MICRO LED STRUCTURE AND MICRO DISPLAY PANEL
A micro light emitting diode (LED) structure, includes a mesa structure. The mesa structure further includes a first semiconductor layer having a first conductive type, a light emitting layer formed on the first semiconductor layer, and a second semiconductor layer formed on the light emitting layer, the second semiconductor layer having a second conductive type different from the first conductive type. The second semiconductor layer further includes a semiconductor region and an ion implantation region formed around the semiconductor region, the ion implantation region having a resistance higher than a resistance of the semiconductor region.
1 . A micro light emitting diode (LED) structure, comprising:
a mesa structure, comprising:
a first semiconductor layer having a first conductive type;
a light emitting layer formed on the first semiconductor layer; and
a second semiconductor layer formed on the light emitting layer, the second semiconductor layer having a second conductive type different from the first conductive type;
wherein the second semiconductor layer further comprises:
a semiconductor region; and
an ion implantation region formed around the semiconductor region.
2 . The micro LED structure according to claim 1 , further comprising:
a top contact formed on an upper surface of the second semiconductor layer, the top contact having the second conductive type; and
a bottom contact formed on a bottom surface of the first semiconductor layer, the bottom contact having the first conductive type.
3 . The micro LED structure according to claim 2 , wherein a center of the bottom contact, a center of the top contact, and a center of the semiconductor region are aligned along a same axis perpendicular to the upper surface of the second semiconductor layer, and
wherein a diameter of the ion implantation region is greater than or equal to a diameter of the top contact.
4 . The micro LED structure according to claim 1 , wherein the ion implantation region comprises at least one type of implanted ions.
5 . The micro LED structure according to claim 4 , wherein the implanted ions are selected from one or more of the following ions: hydrogen, nitrogen, fluorine, oxygen, carbon, argon, phosphorus, boron, silicon, sulfur, arsenic, chlorine, and metal ions.
6 . The micro LED structure according to claim 5 , wherein the metal ions are selected from one or more of zinc, copper, indium, aluminum, nickel, titanium, magnesium, chromium, gallium, tin, antimony, tellurium, tungsten, tantalum, germanium, molybdenum, and platinum.
7 . The micro LED structure according to claim 1 , wherein a thickness of the first semiconductor layer is greater than a thickness of the second semiconductor layer.
8 . The micro LED structure according to claim 7 , wherein the thickness of the first semiconductor layer ranges from 700 nm to 2 μm and the thickness of the second semiconductor layer ranges from 100 nm to 200 nm.
9 . The micro LED structure according to claim 2 , wherein:
a thickness of the second semiconductor region is greater than or equal to a thickness of the ion implantation region,
a diameter of the semiconductor region is greater than or equal to a diameter of the top contact, and
a diameter of the ion implantation region is equal to or greater than the diameter of the semiconductor region.
10 . The micro LED structure according to claim 9 , wherein the diameter of the semiconductor region is less than or equal to three times of the diameter of the top contact, and the diameter of the ion implantation region is greater than two times of the semiconductor region.
11 . The micro LED structure according to claim 9 , wherein:
the thickness of the second semiconductor region ranges from 100 nm to 200 nm,
the thickness of the ion implantation region ranges from 100 nm to 150 nm,
the diameter of the ion implantation region ranges from 100 nm to 1200 nm, and
the diameter of the top contact ranges from 20 nm to 50 nm.
12 . The micro LED structure according to claim 1 , wherein a thickness of the light emitting layer is less than a thickness of the first semiconductor layer.
13 . The micro LED structure according to claim 1 , wherein the light emitting layer is formed by a quantum well layer located between the first semiconductor layer and the second semiconductor layer.
14 . The micro LED structure according to claim 13 , wherein a thickness of the quantum well layer is less than or equal to 30 nm.
15 . The micro LED structure according to claim 13 , wherein the quantum well layer comprises three or less than three pairs of quantum wells.
16 . The micro LED structure according to claim 2 , further comprising a top conductive layer formed on the second semiconductor layer and the top contact.
17 . The micro LED structure according to claim 1 , further comprising a first reflective mirror formed on a bottom surface of the first semiconductor layer.
18 . The micro LED structure according to claim 17 , further comprising a second reflective mirror formed inside of the first semiconductor layer.
19 . The micro LED structure according to claim 1 , wherein the ion implantation region having a resistance higher than a resistance of the semiconductor region.
20 . A micro display panel, comprising:
a micro light emitting diode (LED) array comprising:
a first micro LED structure according to claim 1 ; and
an integrated circuit (IC) back plane formed under the first micro LED structure,
wherein the first micro LED structure is electrically coupled to the IC back plane.
21 . The micro display panel according to claim 20 , wherein the first micro LED structure further comprises:
a bottom contact formed on a bottom surface of the first semiconductor layer, and
a metal bonding structure formed on a bottom surface of the bottom contact.
22 . The micro display panel according to claim 21 , further comprising a top conductive layer formed on the second semiconductor layer and configured to cover the micro display panel,
wherein the metal bonding structure comprises a connected hole or a metal bonding layer, a first side of the metal bonding structure is connected to the bottom contact, and a second side of the metal bonding structure is connected to the IC back plane.
23 . The micro display panel according to claim 21 , further comprising:
a second micro LED structure according to claim 1 ; and
a dielectric layer,
wherein the second micro LED structure is located adjacent to the first micro LED structure, and
wherein the dielectric layer is not conductive and is formed between the mesa structures of the first and second micro LED structures.
24 . The micro display panel according to claim 23 , wherein material of the dielectric layer is selected from at least one of SiO 2 , Si 3 N 4 , Al 2 O 3 , AlN, HfO 2 , TiO 2 and ZrO 2 .
25 . The micro display panel according to claim 23 , further comprising a reflective structure formed in the dielectric layer and between the mesa structures of the first and second micro LED structures, wherein the reflective structure does not contact the mesa structures.
26 . The micro LED structure according to claim 25 , wherein the reflective structure has:
a top surface aligned with top surfaces of the mesa structures, and
a bottom surface aligned with bottom surfaces of the mesa structures.