Sharp Laboratories of America, Inc

Elux, Inc.

Ehux, Inc.

Sharp Kabushiki Kaisha Corporation

Oregon State University

Jong-Jan Lee

Sheng Teng Hsu

Jer-shen Maa

Douglas James Tweet

Yuhao Lu

Paul John Schuele

Kurt M Ulmer

Kenji Alexander Sasaki

David R Evans

Sean Vail

Long Wang

Hidayat Kisdarjono

Fengyan Zhang

Wei-Wei Zhuang

Motoaki Nishijima

Tingkai Li

Wei Pan

Steven Roy Droes

Allen Burmaster

Seizoh Kakimoto

Yoshi Ono

John Hartzell

Changqing Zhan

Jon Matthew Speigle

Jinke Tang

Wei-Yuan Ma

Robert A Barrowcliff

Alexey Y Koposov

Gregory M Stecker

Xiulei Ji

Jie Song

Steve Droes

Nobuyoshi Awaya

Wei Luo

Sakae Wada

Clement Bommier

A microLED mass transfer stamping system includes a stamp substrate with an array of trap sites, each configured with a columnar-shaped recess to temporarily secure a keel extended from a bottom surface of a microLED. In the case of surface mount microLEDs, the keel is electrically nonconductive. In the case of vertical microLEDs, the keel is an electrically conductive second electrode. The stamping system also includes a fluidic assembly carrier substrate with an array of wells having a pitch separating adjacent wells that matches the pitch separating the stamp substrate trap sites. A display substrate includes an array of microLED pads with the same pitch as the trap sites. The stamp substrate top surface is pressed against the display substrate, with each trap site interfacing a corresponding microLED site, and the microLEDs are transferred. Fluidic assembly stamp substrates are also presented for use with microLEDs having keels or axial leads.

Fluidic assembly MicroLED mass transfer method

Fluidic assembly carrier substrate for microLED mass transfer

A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume. If the number of harvested microLED devices in the suspension is known, a calculation can be made of the number of microLED devices per unit of suspension volume.

Emissive element harvest

A system and method are provided for repairing an emissive element display. If a defective emissive element is detected in a subpixel, a subpixel repair interface isolates the defective emissive element. The repair interface may be a parallel repair interface with n number of selectively fusible electrically conductive repair nodes, connected in parallel to a control line of the matrix. Alternatively, the repair interface may be a series repair interface with m number of repair nodes, selectively connectable to bypass adjacent (defective) series-connected emissive elements. If the subpixel emissive elements are connected in parallel, and a defective low impedance emissive element is detected, a parallel repair interface fuses open a connection between the defective emissive element and a matrix control line. If the subpixels include series-connected emissive elements, and a high impedance emissive element is detected, a series repair interface forms a connection bypassing the defective emissive element.

System and method for the repair of serially connected display elements

Disclosed herein is a micro light emitting diode (microLED) display structure with emission from the back side of a transparent substrate, which can be manufactured by fluidic assembly. The architecture allows microLED displays or display tiles to be fabricated simply, with processing and interconnection only on one side of the backplane. The structure may incorporate reflectors in the fluidic assembly structures to direct substantially all of the emitted light toward the viewer. Also disclosed are microLEDs and emission backplanes designed to support a back emission display.

Back emission display

Fluidic assembly enabled mass transfer for microLED displays

System for the characterization of emissive elements

A uniform pressure gang bonding device and fabrication method are presented using an expandable upper chamber with an elastic surface. Typically, the elastic surface is an elastomer material having a Young's modulus in a range of 40 to 1000 kilo-Pascal (kPA). After depositing a plurality of components overlying a substrate top surface, the substrate is positioned over the lower plate, with the top surface underlying and adjacent (in close proximity) to the elastic surface. The method creates a positive upper chamber medium pressure differential in the expandable upper chamber, causing the elastic surface to deform. For example, the positive upper chamber medium pressure differential may be in the range of 0.05 atmospheres (atm) and 10 atm. Typically, the elastic surface deforms between 0.5 millimeters (mm) and 20 mm, in response to the positive upper chamber medium pressure differential.

Uniform pressure gang bonding method

System and method for the characterization and dispersal of emissive elements

System and method for the selective harvest of emissive elements

A fluidic assembly emissive display panel is presented with a plurality of wells exposing LED interfaces. Each LED interface is made up of a planar first interconnect platform having an x-axis first depth and is configured to accept an axial LED first electrode mounting wing. A planar second interconnect platform has the first depth and is configured to accept an axial LED second electrode mounting wing. A groove is interposed between the first and second interconnect platforms and has an x-axis second depth, greater than the first depth, and is configured to accept an axial LED body locking tooth. The axial LEDs have an inorganic LED body with two symmetrical locking teeth. First and second electrode mounting wings are electrically connected to corresponding LED interface first and second interconnect platforms, and aligned in a plane orthogonal to stacked LED body semiconductor layers.

Fluidic assembly emissive display using axial light emitting diodes (LEDs)

System and method for uniform pressure gang bonding

System and method for light emitting diode (LED) display repair

A system and method are provided for repairing an emissive display. Following assembly, the emissive substrate is inspected to determine defective array sites, and defect items are removed using a pick-and-remove process. In one aspect, the emissive substrate includes an array of wells, with emissive elements located in the wells, but not electrically connected to the emissive substrate. If the emissive elements are light emitting diodes (LEDs), then the emissive substrate is exposed to ultraviolet illumination to photoexcite the array of LED, so that LED illumination can be measured to determine defective array sites. The defect items may be determined to be misaligned, mis-located, or non-functional emissive elements, or debris. Subsequent to determining these defect items, the robotic pick-and-remove process is used to remove them. The pick-and-remove process can also be repurposed to populate empty wells with replacement emissive elements.

Pick-and-remove system with deformable contact surface

A hybrid light emitting diode (LED) display and fabrication method are provided. The method forms a stack of thin-film layers overlying a top surface of a substrate. The stack includes an LED control matrix and a plurality of pixels. Each pixel is made up of a first subpixel enabled using an inorganic micro LED (uLED), a second subpixel enabled using an organic LED (OLED), and a third subpixel enabled using an OLED. The first subpixel emits a blue color light, the second subpixel emits a red color light, and the third subpixel emits a green color light. In one aspect, the stack includes a plurality of wells in a top surface of the stack, populated by the LEDs. The uLEDs may be configured vertical structures with top and bottom electrical contacts, or surface mount top surface contacts. The uLEDs may also include posts for fluidic assembly orientation.

Method for fabricating a hybrid display using inorganic micro light emitting diodes (uLEDs) and organic LEDs (OLEDs)

Growing community of inventors

Camas, WA, United States of America

Jong-Jan Lee