# US 11,444,065 B2 · Light emitting diode device containing a positive photoresist insulating spacer and a conductive sidewall contact and method of making the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,065 B2 - Document ID: US11444065B2 - Status: Granted - Kind: B2 - Application number: 16/884,523 - Filed: 2020-05-27 - Published: 2020-12-03 - Granted: 2022-09-13 - Earliest claimed: 2019-05-30 - Assignees: Nanosys, Inc. - Applicants: Glo AB - Inventors: Willibrordus Gerardus Maria Van Den Hoek; Tsun Yin Lau; Cameron Danesh; Fariba Danesh - Web page: https://patentgrep.com/patent/US11444065B2 ## CPC - H10W 90/00: Package configurations - H10H 20/811: having quantum effect structures or superlattices, e.g. tunnel junctions - H10H 20/812: within the light-emitting regions, e.g. having quantum confinement structures - H10H 20/813: having a plurality of light-emitting regions, e.g. multi-junction LEDs or light-emitting devices having photoluminescent regions within the bodies - H10H 20/815: having stress relaxation structures, e.g. buffer layers - H10H 20/821: of the light-emitting regions, e.g. non-planar junctions - H10H 20/824: comprising only Group III-V materials, e.g. GaP - H10H 20/825: containing nitrogen, e.g. GaN - H10H 20/833: Transparent materials - H10H 20/835: {Reflective materials} - H10H 20/854: characterised by their material, e.g. epoxy or silicone resins - H10H 20/857: Interconnections, e.g. lead-frames, bond wires or solder balls - H10H 20/032: {of electrodes} - H10H 20/0362: {of encapsulations} - H10H 20/0364: {of interconnections} - H10H 29/10: Integrated devices comprising at least one light-emitting semiconductor component covered by group H10H20/00 (active-matrix LED displays H10H29/30) - H10W: GENERIC PACKAGES, INTERCONNECTIONS, CONNECTORS OR OTHER CONSTRUCTIONAL DETAILS OF DEVICES COVERED BY CLASS H10 - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract A light emitting device includes a backplane, an array of light emitting diodes attached to a frontside of the backplane, a positive tone, imageable dielectric material layer, such as a positive photoresist layer, located on the frontside of the backplane and laterally surrounding the array of light emitting diodes, such that sidewalls of the light emitting diodes contacting the positive tone, imageable dielectric material layer have a respective reentrant vertical cross-sectional profile, and at least one common conductive layer located over the positive tone, imageable dielectric material layer and contacting the light emitting diodes. ## Claims ### Claim 1 A light emitting device comprising: a backplane; an array of light emitting diodes attached to a frontside of the backplane; a positive tone, imageable dielectric material layer located on the frontside of the backplane and laterally surrounding the array of light emitting diodes, wherein sidewalls of the light emitting diodes contacting the positive tone, imageable dielectric material layer have a respective reentrant vertical cross-sectional profile such that a lateral extent of the light emitting diodes decreases with increasing vertical distance from a top surface of the light emitting diodes towards the frontside of the backplane; and at least one common conductive layer located over the positive tone, imageable dielectric material layer and contacting the light emitting diodes. ### Claim 2 (depends on 1) The light emitting device of claim 1, wherein the at least one common conductive layer comprises: a conductive adhesion layer contacting upper portions of sidewalls of the light emitting diodes and a top surface of the positive tone, imageable dielectric material layer; and a transparent conductive layer contacting a frontside surface of the conductive adhesion layer. ### Claim 3 (depends on 1) The light emitting device of claim 1, wherein: the positive tone, imageable dielectric material layer comprises a positive photoresist layer; and the positive photoresist layer comprises tapered encirclement portions that laterally encircle and contact a respective one of the light emitting diodes and include a respective set of inner sidewalls and a respective set of outer sidewalls, wherein a lateral spacing between each of the inner sidewalls and a most proximal one of the outer sidewalls decreases to zero with an increase in a vertical distance from the backplane. ### Claim 4 (depends on 3) The light emitting device of claim 3, wherein: the inner sidewalls of the tapered encirclement portions have a taper angle in a range from 1 degree to 15 degrees with respective to a direction perpendicular to a frontside surface of the backplane; and the outer sidewalls of the tapered encirclement portions include concave sidewalls having a variable taper angle that increases with a lateral distance from a geometrical center of a most proximal one of the light emitting diodes. ### Claim 5 (depends on 3) The light emitting device of claim 3, wherein: each of the light emitting diodes comprise a respective active region configured to emit light upon application of a bias voltage thereacross; a matrix portion of the positive photoresist layer adjoining the tapered encirclement portions and continuously extending around each of the light emitting diodes; and the top surface of the positive photoresist layer is located between a first horizontal plane including top surfaces of the light emitting diodes and a second horizontal plane including the active regions of the light emitting diodes. ### Claim 6 (depends on 2) The light emitting device of claim 2, wherein a subset of the light emitting diodes comprise a respective n-doped compound semiconductor substrate layer having a horizontal cross-sectional area that strictly increases with a distance from the frontside of the backplane. ### Claim 7 (depends on 6) The light emitting device of claim 6, wherein the conductive adhesion layer contacts sidewalls of the n-doped compound semiconductor substrate layer. ### Claim 8 (depends on 2) The light emitting device of claim 2, wherein the conductive adhesion layer contacts top surfaces of the light emitting diodes. ### Claim 9 (depends on 8) The light emitting device of claim 8, wherein the conductive adhesion layer comprises a transparent metallic material having a thickness in a range from 0.2 nm to 2 nm. ### Claim 10 (depends on 9) The light emitting device of claim 9, wherein the conductive adhesion layer comprises a material selected from Ti, TiW, or a layer stack of a Ti layer and an Al layer. ### Claim 11 (depends on 2) The light emitting device of claim 2, wherein: the conductive adhesion layer comprises an array of openings, wherein each light emitting diode among the array of light emitting diodes extends through a respective opening within the array of openings; and the conductive adhesion layer does not contact any top surface of the light emitting diodes. ### Claim 12 (depends on 11) The light emitting device of claim 11, wherein the conductive adhesion layer comprises a spin-on conductive material and has a planar top surface that is located below a horizontal plane including top surfaces of the light emitting diodes. ### Claim 13 (depends on 12) The light emitting device of claim 12, wherein the conductive adhesion layer comprises silver particles, silver nanowires, carbon nanotubes, or graphene sheets that are embedded within an organic matrix. ### Claim 14 (depends on 1) The light emitting device of claim 1, wherein each region of the light emitting device that overlies a top surface of a light emitting diode excludes light absorbing material. ### Claim 15 A light emitting device comprising: a backplane; an array of light emitting diodes attached to a frontside of the backplane; a positive tone, imageable dielectric material layer located on the frontside of the backplane and laterally surrounding the array of light emitting diodes, wherein sidewalls of the light emitting diodes contacting the positive tone, imageable dielectric material layer have a respective reentrant vertical cross-sectional profile; and at least one common conductive layer located over the positive tone, imageable dielectric material layer and contacting the light emitting diodes, wherein: the positive tone, imageable dielectric material layer comprises a positive photoresist layer; and the positive photoresist layer comprises tapered encirclement portions that laterally encircle and contact a respective one of the light emitting diodes and include a respective set of inner sidewalls and a respective set of outer sidewalls, wherein a lateral spacing between each of the inner sidewalls and a most proximal one of the outer sidewalls decreases to zero with an increase in a vertical distance from the backplane. ### Claim 16 A light emitting device comprising: a backplane; an array of light emitting diodes attached to a frontside of the backplane; a positive tone, imageable dielectric material layer located on the frontside of the backplane and laterally surrounding the array of light emitting diodes, wherein sidewalls of the light emitting diodes contacting the positive tone, imageable dielectric material layer have a respective reentrant vertical cross-sectional profile; and at least one common conductive layer located over the positive tone, imageable dielectric material layer and contacting the light emitting diodes, wherein: the at least one common conductive layer comprises a conductive adhesion layer contacting upper portions of sidewalls of the light emitting diodes and a top surface of the positive tone, imageable dielectric material layer, and a transparent conductive layer contacting a frontside surface of the conductive adhesion layer; and a subset of the light emitting diodes comprise a respective n-doped compound semiconductor substrate layer having a horizontal cross-sectional area that strictly increases with a distance from the frontside of the backplane. ### Claim 17 A light emitting device comprising: a backplane; an array of light emitting diodes attached to a frontside of the backplane; a positive tone, imageable dielectric material layer located on the frontside of the backplane and laterally surrounding the array of light emitting diodes, wherein sidewalls of the light emitting diodes contacting the positive tone, imageable dielectric material layer have a respective reentrant vertical cross-sectional profile; and at least one common conductive layer located over the positive tone, imageable dielectric material layer and contacting the light emitting diodes, wherein: the at least one common conductive layer comprises a conductive adhesion layer contacting upper portions of sidewalls of the light emitting diodes and a top surface of the positive tone, imageable dielectric material layer, and a transparent conductive layer contacting a frontside surface of the conductive adhesion layer; the conductive adhesion layer comprises an array of openings, wherein each light emitting diode among the array of light emitting diodes extends through a respective opening within the array of openings; and the conductive adhesion layer does not contact any top surface of the light emitting diode.