Facebook Technologies, LLC

Meta Platforms Technologies, LLC

Daniel Bryce Thompson

James Small

Stephan Lutgen

Pooya Saketi

Daniel Brodoceanu

William Padraic Henry

David Massoubre

Markus Broell

Thomas Lauermann

Michael Grundmann

François Gérard Franck Olivier

Vasily Zabelin

Disclosed herein are techniques for reducing the pitch between light-emitting diodes (LEDs) in an array of LEDs. According to an aspect of the invention, a method includes forming a plurality of stacks of layers on a surface of a semiconductor, with a p contact at an interface between each stack and a p-type layer of the semiconductor. The semiconductor is etched to form a plurality of mesa shapes corresponding to the plurality of stacks. A dielectric is formed on at least a portion of each mesa shape and at least a portion of each stack. A reflector is formed on at least a portion of the dielectric and at least a portion of the semiconductor to provide an n contact at an interface between the reflector and an n-type layer of the semiconductor. The reflector is physically separated from the p contact for each stack.

LEDs arrays having a reduced pitch

Disclosed herein is an apparatus including a first three-dimensional (3-D) structure, a second 3-D structure, and a conductive layer. The first 3D structure includes a first-type doped semiconductor material having a semi-polar facet. The second 3-D structure forms a light-emitting diode (LED) and includes a second-type doped semiconductor material, an active layer, and the first-type doped semiconductor material. The conductive layer at least partially overlays and is in ohmic contact with the semi-polar facet. The conductive layer is configured to carry current that flows between the semi-polar facet and the active layer. In some embodiments, the first-type doped semiconductor material may include an N-type doped semiconductor material, and the second-type doped semiconductor material may include a P-type doped semiconductor material. The first-type doped semiconductor material of both 3-D structures may be etched from a common first-type doped semiconductor epitaxial layer.

3-D structure for increasing contact surface area for LEDs

Described are light emitting apparatus with self-aligned elements and techniques for manufacturing such light emitting apparatus. In certain embodiments, a method for manufacturing a light emitting apparatus involves forming a plurality of semiconductor layers including a first semiconductor layer, a second semiconductor layer, and a light emission layer between the first semiconductor layer and the second semiconductor layer. The method further involves forming an electrical contact and a spacer. The electrical contact is formed on a surface of the first semiconductor layer. The spacer is formed on the surface of the first semiconductor layer, around the electrical contact. After forming the spacer, the plurality of semiconductor layers is etched to form a mesa with sidewalls that extend from an outer edge of the spacer. The spacer operates as an etch mask that causes the electrical contact to be substantially centered between opposing sidewalls of the mesa.

Method for manufacturing a spacer for self-aligned mesa

Techniques disclosed herein relate to micro light emitting diodes (micro-LEDs) for a display system. A display system includes an array of micro light emitting diodes (micro-LEDs), an array of output couplers optically coupled to the array of micro-LEDs and configured to extract light emitted by respective micro-LEDs in the array of micro-LEDs, a waveguide display, and display optics configured to couple the light emitted by the array of micro-LEDs and extracted by the array of output couplers into the waveguide display. Each output coupler in the array of output couplers is configured to direct a chief ray of the light emitted by a respective micro-LED in the array of micro-LEDs to a different respective direction.

Micro-LED design for chief ray walk-off compensation

Disclosed herein are techniques for reducing the pitch between light-emitting diodes (LEDs) in an array of LEDs. According to an aspect of the invention, a device includes an array having a plurality of LEDs and a reflector that is in Ohmic contact with at least two adjacent LEDs of the plurality of LEDs. Each LED of the plurality of LEDs includes a p contact, and the reflector is physically separated from the p contact of each LED of the plurality of LEDs.

LED arrays having a reduced pitch

Disclosed herein is an apparatus including a first three-dimensional (3-D) structure and a second 3-D structure. The first 3-D structure may include a first-type doped semiconductor material having semi-polar facets. The second 3-D structure may form a light-emitting diode (LED). The second 3-D structure may include a second-type doped semiconductor material, an active layer, and the first-type doped semiconductor material. The apparatus may also include a conductive layer which at least partially overlays and is in ohmic contact with the semi-polar facets of the first-type doped semiconductor material. The first-type doped semiconductor material of the first 3-D structure and the first-type doped semiconductor material of the second 3-D structure may be etched from a common first-type doped semiconductor epitaxial layer. In some embodiments, the first-type doped semiconductor material may include an N-type doped semiconductor material, and the second-type doped semiconductor material may include a P-type doped semiconductor material.

Techniques are disclosed for utilizing an etchant-accessible carrier substrate that enables etching through the carrier substrate. More particularly, an etchant is provided access to the adhesive layer via the etchant-accessible carrier substrate via one or more holes in the etchant-accessible carrier substrate. The size and/or pattern of the holes may vary, depending on desired functionality. The etching process may be optionally stopped prior to the removal of all of the adhesive layer such that at least a portion of the adhesive layer remains, which can help ensure the light-emitting structures do not slip off of the etchant-accessible carrier substrate as the etchant-accessible carrier substrate is moved from one location to another during the fabrication process.

Etchant-accessible carrier substrate for display manufacture

Described are light emitting apparatus with self-aligned elements and techniques for manufacturing such light emitting apparatus. In certain embodiments, a light emitting apparatus includes a mesa formed by a plurality of semiconductor layers. The light emitting apparatus further includes an electrical contact on one of the semiconductor layers and a spacer around the electrical contact. The spacer is aligned with respect to the electrical contact, which permits etching around the spacer to define the shape of the mesa in such a way that the mesa is also aligned with respect to the electrical contact. In particular, the electrical contact is substantially centered between opposing sidewalls of the mesa.

Spacer for self-aligned mesa

Disclosed are techniques related to reflectors having overall mesa shapes. Such a reflector may be formed over an overall mesa-shaped, layered structure of an apparatus for emitting light. The overall mesa-shaped, layered structure may comprise a mesa complement structure, a first-type doped semiconductor, a light emission layer, and a second-type doped semiconductor arranged in layers. Thus, the reflector may be configured to collimate light that emits from the light emission layer and reaches the reflector through the mesa complement structure.

Reflectors having overall mesa shapes

Described herein are light emitting apparatuses with minimized light emission areas and methods for fabricating such apparatuses. In certain embodiments, the emission area corresponds to an area of an electrical contact and is minimized by minimizing the area of the electrical contact. The electrical contact is configured to receive an electrical signal that causes a light emission layer to generate light. The light emission layer is between a first semiconductor layer and a second semiconductor layer, with the electrical contact being formed on the second semiconductor layer. To protect the second semiconductor layer from damage during an etching process, a conductive body is formed around the electrical contact, where the conductive body is a non-ohmic contact to the second semiconductor layer. The conductive body acts as an etch stop against unintended etching of the second semiconductor layer as a result of an alignment error during the etching process.

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Cork, Ireland

Daniel Bryce Thompson