Glo Ab

Samsung Electronics Co., Ltd.

Nanosys, Inc.

Glo Technologies LLC

Anusha Pokhriyal

Sharon N Farrens

Fariba Danesh

Timothy Gallagher

Nathan Fredrick Gardner

Daniel Bryce Thompson

Saket Chadda

Miljenko Modric

Fredrick A Kish, Jr

Zulal Tezcan Ozel

Tsun Yin Lau

Mariana Munteanu

Jr Fredrick A Kish

A method includes transferring a first subset of the first LEDs from a first substrate to a first backplane to form first subpixels in pixel regions, transferring a first subset of the second LEDs to a second backplane and separating the first subset of the second LEDs from a second substrate to leave first vacancies on the second substrate, forming an additional electrically conductive material on a second subset of second LEDs located on the second substrate after transferring the first subset of the second LEDs to the second backplane, positioning the second substrate over the first backplane, such that the first subpixels are disposed in the first vacancies, and transferring the second subset of the second LEDs to a second subset of bonding structures on the first backplane to form second subpixels in the pixel regions, while a gap exists between the first subpixels and the second substrate.

Subpixel light emitting diodes for direct view display and methods of making the same

A transfer method includes providing a first light emitting diode on a first substrate, performing a partial laser liftoff of the first light emitting diode from the first substrate, laser bonding the first light emitting diode to the backplane after performing the partial laser liftoff, and separating the first substrate from the first light emitting diode after the laser bonding.

Partial laser liftoff process during die transfer and structures formed by the same

Selective transfer of dies including semiconductor devices to a target substrate can be performed employing local laser irradiation. Coining of at least one set of solder material portions can be employed to provide a planar surface-to-surface contact and to facilitate bonding of adjoining pairs of bond structures. Laser irradiation on the solder material portions can be employed to sequentially bond selected pairs of mated bonding structures, while preventing bonding of devices not to be transferred to the target substrate. Additional laser irradiation can be employed to selectively detach bonded devices, while not detaching devices that are not bonded to the target substrate. The transferred devices can be pressed against the target substrate during a second reflow process so that the top surfaces of the transferred devices can be coplanar. Wetting layers of different sizes can be employed to provide a trapezoidal vertical cross-sectional profile for reflowed solder material portions.

Method of selectively transferring LED die to a backplane using height controlled bonding structures

A backplane can have a non-planar top surface. Insulating material portions including planar top surface regions located within a same horizontal plane are formed over the backplane. A two-dimensional array of metal plate clusters is formed over the insulating material portions. Each of the metal plate clusters includes a plurality of metal plates. Each metal plate includes a horizontal metal plate portion overlying a planar top surface region and a connection metal portion connected to a respective metal interconnect structure in the backplane. A two-dimensional array of light emitting device clusters is bonded to the backplane through respective bonding structures. Each light emitting device cluster includes a plurality of light emitting devices overlying a respective metal plate cluster.

LED backplane having planar bonding surfaces and method of making thereof

Light emitting devices can be disposed on the front side of a transparent backplane. A laser beam can be irradiated through the transparent backplane and onto a component located on the front side of the transparent backplane. In one embodiment, the component may be a solder material portion that is reflowed to bond the light emitting devices to the transparent backplane. In another embodiment, the component may be a solder material bonded to a defective bonded light emitting device. In this case, the laser irradiation can reflow the solder material to dissociate the defective bonded light emitting device from the transparent backplane. In yet another embodiment, the component may be a device component that is electrically modified by the laser irradiation.

Through backplane laser irradiation for die transfer

Backplane-side bonding structures including a common metal are formed on a backplane. Multiple source coupons are provided such that each source coupon includes a transfer substrate and an array of devices to be transferred. Each array of devices are arranged such that each array includes a unit cell structure including multiple devices of the same type and different types of bonding structures including different metals that provide different eutectic temperatures with the common metal. Different types of devices can be sequentially transferred to the backplane by sequentially applying the supply coupons and selecting devices providing progressively higher eutectic temperatures between respective bonding pads and the backplane-side bonding structures. Previously transferred devices stay on the backplane during subsequent transfer processes, enabling formation of arrays of different devices on the backplane.

Method of forming an array of a multi-device unit cell

A backplane optionally having stepped horizontal surfaces and optionally embedding metal interconnect structures is provided. First conductive bonding structures are formed on first stepped horizontal surfaces. First light emitting devices on a first transfer substrate are disposed on the first conductive bonding structures, and a first subset of the first light emitting devices is bonded to the first conductive bonding structures. Laser irradiation can be employed to selectively disconnect the first subset of the first light emitting devices from the first transfer substrate while a second subset of the first light emitting devices remains attached to the first transfer substrate. Additional devices on each additional transfer substrate can be bonded to additional conductive bonding structures on the backplane employing the same method provided that the additional devices are not present in positions that would overlap with pre-existing first light emitting devices or devices on the backplane at a bonding position.

Method of making a light emitting diode array on a backplane

A light emitting device and method of forming the same, the light emitting device including: a substrate, a buffer layer disposed on the substrate, a semiconductor mesa disposed on the buffer layer and including a first semiconductor layer, a light emitting active layer disposed on the first semiconductor layer, and a second semiconductor layer disposed on the first semiconductor layer, a contact layer disposed on an upper surface of the mesa, a passivation layer covering sidewalls of the mesa and the contact layer, and a cap structure including a reflective layer covering an upper surface of the contact layer, and a solder layer including a recess in which the reflective layer is disposed.

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Sunnyvale, CA, United States of America

Anusha Pokhriyal