface thereof. Through holes extend through the substrate and are connected to the pattern of microchannels. Solid circuit dies are adhesively bonded to the adhesive surface of the substrate. The contact pads of the solid circuit dies at least partially overlie and face the through holes. Electrically conductive channel traces are formed to electrically connect to the solid circuit dies via the through holes.

Methods and devices using microchannels for interconnections

Devices including electrical connections to embedded electronic components and methods of making the same are provided. The devices include a flexible electronic component buried inside a substrate. The free end of the flexible electronic component can be extracted to stick out of the major plane of the substrate as a projecting contact.

Electrical connections to embedded electronic components

An article includes a solid circuit die on a first major surface of a substrate, wherein the solid circuit die includes an arrangement of contact pads, and wherein at least a portion of the contact pads in the arrangement of contact pads are at least partially exposed on the first major surface of the substrate to provide an arrangement of exposed contact pads; a guide layer including an arrangement of microchannels, wherein the guide layer contacts the first major surface of the substrate such that at least some microchannels in the arrangement of microchannels overlie the at least some exposed contact pads in the arrangement of exposed contact pads; and a conductive particle-containing liquid in at least some of the microchannels. Other articles and methods of manufacturing the articles are described.

Flexible circuits on soft substrates

A method for manufacturing an electronic device includes providing a substrate with a first major surface having a microchannel, wherein the microchannel has a first end and a second end; dispensing a conductive liquid in the microchannel to cause the conductive liquid to move, primarily by capillary pressure, in a first direction toward the first end of the microchannel and in a second direction toward the second end of the microchannel; and solidifying the conductive liquid to form an electrically conductive trace electrically connecting a first electronic device at the first end of the microchannel to a second electronic device at the second end of the microchannel.

Forming electrical interconnections using capillary microfluidics

Flexible electrical connectors are provided to electrically connect electronic devices. The flexible electrical connector includes a removable adhesive tape strip having an adhesive surface thereof and an electrically conductive trace disposed on the adhesive tape strip. The flexible electrical connector engages an electronic device to form an electrical contact where the adhesive tape strip has an adhesive surface removably adhesively bonded to the substrate of the electronic device to at least partially cover the electrical contact.

Removable electrical connectors and devices

A bonded abrasive wheel is disclosed comprising a plurality of abrasive particles disposed in a binder, a first grinding surface, a second surface opposing the first grinding surface, and an outer circumference. The wheel comprises a rotational axis extending through a central hub and a circuit configured as a Radio Frequency Identification (RFID) unit coupled to the abrasive wheel. The circuit comprises an antenna configured to communicate with one or more external devices and comprising a first end and a second end, wherein antenna has a radius of curvature about an axis along at least a portion thereof such that the first end is disposed adjacent to but is spaced from the second end, and an integrated circuit (IC) operably coupled to the antenna and configured to store at least a first data.

Embedded electronic circuit in grinding wheels and methods of embedding

Flexible devices including conductive traces with enhanced stretchability, and methods of making and using the same are provided. The circuit die is disposed on a flexible substrate. Electrically conductive traces are formed in channels on the flexible substrate to electrically contact with contact pads of the circuit die. A first polymer liquid flows in the channels to cover a free surface of the traces. The circuit die can also be surrounded by a curing product of a second polymer liquid.

Flexible device including conductive traces with enhanced stretchability

Electronic devices including a layer of polymeric material and solid semiconductor dies partially embedded in the layer are provided. The dies have first ends projecting away from the first major surface of the layer. The electronic devices can be formed by sinking the first ends of the dies into a major surface of a liner. A flowable polymeric material is filled into the space between the dies and solidified to form the layer of polymeric material. The first ends of the dies are exposed by delaminating the liner from the first ends of the dies. Electrical conductors are provided on the layer to connect the first ends of the dies.

Electronic devices including solid semiconductor dies

Processes for automatic registration between a solid circuit die and electrically conductive interconnects, and articles or devices made by the same are provided. The solid circuit die is disposed on a substrate with contact pads aligned with channels on the substrate. Electrically conductive traces are formed by flowing a conductive liquid in the channels toward the contact pads to obtain the automatic registration.

Automatic registration between circuit dies and interconnects

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Cupertino, CA, United States of America

Ankit Mahajan