# US 2025/0098367 A1 · Red light-emitting diode > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0098367 A1 - Document ID: US20250098367A1 - Status: Published application - Kind: A1 - Application number: 18/404,884 - Filed: 2024-01-04 - Published: 2025-03-20 - Earliest claimed: 2023-09-20 - Assignees: Sundiode Korea - Applicants: Sundiode Korea - Inventors: James Chinmo KIM; Sungsoo YI - Web page: https://patentgrep.com/patent/US20250098367A1 ## CPC - 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 20/825: containing nitrogen, e.g. GaN - H10H: INORGANIC LIGHT-EMITTING SEMICONDUCTOR DEVICES HAVING POTENTIAL BARRIERS ## Abstract A red light-emitting diode utilizing electron tunneling is disclosed. Tunneling occurs between two well layers arranged around a barrier layer due to the wave-like properties of electrons. Due to the unique properties and strain of the crystal structure, the polarization in the well layer causes displacement of electrons and holes. The electrons tunnel through the barrier layer and recombine with holes in the valence band on the opposite side. ## Claims ### Claim 1 A red light-emitting diode comprising: a first well layer; a barrier layer formed on the first well layer and having a higher bandgap than the first well layer; and a second well layer formed on the barrier layer and having a lower bandgap than the barrier layer, wherein the first well layer and the second well layer have a tilted band structure, and wherein electrons in the first well layer recombine with holes in the second well layer through tunneling to perform a light emission operation. ### Claim 2 (depends on 1) The red light-emitting diode of claim 1, wherein the barrier layer is made of InGaN, GaN, or AlGaN. ### Claim 3 (depends on 2) The red light-emitting diode of claim 2, wherein the first well layer or the second well layer is made of InGaN and has a fraction of indium (In) that is higher than that of the barrier layer. ### Claim 4 (depends on 1) The red light-emitting diode of claim 1, wherein the light emission operation occurs at the interface region between the second well layer and the barrier layer. ### Claim 5 (depends on 4) The red light-emitting diode of claim 4, wherein the electrons in the first well layer have a probability of recombining with the holes in the second well layer according to Equation 1 below: T e , SIR ≈ exp [ - 2 ⁢ 2 ⁢ m e ⁢ L 2 ℏ 2 ⁢ E bh ] [ Equation ⁢ 1 ] where Te,SIR represents the probability that the electrons in the conduction band of the first well layer will recombine with the holes in the second well layer or the probability that the electrons from the first well layer distributed at the interface with the barrier layer will also be distributed at the interface between the second well layer and the barrier layer, me represents the effective mass of electron, L is the thickness of the barrier layer, Ebh is the energy difference of the barrier layer as seen by the electrons in the first well layer, ℏ is h/(2π), and h is the Planck's constant. ### Claim 6 (depends on 4) The red light-emitting diode of claim 4, wherein the barrier layer is made of InGaN, GaN, or AlGaN and has a thickness of 1 or 2 lattice constants in the c-axis direction. ### Claim 7 (depends on 6) The red light-emitting diode of claim 6, wherein the barrier layer has a thickness of 0.5 nm to 1 nm. ### Claim 8 (depends on 7) The red light-emitting diode of claim 7, wherein a first contribution rate to light emission due to the recombination of the electrons in the first well layer and the holes in the second well layer is higher than a second contribution rate to light emission due to the recombination of electrons and holes within the well layer itself. ### Claim 9 (depends on 8) The red light-emitting diode of claim 8, wherein the second contribution rate is less than 22% compared to the total contribution. ### Claim 10 (depends on 1) The red light-emitting diode of claim 1, wherein the energy of the conduction band of the first well layer decreases toward the barrier layer, and the energy of the conduction band of the second well layer increases toward the barrier layer. ### Claim 11 A red light-emitting diode comprising: a first well layer made of InGaN; a barrier layer formed on the first well layer, through which electrons of a conduction band in the first well layer can tunnel; and a second well layer made of InGaN and formed on the barrier layer, where the tunneling electrons in the first well layer recombine with holes, wherein the concentration of indium in the first well layer increases toward the barrier layer, and the concentration of indium in the second well layer also increase toward the barrier layer. ### Claim 12 (depends on 11) The red light-emitting diode of claim 11, wherein the first well layer has a fraction of indium (In) that emits red light at the interface region with the barrier layer. ### Claim 13 (depends on 11) The red light-emitting diode of claim 11, wherein the first well layer has a fraction of indium (In) that causes a blue shift from red light with increasing distance away from the barrier layer. ### Claim 14 (depends on 11) The red light-emitting diode of claim 11, wherein the barrier layer comprises GaN or InGaN having a fraction of indium (In) that is lower than that of the first well layer. ### Claim 15 (depends on 11) The red light-emitting diode of claim 11, wherein the light emission operation occurs at the interface region between the second well layer and the barrier layer. ### Claim 16 (depends on 15) The red light-emitting diode of claim 15, wherein the electrons in the first well layer have a probability of recombining with the holes in the second well layer according to Equation 1 below: T e , SIR ≈ exp [ - 2 ⁢ 2 ⁢ m e ⁢ L 2 ℏ 2 ⁢ E bh ] [ Equation ⁢ 1 ] where Te,SIR represents the probability that the electrons in the conduction band of the first well layer will recombine with the holes in the second well layer or the probability that the electrons from the first well layer distributed at the interface with the barrier layer will also be distributed at the interface between the second well layer and the barrier layer, me represents the effective mass of electron, L is the thickness of the barrier layer, Ebh is the energy difference of the barrier layer as seen by the electrons in the first well layer, ℏ is h/(2π), and h is the Planck's constant. ### Claim 17 (depends on 15) The red light-emitting diode of claim 15, wherein the barrier layer is made of GaN, InGaN, or AlGaN and has a thickness of 1 or 2 lattice constants in the c-axis direction. ### Claim 18 (depends on 17) The red light-emitting diode of claim 17, wherein the barrier layer has a thickness of 0.5 nm to 1 nm.