# US 8,787,416 B2 · Laser diode using zinc oxide nanorods and manufacturing method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,787,416 B2 - Document ID: US8787416B2 - Status: Granted - Kind: B2 - Application number: 13/518,440 - Filed: 2010-09-10 - Published: 2012-12-13 - Granted: 2014-07-22 - Earliest claimed: 2009-12-23 - Assignees: Dongguk University Industry-Academic Cooperation Foundation - Applicants: Sang Wuk Lee; Tae Won Kang; Gennady Panin; Hak Dong Cho - Inventors: Sang Wuk Lee; Tae Won Kang; Gennady Panin; Hak Dong Cho - Web page: https://patentgrep.com/patent/US8787416B2 ## CPC - H01S 5/327: in AIIBVI compounds, e.g. ZnCdSe-laser - B82Y 20/00: Nanooptics, e.g. quantum optics or photonic crystals - H01S 5/021: {Silicon based substrates} - H01S 5/04253: {having specific optical properties, e.g. transparent electrodes} - H01S 5/341: {Structures having reduced dimensionality, e.g. quantum wires} - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract Provided are a laser diode using zinc oxide nanorods and a manufacturing method thereof. The laser diode using zinc oxide nanorods according to one embodiment of the present disclosure includes: a wafer; an electrode layer formed on the wafer; a nanorod layer including a plurality of n-doped zinc oxide nanorods grown on the electrode layer; and a p-doped single crystal semiconductor layer that is physically in contact with the ends of the zinc oxide nanorods. ## Claims ### Claim 1 A laser diode using zinc oxide nanorods, comprising: a wafer; an electrode layer formed on the wafer; a nanorod layer comprising a plurality of n-doped zinc oxide nanorods grown on the electrode layer; a p-doped single crystal semiconductor layer that is physically in contact with ends of the zinc oxide nanorods; and metal layers formed on a bottom surface of the wafer and on the top surface of the single crystal semiconductor layer, after fixing the single crystal semiconductor layer to the nanorod layer, wherein the p-doped single crystal semiconductor layer is substantially planar and the metal layer is subjected to heat treatment to form ohmic junction. ### Claim 2 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the zinc oxide nanorods are aligned vertically to the wafer. ### Claim 3 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the zinc oxide nanorods are grown at any angle other than a right angle to the wafer. ### Claim 4 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the zinc oxide nanorods are spaced apart from each other in the shape of hexagonal columns, form a cavity with a distance of 0.3 μm to 300 μm in a direction of long axis in the nanorods having the shape of hexagonal columns, and form a cavity with a diameter of 100 nm to 1000 mn between parallel surfaces of a column in a direction of short axis, thereby performing laser generation using Febry-Perot interference of light in the nanorods. ### Claim 5 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, which further comprises a material filled in vacancies among the zinc oxide nanorods, wherein the material has a higher refractive index than air and a lower refractive index than zinc oxide. ### Claim 6 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the zinc oxide nanorods have a dopant concentration of 1×1016 to 9×1020/cm3, and the single crystal semiconductor layer has a dopant concentration of 1×1017 to 9×1020/cm3. ### Claim 7 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the wafer is any one selected from a metal wafer, silicon wafer, glass wafer and graphite wafer. ### Claim 8 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the electrode layer is any one of a metal layer and graphene layer. ### Claim 9 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the zinc oxide nanorods have a height ranging from 0.3 μm to 300 μm and a diameter ranging from 10 nm up to 1,000 nm. ### Claim 10 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the single crystal semiconductor layer includes any one selected from p-doped single crystal silicon (Si), gallium arsenide (GaAs) and gallium nitride (GaN) wafers. ### Claim 11 (depends on 1) The laser diode using zinc oxide nanorods according to claim 1, wherein the single crystal semiconductor layer is formed by a p-doped single crystal semiconductor thin film grown on a heterogeneous wafer. ### Claim 12 A laser diode using zinc oxide nanorods, comprising: a graphite wafer; a nanorod layer comprising a plurality of n-doped zinc oxide nanorods grown on the graphite wafer; a p-doped single crystal semiconductor layer that is physically in contact with ends of the zinc oxide nanorods; and metal layers formed on a bottom surface of the wafer and on the top surface of the single crystal semiconductor layer, after fixing the single crystal semiconductor layer to the nanorod layer, wherein the p-doped single crystal semiconductor layer is substantially planar and the metal layer is subjected to heat treatment to form ohmic junction. ### Claim 13 A method for fabricating a laser diode using zinc oxide nanorods, comprising: forming an electrode layer on a wafer; growing a plurality of n-doped zinc oxide nanorods on the electrode layer to form a nanorod layer; allowing a p-doped single crystal semiconductor layer to be in contact with the nanorod layer; applying a predetermined level of pressure to a top surface of the single crystal semiconductor layer to fix the single crystal semiconductor layer to the nanorod layer; and forming metal layers on a bottom surface of the wafer and on the top surface of the single crystal semiconductor layer, after fixing the single crystal semiconductor layer to the nanorod layer; and subjecting the metal layer to heat treatment to form ohmic junction, wherein the p-doped single crystal semiconductor layer is substantially planar. ### Claim 14 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the nanorod layer is formed by growing the zinc oxide nanorods directly on the metal electrode layer. ### Claim 15 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the nanorod layer is formed by growing the zinc oxide nanorods through any one of vapor phase transport, metal-organic source chemical vapor deposition, sputtering, chemical electrolysis deposition and screen printing processes. ### Claim 16 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the nanorod layer is formed by a process further including filling vacancies among the zinc oxide nanorods with a material having a refractive index higher than the refractive index of air and lower than that of zinc oxide. ### Claim 17 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the single crystal semiconductor layer is any one selected from single crystal silicon wafers, single crystal gallium arsenide (GaAs) wafers and single crystal gallium nitride (GaN) wafers. ### Claim 18 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the single crystal semiconductor layer is p-doped and includes any one of single crystal silicon, gallium arsenide, gallium nitride, indium tin oxide (ITO) and polymer layer, grown on a heterogeneous wafer. ### Claim 19 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the single crystal semiconductor layer is fixed to the nanorod layer by applying a pressure of 0.05-8 N/cm2 to the top surface of the single crystal semiconductor layer. ### Claim 20 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, wherein the single crystal semiconductor layer is fixed to the nanorod layer by a process further including applying epoxy with which a lateral surface of the single crystal semiconductor layer, a lateral surface of the electrode layer and a lateral surface of the wafer are linked to each other, while applying pressure to the top surface of the single crystal semiconductor layer, wherein the electrode layer comprises a metal electrode layer. ### Claim 21 (depends on 13) The method for fabricating a laser diode using zinc oxide nanorods according to claim 13, which further comprises attaching a heat sink layer to at least one of the top surface of the single crystal semiconductor layer and the bottom surface of the wafer. ### Claim 22 A method for fabricating a laser diode using zinc oxide nanorods, comprising: growing a plurality of n-doped zinc oxide nanorods on a graphite wafer to form a nanorod layer; allowing a p-doped single crystal semiconductor layer to be in contact with the nanorod layer; applying a predetermined level of pressure to the top surface of the single crystal semiconductor layer to fix the single crystal semiconductor layer to the nanorod layer; and forming metal layers on a bottom surface of the wafer and on the top surface of the single crystal semiconductor layer, after fixing the single crystal semiconductor layer to the nanorod layer; and subjecting the metal layer to heat treatment to form ohmic junction, wherein the p-doped single crystal semiconductor layer is substantially planar.