# US 2021/0243894 A1 · Selective transfer of micro devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0243894 A1 - Document ID: US20210243894A1 - Status: Published application - Kind: A1 - Application number: 17/222,506 - Filed: 2021-04-05 - Published: 2021-08-05 - Earliest claimed: 2016-01-21 - Assignees: VueReal Inc. - Applicants: VueReal Inc. - Inventors: Gholamreza Chaji - Web page: https://patentgrep.com/patent/US20210243894A1 ## CPC - H05K 1/111: {Pads for surface mounting, e.g. lay-out} - H05K 13/0015: {Orientation; Alignment; Positioning} - H05K 13/0069: {Holders for printed circuit boards} - H05K 13/04: Mounting of components {, e.g. of leadless components} - H10P 72/74: {using temporarily an auxiliary support} - G01R 31/2635: {Testing light-emitting diodes, laser diodes or photodiodes} - H10P 72/7414: {the auxiliary support including means facilitating the selective separation of some of a plurality of devices from the auxiliary support} - H10P 72/7434: {used in a transfer process involving at least two transfer steps, i.e. including an intermediate handle substrate} - H10P 72/744: {Details of chemical or physical process used for separating the auxiliary support from a device or a wafer} - H10P 74/207: {Electrical properties, e.g. testing or measuring of resistance, deep levels or capacitance-voltage characteristics} - H10P 74/23: {characterised by multiple measurements, corrections, marking or sorting processes} - H10W 72/01304: {using temporary auxiliary members, e.g. using sacrificial coatings or handle substrates} - H10W 72/01323: {in liquid form, e.g. by dispensing droplets or by screen printing} - H10W 72/01325: {in solid form} - H10W 72/0198: {batch processes} - H10W 72/0711: {Apparatus therefor} - H10W 72/07141: {Means for applying energy, e.g. ovens or lasers} - H10W 72/073: {of die-attach connectors} - H10W 72/07307: {the auxiliary member being a temporary substrate, e.g. a removable substrate} - H10W 72/07321: {Aligning} - H10W 72/07323: {Active alignment, e.g. using optical alignment using marks or sensors} - H10W 72/07327: {involving guiding structures, e.g. spacers or supporting members} - H10W 72/07331: {Connecting techniques} - H10W 72/07338: {hardening the adhesive by curing, e.g. thermosetting} - H10W 72/321: {Structures or relative sizes of die-attach connectors} - H10W 72/324: {Die-attach connectors having multiple side-by-side cores} - H10W 72/331: {Shapes of die-attach connectors} - H10W 72/334: {Cross-sectional shape, i.e. in side view} - H10W 72/344: {relative to underlying supporting features, e.g. bond pads, RDLs or vias} - H10W 72/354: {comprising polymers} - H10W 90/00: Package configurations - H10W 90/734: {between a chip and a stacked insulating package substrate, interposer or RDL} - H05K: PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 ## Abstract What is disclosed is a method of selectively transferring micro devices from a donor substrate to contact pads on a receiver substrate. Micro devices being attached to a donor substrate with a donor force. The donor substrate and receiver substrate are aligned and brought together so that selected micro devices meet corresponding contact pads. A receiver force is generated to hold selected micro devices to the contact pads on the receiver substrate. The donor force is weakened and the substrates are moved apart leaving selected micro devices on the receiver substrate. Several methods of generating the receiver force are disclosed, including adhesive, mechanical and electrostatic techniques. ## Claims ### Claim 1 A method of transferring a micro device, the method comprising: positioning a donor substrate comprising the micro device proximal to a receiver substrate, wherein the receiver substrate comprises a force modulator element creating transfer force for transferring the selected micro devices; and reducing the effect of said force generated by the force modulator element on unwanted micro devices. ### Claim 2 (depends on 1) The method of claim 1, wherein selectively reducing the effect of a force generated by the force modulator element comprises generating a reverse polarity of force surrounding the force modulating element. ### Claim 3 A method of transferring micro devices, the method comprising: positioning a donor substrate comprising micro devices proximal to a receiver substrate, wherein the receiver substrate comprises a current curable bonding layer; and transferring the micro devices by applying current to the bonding layer of selected micro devices. ### Claim 4 (depends on 3) The method of claim 3, wherein the current is applied using a circuit in the receiver substrate. ### Claim 5 (depends on 3) The method of claim 3, wherein the circuit in the receiver substrate is shared with a circuit associated the driving or controlling the selected micro devices. ### Claim 6 (depends on 3) The method of claim 3, wherein the bonding layer comprises one or more contact pads and selectively curing a portion of the bonding layer comprises curing a portion of the bonding layer between one or more contact pads. ### Claim 7 A receiver substrate used to receive a micro device from a donor substrate, the receiver substrate comprising: an array of one or more pad structures, wherein each pad structure comprises a conductive layer and a dielectric layer. ### Claim 8 (depends on 7) The receiver substrate of claim 7, wherein the dielectric layer can be modulated to be a conductive layer. ### Claim 9 (depends on 8) The receiver substrate of claim 8, wherein the dielectric layer is modulated to the conductive layer during operation to couple a circuit in the receiver substrate to the micro device. ### Claim 10 (depends on 8) The receiver substrate of claim 8, wherein the dielectric layer is modulated to the conductive layer using a doped layer. ### Claim 11 (depends on 8) The receiver substrate of claim 8, wherein the dielectric layer is modulated to the conductive layer using a laser to induce dielectric breakdown. ### Claim 12 A method of transferring a micro device, the method comprising: positioning a donor substrate comprising a micro device proximal to a receiver substrate, wherein the receiver substrate comprises a pad structure having a dielectric layer and a conductive layer; transferring the micro device from the donor substrate to the pad structure; and coupling the first micro device and the conductive layer by removing the dielectric layer, wherein the dielectric layer is removed by the means of thermal force. ### Claim 13 (depends on 12) The method of claim 12, further comprising providing a deformable layer on top of one of: a receiver the contact pad or the micro devices to adjust for different heights in the micro devices. ### Claim 14 (depends on 13) The method of claim 13, wherein the deformable layer consists of either-one of: another conductive layer, high resistive layer, another dielectric layer on top of the dielectric layer or a part of the dielectric layer. ### Claim 15 (depends on 12) The method of claim 12, wherein the dielectric layer is removed partially or fully.