WO2015106061A1 - Optoelectronic devices and applications thereof - Google Patents
Optoelectronic devices and applications thereof Download PDFInfo
- Publication number
- WO2015106061A1 WO2015106061A1 PCT/US2015/010758 US2015010758W WO2015106061A1 WO 2015106061 A1 WO2015106061 A1 WO 2015106061A1 US 2015010758 W US2015010758 W US 2015010758W WO 2015106061 A1 WO2015106061 A1 WO 2015106061A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- matrix
- polycrystalline
- electric field
- semiconducting regions
- migrating
- Prior art date
Links
- 230000005693 optoelectronics Effects 0.000 title description 3
- 239000011159 matrix material Substances 0.000 claims abstract description 203
- 230000005684 electric field Effects 0.000 claims abstract description 63
- 238000000034 method Methods 0.000 claims abstract description 49
- 239000000470 constituent Substances 0.000 claims abstract description 11
- 239000004065 semiconductor Substances 0.000 claims description 78
- 229910052751 metal Inorganic materials 0.000 claims description 22
- 230000000737 periodic effect Effects 0.000 claims description 15
- 229910052723 transition metal Inorganic materials 0.000 claims description 9
- 150000003624 transition metals Chemical class 0.000 claims description 8
- 238000004519 manufacturing process Methods 0.000 claims description 7
- 230000005670 electromagnetic radiation Effects 0.000 claims description 2
- 239000010949 copper Substances 0.000 description 33
- 239000012190 activator Substances 0.000 description 20
- 125000002091 cationic group Chemical group 0.000 description 11
- 230000005855 radiation Effects 0.000 description 11
- 239000011572 manganese Substances 0.000 description 10
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 9
- 229910052802 copper Inorganic materials 0.000 description 9
- 230000015572 biosynthetic process Effects 0.000 description 7
- 229910052801 chlorine Inorganic materials 0.000 description 7
- 239000000460 chlorine Substances 0.000 description 7
- 239000000463 material Substances 0.000 description 7
- 238000002207 thermal evaporation Methods 0.000 description 7
- 238000000151 deposition Methods 0.000 description 6
- 230000008021 deposition Effects 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 230000037361 pathway Effects 0.000 description 6
- 238000005240 physical vapour deposition Methods 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 5
- 239000000758 substrate Substances 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 4
- 239000000956 alloy Substances 0.000 description 4
- 125000000129 anionic group Chemical group 0.000 description 4
- 238000000231 atomic layer deposition Methods 0.000 description 4
- 238000005229 chemical vapour deposition Methods 0.000 description 4
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 4
- 229910052737 gold Inorganic materials 0.000 description 4
- 239000010931 gold Substances 0.000 description 4
- AMGQUBHHOARCQH-UHFFFAOYSA-N indium;oxotin Chemical compound [In].[Sn]=O AMGQUBHHOARCQH-UHFFFAOYSA-N 0.000 description 4
- 238000002347 injection Methods 0.000 description 4
- 239000007924 injection Substances 0.000 description 4
- 150000002739 metals Chemical class 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 4
- SKRWFPLZQAAQSU-UHFFFAOYSA-N stibanylidynetin;hydrate Chemical compound O.[Sn].[Sb] SKRWFPLZQAAQSU-UHFFFAOYSA-N 0.000 description 4
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 description 3
- 229910052782 aluminium Inorganic materials 0.000 description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 3
- 239000000969 carrier Substances 0.000 description 3
- -1 cationic metals Chemical class 0.000 description 3
- 239000002019 doping agent Substances 0.000 description 3
- 150000002500 ions Chemical class 0.000 description 3
- 229910052748 manganese Inorganic materials 0.000 description 3
- 230000005012 migration Effects 0.000 description 3
- 238000013508 migration Methods 0.000 description 3
- 239000010453 quartz Substances 0.000 description 3
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 3
- 229910052709 silver Inorganic materials 0.000 description 3
- 239000004332 silver Substances 0.000 description 3
- GYHNNYVSQQEPJS-UHFFFAOYSA-N Gallium Chemical compound [Ga] GYHNNYVSQQEPJS-UHFFFAOYSA-N 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 2
- OAICVXFJPJFONN-UHFFFAOYSA-N Phosphorus Chemical compound [P] OAICVXFJPJFONN-UHFFFAOYSA-N 0.000 description 2
- RCAQADNJXBGEKC-UHFFFAOYSA-N [O].[In].[Sb] Chemical compound [O].[In].[Sb] RCAQADNJXBGEKC-UHFFFAOYSA-N 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 238000004220 aggregation Methods 0.000 description 2
- 150000004770 chalcogenides Chemical class 0.000 description 2
- 239000002800 charge carrier Substances 0.000 description 2
- 239000013626 chemical specie Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000005401 electroluminescence Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910052733 gallium Inorganic materials 0.000 description 2
- 150000004820 halides Chemical class 0.000 description 2
- 238000005286 illumination Methods 0.000 description 2
- HRHKULZDDYWVBE-UHFFFAOYSA-N indium;oxozinc;tin Chemical compound [In].[Sn].[Zn]=O HRHKULZDDYWVBE-UHFFFAOYSA-N 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229910052759 nickel Inorganic materials 0.000 description 2
- 229910052697 platinum Inorganic materials 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000005215 recombination Methods 0.000 description 2
- 230000006798 recombination Effects 0.000 description 2
- 238000004544 sputter deposition Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000007736 thin film deposition technique Methods 0.000 description 2
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 1
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 1
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 229910052692 Dysprosium Inorganic materials 0.000 description 1
- 229910052693 Europium Inorganic materials 0.000 description 1
- 229910052688 Gadolinium Inorganic materials 0.000 description 1
- 229910052772 Samarium Inorganic materials 0.000 description 1
- 229910052771 Terbium Inorganic materials 0.000 description 1
- 229910052775 Thulium Inorganic materials 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 238000010549 co-Evaporation Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- KBQHZAAAGSGFKK-UHFFFAOYSA-N dysprosium atom Chemical compound [Dy] KBQHZAAAGSGFKK-UHFFFAOYSA-N 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010894 electron beam technology Methods 0.000 description 1
- OGPBJKLSAFTDLK-UHFFFAOYSA-N europium atom Chemical compound [Eu] OGPBJKLSAFTDLK-UHFFFAOYSA-N 0.000 description 1
- UIWYJDYFSGRHKR-UHFFFAOYSA-N gadolinium atom Chemical compound [Gd] UIWYJDYFSGRHKR-UHFFFAOYSA-N 0.000 description 1
- 229910052736 halogen Inorganic materials 0.000 description 1
- 150000002367 halogens Chemical class 0.000 description 1
- 230000020169 heat generation Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052738 indium Inorganic materials 0.000 description 1
- APFVFJFRJDLVQX-UHFFFAOYSA-N indium atom Chemical compound [In] APFVFJFRJDLVQX-UHFFFAOYSA-N 0.000 description 1
- SIXIBASSFIFHDK-UHFFFAOYSA-N indium(3+);trisulfide Chemical compound [S-2].[S-2].[S-2].[In+3].[In+3] SIXIBASSFIFHDK-UHFFFAOYSA-N 0.000 description 1
- 229910052740 iodine Inorganic materials 0.000 description 1
- 239000011630 iodine Substances 0.000 description 1
- 230000031700 light absorption Effects 0.000 description 1
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 description 1
- 229910021645 metal ion Inorganic materials 0.000 description 1
- 229910052761 rare earth metal Inorganic materials 0.000 description 1
- 150000002910 rare earth metals Chemical class 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- KZUNJOHGWZRPMI-UHFFFAOYSA-N samarium atom Chemical compound [Sm] KZUNJOHGWZRPMI-UHFFFAOYSA-N 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- GZCRRIHWUXGPOV-UHFFFAOYSA-N terbium atom Chemical compound [Tb] GZCRRIHWUXGPOV-UHFFFAOYSA-N 0.000 description 1
- 229910000314 transition metal oxide Inorganic materials 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers
- H01L31/072—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by potential barriers the potential barriers being only of the PN heterojunction type
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
- H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
- H01L31/0264—Inorganic materials
- H01L31/032—Inorganic materials including, apart from doping materials or other impurities, only compounds not provided for in groups H01L31/0272 - H01L31/0312
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/0248—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies
- H01L31/0256—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by their semiconductor bodies characterised by the material
- H01L31/0264—Inorganic materials
- H01L31/0328—Inorganic materials including, apart from doping materials or other impurities, semiconductor materials provided for in two or more of groups H01L31/0272 - H01L31/032
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Definitions
- the present invention relates to optoelectronic devices and, in particular, to
- LEDs light emitting diodes
- LEDs light emitting diodes
- LEDs are constructed from semiconductor materials and, when forward biased, emit radiation.
- the emitted radiation can fall within the ultraviolet, visible or infrared region of the electromagnetic spectrum.
- Light emitting diodes offer the advantages of enhanced lifetimes, reduced heat production, and rapid illumination times.
- Electroluminescent devices compatible with alternating current sources have also been developed. These devices generally employ powder phosphor for light generation under an applied alternating electric field. While cost effective to produce, AC powder electroluminescent devices suffer dimming effects stemming from phosphor degradation. Additionally, phosphors can demonstrate widely heterogeneous micro structure further contributing to reduced light output.
- a method described herein comprises providing an electroluminescent phase between a first electrode and second electrode, the electroluminescent phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix.
- the migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the electroluminescent phase.
- the migrating atomic species aggregate in one or more regions of the first polycrystalline matrix, such as in grain boundaries and/or at sites of crystalline defects.
- Aggregation of the migrating atomic species renders these regions of the first polycrystalline matrix p-type or n-type semiconductor, wherein these semiconducting regions are constituents of p-n junctions of the electroluminescent phase.
- a method of making a photovoltaic device comprises providing a photosensitive phase between a first electrode and second electrode, the photosensitive phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix.
- the migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the photosensitive phase. Further, the semiconducting regions can also function as light absorption regions of the photosensitive phase.
- Figure 1 illustrates light emission from p-n junctions of an electroluminescent device formed according to a method described herein.
- a method described herein comprises providing an electroluminescent phase between a first electrode and second electrode, the electroluminescent phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix.
- the migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the electroluminescent phase.
- the migrating atomic species aggregate in one or more regions of the first polycrystalline matrix. Aggregation of the migrating atomic species renders these regions of the first polycrystalline matrix p-type or n-type semiconductor, wherein these semiconducting regions are constituents of p-n junctions of the electroluminescent phase.
- the first polycrystalline matrix can be of the formula MiX], wherein Mi is selected from the group consisting of metallic elements including transition metals and Xi is selected from the group consisting of non-metallic elements of Groups IV A, VA and VIA of the Periodic Table.
- M ⁇ for example, can be selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table. Groups of the Periodic Table described herein are identified according to the CAS designation.
- Mi is the sole migrating atomic species under the applied electric field.
- atomic species in addition to Mi may migrate, such as other cationic metallic atomic species and/or anionic species in the first polycrystalline matrix.
- migrating atomic species are not of the species forming the lattice of the first polycrystalline matrix.
- the migrating atomic species can comprise cationic and/or anionic dopants such as cationic metals, halides or chalcogenides.
- the first polycrystalline matrix can have any thickness not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix can have thickness selected from Table I.
- the first polycrystalline matrix can comprise Cu x S.
- cationic Cu can be the migrating atomic species. Under the applied electric field, cationic Cu can migrate in the polycrystalline matrix forming regions of Cu x S having stoichiometry of p-type semiconductor. In such embodiments, p-type regions of semiconducting Cu x S have a stoichiometry wherein x ranges from 1.8-2.
- Semiconducting regions of the first polycrystalline matrix can form p-n junctions with a layer of second polycrystalline semiconductor matrix adjacent to the first polycrystalline matrix.
- the second polycrystalline semiconductor matrix can be formed of compound semiconductor of opposite polarity of the semiconducting regions to form the p-n junctions.
- the second polycrystalline semiconductor matrix is of the formula M 2 X 2 , wherein M 2 is selected from the group consisting of metallic elements including transition metals and X 2 is selected from the group consisting of non-metallic elements of Groups IVA, VA and VIA of the Periodic Table.
- M 2 for example, can be selected from metallic elements of Groups IB, IIB and III A of the Periodic Table.
- the second polycrystalline semiconductor matrix can comprise one or more dopants and/or luminescent centers for providing radiation recombination of carriers received from the semiconducting regions of the first polycrystalline matrix.
- Luminescent centers are sites or locations in the second semiconductor matrix where charge carriers are relaxed by one or more radiative pathways. Luminescent centers can include defects or trap states for localizing injected charge carriers for radiative recombination.
- Luminescent centers can also include one or more atomic species doped or otherwise incorporated into the lattice and/or interstitial sites of the semiconductor matrix as an activator.
- Suitable activators include ions of transition metals, rare earth metals or mixtures thereof.
- activator of the second semiconductor matrix comprises one or more metal ions selected from Groups IB, IIIB, VIIB, VIIIB and IIIA of the Periodic Table.
- Activator in some embodiments, comprises ions of copper, manganese, silver, gadolinium, dysprosium, europium, samarium, terbium or thulium or mixtures thereof.
- the second semiconductor matrix can further comprise co-activator chemical species.
- Co-activator chemical species work in conjunction with activator for the relaxation of carriers by one or more radiative pathways.
- Co-activator can comprise ionic species selected from Groups IIIA and VIIA of the Periodic Table.
- co-activator can comprise ions of aluminum, indium, chlorine or iodine or mixtures thereof.
- co-activator can be present in the second semiconductor matrix in the absence of activator. In such embodiments, the co-activator can assist in self-radiative relaxation processes of the second semiconductor matrix in response to carriers introduced by semiconducting regions of the first polycrystalline matrix.
- the specific identity and amount of activator incorporated inter stitially or into the lattice of the second semiconductor matrix for the establishment of luminescent centers can be selected according to several factors, including the chemical identity of the second semiconductor matrix and the desired color of electroluminescence.
- manganese activator is provided to a ZnS matrix in an amount up to about 4 atomic percent.
- the specific identity and amount of co-activator incorporated into the second semiconductor matrix can be selected according to several considerations, including the identities of the activator and second semiconductor matrix as well as the desired color and efficiency of electroluminescence.
- the second semiconductor matrix having activator and/or co-activator dispersed throughout can be an n-type semiconductor or a p-type semiconductor, depending on the identity of the activator and/or co-activator.
- manganese doped ZnS can provide an n-type semiconductor matrix.
- the second polycrystalline semiconductor matrix can have any thickness not inconsistent with the objectives of the present invention.
- the second semiconductor matrix for example, can have a thickness selected from Table II.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix are deposited by various thin film deposition techniques including atomic layer deposition (ALD), chemical vapor deposition (CVD) or physical vapor deposition (PVD). Suitable PVD methods can include sputtering or thermal evaporation.
- the first polycrystalline matrix in some embodiments, is deposited first on a suitable substrate, such as an electrode of the
- the second polycrystalline semiconductor matrix is subsequently deposited over the first polycrystalline matrix.
- the second polycrystalline semiconductor matrix is deposited first, followed by deposition of the first polycrystalline matrix.
- polycrystalline semiconductor matrix can be in direct contact with one another.
- one or more intermediate layer can be positioned between the first polycrystalline matrix and second polycrystalline semiconductor matrix.
- the intermediate layer(s) can be intrinsic semiconductor (i) to provide p-i-n architectures in the electroluminescent phase.
- atomic species are migrated in the first polycrystalline matrix by application of an electric field to the matrix.
- the migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions formed with the second polycrystalline semiconductor matrix.
- the electric field can be applied to the first polycrystalline matrix prior to deposition of the second polycrystalline semiconductor matrix. Alternatively, the electric field can be applied subsequent to deposition of the second polycrystalline semiconductor matrix over the first polycrystalline matrix.
- the electric field is applied by positioning the electroluminescent phase between first and second electrodes. There is no requirement that the first and second electrodes are commensurate with the front and back surface areas of the electroluminescent phase. The first and second electrodes, for example, may only partially cover surfaces of the electroluminescent phase.
- An alternating current (AC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
- a direct current (DC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
- Any strength of electric field suitable for migrating atomic species in the first polycrystalline matrix for the establishment of semiconducting regions described herein can be employed.
- electric field strength in some embodiments, is in the range of 10 3 V/m to 10 7 V/m.
- the electric field can be applied for any time period sufficient for semiconductor region formation. In some embodiments, the electric field is applied for a time period of 5 minutes to 5 hours. Shorter or longer electric field application times can be realized depending on several considerations including electric field strength and mobility of the migrating species in the first polycrystalline matrix. Additionally, the electric field can be applied to the first polycrystalline matrix at room temperature or elevated temperature.
- the electric field in some embodiments, is applied substantially parallel to the length of the first polycrystalline matrix. Application in a parallel direction permits migrating atomic species to move laterally or substantially laterally through the first polycrystalline matrix.
- substantially parallel electric field application inhibits driving migrating atomic species into the adjacent layer of second polycrystalline semiconductor matrix and promotes formation of semiconducting regions at the interface with the second polycrystalline semiconductor matrix, thereby providing p-n junctions of the electroluminescent phase.
- the semiconducting regions of the first polycrystalline matrix in some embodiments, do not migrate or substantially migrate during operation of the electroluminescent device.
- atomic species migrates atomic species from the first polycrystalline matrix into the adjacent second polycrystalline matrix.
- Migration of atomic species into the second polycrystalline semiconductor matrix can result in the formation of carrier injection structures in the second polycrystalline matrix.
- Migrating atomic species can aggregate or insert into the lattice and/or interstitial sites of the second polycrystalline semiconductor matrix to provide the carrier injection structures.
- Such carrier injection structures can form bulk p-n junctions with the second polycrystalline semiconductor matrix.
- cationic copper in some embodiments, can migrate into the second polycrystalline matrix of n-doped ZnS to form p-type carrier injection structures of Cu x S wherein x is from 1.8-2.0.
- First and second electrodes for application of the electric field can be independently selected from the group consisting of metals, alloys and electrically conducting radiation transmissive materials.
- Metals suitable for use as a first or second electrode can include aluminum, gold, copper, platinum, silver, nickel, iron or alloys thereof.
- Electrically conductive radiation transmissive materials are radiation transmissive conducting oxides. Radiation transmissive conducting oxides include indium tin oxide (ITO), gallium indium tin oxide (GITO), zinc indium tin oxide (ZITO), indium antimony oxide (IAO) and antimony tin oxide (ATO).
- First and second electrodes can have any thickness not inconsistent with the objectives of the present invention. In some embodiments, the first and second electrodes have a thickness ranging from 100 nm to 1 ⁇ .
- An electroluminescent device was constructed as follows. A quartz substrate was provided and a first electrode was deposited on a portion of the quartz substrate. To construct the first electrode, 10 nm of chromium was initially deposited by thermal evaporation followed by 190 nm of gold by thermal evaporation. An electron beam was employed for the thermal evaporation at a pressure on the order of 10 "5 torr. A first polycrystalline matrix of Cu x S was deposited over the first electrode and remainder of the quartz substrate by thermal evaporation of Cu 2 S powder. The deposited first polycrystalline matrix of Cu x S demonstrated a thickness of about 200 nm.
- a second polycrystalline semiconductor matrix of ZnS:Mn,Cl was deposited directly on the Cu x S polycrystalline matrix by thermal co-evaporation of ZnS:Mn,Cl powder and Mn to a thickness of about 200 nm. Thermal depositions of the Cu x S, ZnS:Mn,Cl and Mn were administered using resistive heating of the respective powders at a pressure on the order of 10 "6 mbar.
- electroluminescent phase was then annealed under vacuum of 10 " torr for 30 minutes at a temperature of 600°C.
- a gold second electrode was subsequently thermally deposited on a portion of the second ZnS:Mn,Cl polycrystalline semiconductor matrix.
- electroluminescent phase including the first Cu x S polycrystalline matrix.
- Application of the electric field migrated cationic copper in the first polycrystalline matrix forming p-type regions of Cu x S wherein x ranged from 1.8-2.0.
- the p-type regions formed p-n junctions with the n-type ZnS:Mn,Cl second polycrystalline matrix. These electroformed p-n junctions are evidenced in Figure 1.
- light emission was observed from the junctions when forward biased. Current provided to the light the devices was on the order to 100 mA. Dark regions at the interface of the first polycrystalline matrix and second polycrystalline
- semiconductor matrix may correspond to regions of the Cu x S matrix lacking sufficient copper for p-type formation. In some embodiments, these dark regions have experienced copper depletion resulting from copper migration in the applied electric field.
- a method of making a photovoltaic device comprises providing a photosensitive phase between a first electrode and second electrode, the photosensitive phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix.
- the migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junction of the photosensitive phase.
- the first polycrystalline matrix of the photosensitive phase can be of the formula M 1 X 1 , wherein Mi is selected from the group consisting of metallic elements including transition metals and Xi is selected from the group consisting of non-metallic elements of Groups IVA, VA and VIA of the Periodic Table.
- Mi for example, can be selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table.
- Mi is the sole migrating atomic species under the applied electric field.
- atomic species in addition to Mi may migrate, such as other cationic metallic atomic species and/or anionic species in the first polycrystalline matrix.
- migrating atomic species are not of the species forming the lattice of the first polycrystalline matrix.
- migrating atomic species can comprise cationic and/or anionic dopants such as cationic metals, halides or chalcogenides.
- the first polycrystalline semiconductor matrix can have any thickness not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix can be a light absorber for the photovoltaic device.
- the first polycrystalline matrix can be a light absorber for the photovoltaic device.
- the polycrystalline semiconductor matrix has a thickness sufficient for the efficient absorption of electromagnetic radiation.
- the first polycrystalline matrix for example, can have thickness selected from Table III.
- the first polycrystalline matrix of the photovoltaic device can comprise Cu x S.
- cationic Cu can be the migrating atomic species. Under the applied electric field, cationic Cu can migrate in the polycrystalline matrix forming regions of Cu x S having stoichiometry of p-type semiconductor.
- p-type regions of semiconducting Cu x S have a stoichiometry wherein x ranges from 1.8-2.
- Semiconducting regions of the first polycrystalline matrix can form p-n junctions with a layer of second polycrystalline semiconductor matrix adjacent to the first polycrystalline matrix.
- the second polycrystalline semiconductor matrix can be formed of compound semiconductor of opposite polarity of the semiconducting regions to form the p-n junctions.
- the second polycrystalline semiconductor matrix is of the formula M 2 X 2 , wherein M 2 is selected from the group consisting of metallic elements including transition metals and X 2 is selected from the group consisting of non-metallic elements of Groups IV A, VA and VIA of the Periodic Table.
- M 2 for example, can be selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table.
- the second polycrystalline semiconductor matrix can be formed of transition metal oxides, transition metal chalcogenides or transition metal halides.
- the second polycrystalline matrix for example, can be formed of n-type titania (Ti0 2 ).
- the second polycrystalline semiconductor matrix can have any thickness not inconsistent with the objectives of the present invention.
- the second semiconductor matrix for example, can have a thickness selected from Table IV.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention.
- the first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the
- polycrystalline semiconductor matrix are deposited by various thin film deposition techniques including atomic layer deposition (ALD), chemical vapor deposition (CVD) or physical vapor deposition (PVD). Suitable PVD methods can include sputtering or thermal evaporation.
- the first polycrystalline matrix in some embodiments, is deposited first on a suitable substrate, such as a first electrode of the electroluminescent device.
- the second polycrystalline semiconductor matrix is subsequently deposited over the first polycrystalline matrix.
- the second polycrystalline semiconductor matrix is deposited first, followed by deposition of the first polycrystalline matrix.
- the deposited first polycrystalline matrix and second polycrystalline semiconductor matrix can be in direct contact with one another.
- one or more intermediate layers can be positioned between the first polycrystalline matrix and second polycrystalline semiconductor matrix.
- the intermediate layer(s) can serve as buffer layers between the n-type and p-type materials.
- Buffer layer(s) for use in the photovoltaic device can be selected according to several considerations, including the chemical identities of the first polycrystalline matrix and second polycrystalline semiconductor matrix.
- the semiconducting regions of the first polycrystalline matrix can comprise Cu x S wherein x is from 1.8 to 2.0, and the second polycrystalline matrix is n-type Ti0 2 .
- buffer layer(s) of alumina and/or indium sulfide (In 2 S3) In 2 S3
- atomic species are migrated in the first polycrystalline matrix by application of an electric field to the matrix.
- the migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions formed with the second polycrystalline semiconductor matrix.
- the electric field can be applied to the first polycrystalline matrix prior to deposition of the second polycrystalline semiconductor matrix. Alternatively, the electric field can be applied subsequent to deposition of the second polycrystalline semiconductor matrix over the first polycrystalline matrix.
- the electric field is applied by positioning the photosensitive phase between first and second electrodes. There is no requirement that the first and second electrodes are commensurate with the front and back surface areas of the photosensitive phase.
- the first and second electrodes may only partially cover surfaces of the electroluminescent phase.
- An alternating current (AC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
- a direct current (DC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
- Any strength of electric field suitable for migrating atomic species in the first polycrystalline matrix for the establishment of semiconducting regions described herein can be employed.
- electric field strength in some embodiments, is in the range of 10 3 V/m to 10 7 V/m.
- the electric field can be applied for any time period sufficient for semiconductor region formation. In some embodiments, the electric field is applied for a time period of 5 minutes to 5 hours. Shorter or longer electric field application times can be realized depending on several considerations including electric field strength and mobility of the migrating species in the first polycrystalline matrix. Additionally, the electric field can be applied to the first polycrystalline matrix at room temperature or elevated temperature.
- the electric field in some embodiments, is applied substantially parallel to the length of the first polycrystalline matrix. Application in a parallel direction permits migrating atomic species to move laterally or substantially laterally through the first polycrystalline matrix.
- substantially parallel electric field application inhibits driving migrating atomic species into the adjacent layer of second polycrystalline semiconductor matrix and promotes formation of semiconducting regions at the interface with the second polycrystalline semiconductor matrix, thereby providing p-n junctions of the electroluminescent phase.
- semiconducting regions of the first polycrystalline matrix do not migrate during operation of the photovoltaic device.
- atomic species migrates atomic species from the first polycrystalline matrix into the adjacent second polycrystalline matrix.
- Migration of atomic species into the second polycrystalline semiconductor matrix can result in the formation of exciton pathway structures in the second polycrystalline matrix.
- Migrating atomic species can aggregate or insert into the lattice and/or interstitial sites of the second polycrystalline semiconductor matrix to provide the exciton pathway structures.
- Such exciton pathway structures can form bulk p-n junctions with the second polycrystalline semiconductor matrix.
- cationic copper in some embodiments, can migrate into the second polycrystalline matrix of n-type Ti0 2 to form p-type exciton pathways of Cu x S wherein x is from 1.8-2.0.
- First and second electrodes for application of the electric field can be independently selected from the group consisting of metals, alloys and electrically conducting radiation transmissive materials.
- Metals suitable for use as a first or second electrode can include aluminum, gold, copper, platinum, silver, nickel, iron or alloys thereof.
- Electrically conductive radiation transmissive materials are radiation transmissive conducting oxides. Radiation transmissive conducting oxides include indium tin oxide (ITO), gallium indium tin oxide (GITO), zinc indium tin oxide (ZITO), indium antimony oxide (IAO) and antimony tin oxide (ATO).
- First and second electrodes can have any thickness not inconsistent with the objectives of the present invention.
- the first and second electrodes have a thickness ranging from 100 nm to 1 ⁇ .
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Electroluminescent Light Sources (AREA)
Abstract
In one aspect, methods of making electroluminescent devices are described herein. A method described herein comprises providing an electroluminescent phase between a first electrode and second electrode, the electroluminescent phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the electroluminescent phase.
Description
OPTOELECTRONIC DEVICES AND APPLICATIONS THEREOF
RELATED APPLICATION DATA
The present application claims priority to United States Provisional Patent Application Serial Number 61/925,497 filed January 9, 2014 which is incorporated herein by reference in its entirety.
FIELD
The present invention relates to optoelectronic devices and, in particular, to
electroluminescent lighting devices. Photovoltaic devices are also described herein.
BACKGROUND
Currently available lighting systems include incandescent, fluorescent, halogen, and high intensity discharge sources of light. Disadvantages exist within lighting systems based on these illumination sources, many related to efficiency. Presently, only about 30% of the electrical energy consumed in lighting applications results in the production of light. The remainder of the electrical energy is dissipated by non-radiative processes such as heat generation. Incandescent light sources, for example, consume 45% of all lighting energy but only produce 14% of the total light generated. Moreover, fluorescent lamps are only about four times as efficient as incandescent sources and still suffer from inherent energy loss.
New lighting technologies are being developed in attempts to overcome the
disadvantages of current lighting systems. One such technology is based on light emitting diodes (LEDs). In general, light emitting diodes are constructed from semiconductor materials and, when forward biased, emit radiation. Depending on the semiconductor material used, the emitted radiation can fall within the ultraviolet, visible or infrared region of the electromagnetic spectrum. Light emitting diodes offer the advantages of enhanced lifetimes, reduced heat production, and rapid illumination times.
However, light emitting diodes require a direct current source for operation, which is fundamentally inconsistent with the alternating current provided by residential and commercial electrical outlets. As a result, various rectifier constructions are necessary to adapt present light emitting diodes to the alternating current sources found in residential and commercial lighting applications. The necessity of a rectifier increases production time and cost for lighting systems
incorporating light emitting diodes, thereby limiting widespread application of such lighting systems.
Electroluminescent devices compatible with alternating current sources have also been developed. These devices generally employ powder phosphor for light generation under an applied alternating electric field. While cost effective to produce, AC powder electroluminescent devices suffer dimming effects stemming from phosphor degradation. Additionally, phosphors can demonstrate widely heterogeneous micro structure further contributing to reduced light output. SUMMARY
In one aspect, methods of making electroluminescent devices are described herein which, in some embodiments, mitigate disadvantages of prior AC powder electroluminescent devices. A method described herein comprises providing an electroluminescent phase between a first electrode and second electrode, the electroluminescent phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the electroluminescent phase. For example, in some
embodiments, the migrating atomic species aggregate in one or more regions of the first polycrystalline matrix, such as in grain boundaries and/or at sites of crystalline defects.
Aggregation of the migrating atomic species renders these regions of the first polycrystalline matrix p-type or n-type semiconductor, wherein these semiconducting regions are constituents of p-n junctions of the electroluminescent phase.
In another aspect, methods of making photovoltaic devices are described herein. A method of making a photovoltaic device comprises providing a photosensitive phase between a first electrode and second electrode, the photosensitive phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the photosensitive phase. Further, the semiconducting regions can also function as light absorption regions of the photosensitive phase.
These and other embodiments are described in greater detail in the detailed description which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 illustrates light emission from p-n junctions of an electroluminescent device formed according to a method described herein.
DETAILED DESCRIPTION
Embodiments described herein can be understood more readily by reference to the following detailed description and examples and their previous and following descriptions. Elements, apparatus and methods described herein, however, are not limited to the specific embodiments presented in the detailed description and examples. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations will be readily apparent to those of skill in the art without departing from the spirit and scope of the invention.
I. Methods of Making Electroluminescent Devices
In one aspect, methods of making electroluminescent devices are described herein. A method described herein comprises providing an electroluminescent phase between a first electrode and second electrode, the electroluminescent phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the electroluminescent phase. For example, in some
embodiments, the migrating atomic species aggregate in one or more regions of the first polycrystalline matrix. Aggregation of the migrating atomic species renders these regions of the first polycrystalline matrix p-type or n-type semiconductor, wherein these semiconducting regions are constituents of p-n junctions of the electroluminescent phase.
The first polycrystalline matrix can be of the formula MiX], wherein Mi is selected from the group consisting of metallic elements including transition metals and Xi is selected from the group consisting of non-metallic elements of Groups IV A, VA and VIA of the Periodic Table.
M\, for example, can be selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table. Groups of the Periodic Table described herein are identified according to the CAS designation. In some embodiments, Mi is the sole migrating atomic species under the applied electric field. In other embodiments, atomic species in addition to Mi may migrate, such as other cationic metallic atomic species and/or anionic species in the first polycrystalline matrix. Alternatively, migrating atomic species are not of the species forming the lattice of the first polycrystalline matrix. In such embodiments, the migrating atomic species can comprise cationic and/or anionic dopants such as cationic metals, halides or chalcogenides.
The first polycrystalline matrix can have any thickness not inconsistent with the objectives of the present invention. In some embodiments, the first polycrystalline matrix can have thickness selected from Table I.
Table I - Thickness of First Polycrystalline Matrix
< 1 μηι
50 nm - 800 run
100 nm - 500 nm
75 nm - 300 nm
100 m - 200 nm
1 μηι As a non-limiting example, the first polycrystalline matrix can comprise CuxS. When the first polycrystalline matrix is formed of CuxS, cationic Cu can be the migrating atomic species. Under the applied electric field, cationic Cu can migrate in the polycrystalline matrix forming regions of CuxS having stoichiometry of p-type semiconductor. In such embodiments, p-type regions of semiconducting CuxS have a stoichiometry wherein x ranges from 1.8-2.
Semiconducting regions of the first polycrystalline matrix can form p-n junctions with a layer of second polycrystalline semiconductor matrix adjacent to the first polycrystalline matrix. The second polycrystalline semiconductor matrix can be formed of compound semiconductor of opposite polarity of the semiconducting regions to form the p-n junctions. In some
embodiments, the second polycrystalline semiconductor matrix is of the formula M2X2, wherein M2 is selected from the group consisting of metallic elements including transition metals and X2 is selected from the group consisting of non-metallic elements of Groups IVA, VA and VIA of
the Periodic Table. M2, for example, can be selected from metallic elements of Groups IB, IIB and III A of the Periodic Table.
Further, the second polycrystalline semiconductor matrix can comprise one or more dopants and/or luminescent centers for providing radiation recombination of carriers received from the semiconducting regions of the first polycrystalline matrix. Luminescent centers are sites or locations in the second semiconductor matrix where charge carriers are relaxed by one or more radiative pathways. Luminescent centers can include defects or trap states for localizing injected charge carriers for radiative recombination.
Luminescent centers can also include one or more atomic species doped or otherwise incorporated into the lattice and/or interstitial sites of the semiconductor matrix as an activator. Suitable activators include ions of transition metals, rare earth metals or mixtures thereof. In some embodiments, for example, activator of the second semiconductor matrix comprises one or more metal ions selected from Groups IB, IIIB, VIIB, VIIIB and IIIA of the Periodic Table. Activator, in some embodiments, comprises ions of copper, manganese, silver, gadolinium, dysprosium, europium, samarium, terbium or thulium or mixtures thereof.
Additionally, the second semiconductor matrix can further comprise co-activator chemical species. Co-activator chemical species work in conjunction with activator for the relaxation of carriers by one or more radiative pathways. Co-activator can comprise ionic species selected from Groups IIIA and VIIA of the Periodic Table. For example, co-activator can comprise ions of aluminum, indium, chlorine or iodine or mixtures thereof. In some embodiments, co-activator can be present in the second semiconductor matrix in the absence of activator. In such embodiments, the co-activator can assist in self-radiative relaxation processes of the second semiconductor matrix in response to carriers introduced by semiconducting regions of the first polycrystalline matrix.
The specific identity and amount of activator incorporated inter stitially or into the lattice of the second semiconductor matrix for the establishment of luminescent centers can be selected according to several factors, including the chemical identity of the second semiconductor matrix and the desired color of electroluminescence. In some embodiments, for example, manganese activator is provided to a ZnS matrix in an amount up to about 4 atomic percent. Moreover, the specific identity and amount of co-activator incorporated into the second semiconductor matrix
can be selected according to several considerations, including the identities of the activator and second semiconductor matrix as well as the desired color and efficiency of electroluminescence.
The second semiconductor matrix having activator and/or co-activator dispersed throughout can be an n-type semiconductor or a p-type semiconductor, depending on the identity of the activator and/or co-activator. For example, manganese doped ZnS can provide an n-type semiconductor matrix.
The second polycrystalline semiconductor matrix can have any thickness not inconsistent with the objectives of the present invention. The second semiconductor matrix, for example, can have a thickness selected from Table II.
Table II - Thickness of Second Polycrystalline Semiconductor Matrix
< 1 μπι
50 nm - 800 nm
100 nm - 500 nm
75 nm - 300 nm
100 nm - 200 nm
1 μπι
The first polycrystalline matrix and second polycrystalline semiconductor matrix can be deposited by any method not inconsistent with the objectives of the present invention. In some embodiments, the first polycrystalline matrix and second polycrystalline semiconductor matrix are deposited by various thin film deposition techniques including atomic layer deposition (ALD), chemical vapor deposition (CVD) or physical vapor deposition (PVD). Suitable PVD methods can include sputtering or thermal evaporation. The first polycrystalline matrix, in some embodiments, is deposited first on a suitable substrate, such as an electrode of the
electroluminescent device. The second polycrystalline semiconductor matrix is subsequently deposited over the first polycrystalline matrix. Alternatively, the second polycrystalline semiconductor matrix is deposited first, followed by deposition of the first polycrystalline matrix.
In some embodiments, the deposited first polycrystalline matrix and second
polycrystalline semiconductor matrix can be in direct contact with one another. In other embodiments, one or more intermediate layer can be positioned between the first polycrystalline matrix and second polycrystalline semiconductor matrix. In such embodiments, the intermediate
layer(s) can be intrinsic semiconductor (i) to provide p-i-n architectures in the electroluminescent phase.
As described herein, atomic species are migrated in the first polycrystalline matrix by application of an electric field to the matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions formed with the second polycrystalline semiconductor matrix. The electric field can be applied to the first polycrystalline matrix prior to deposition of the second polycrystalline semiconductor matrix. Alternatively, the electric field can be applied subsequent to deposition of the second polycrystalline semiconductor matrix over the first polycrystalline matrix. The electric field is applied by positioning the electroluminescent phase between first and second electrodes. There is no requirement that the first and second electrodes are commensurate with the front and back surface areas of the electroluminescent phase. The first and second electrodes, for example, may only partially cover surfaces of the electroluminescent phase.
An alternating current (AC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix. Moreover, a direct current (DC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix. Any strength of electric field suitable for migrating atomic species in the first polycrystalline matrix for the establishment of semiconducting regions described herein can be employed. For example, electric field strength, in some embodiments, is in the range of 103 V/m to 107 V/m. Further, the electric field can be applied for any time period sufficient for semiconductor region formation. In some embodiments, the electric field is applied for a time period of 5 minutes to 5 hours. Shorter or longer electric field application times can be realized depending on several considerations including electric field strength and mobility of the migrating species in the first polycrystalline matrix. Additionally, the electric field can be applied to the first polycrystalline matrix at room temperature or elevated temperature.
The electric field, in some embodiments, is applied substantially parallel to the length of the first polycrystalline matrix. Application in a parallel direction permits migrating atomic species to move laterally or substantially laterally through the first polycrystalline matrix.
Further, substantially parallel electric field application inhibits driving migrating atomic species into the adjacent layer of second polycrystalline semiconductor matrix and promotes formation of semiconducting regions at the interface with the second polycrystalline semiconductor matrix,
thereby providing p-n junctions of the electroluminescent phase. Once formed, the semiconducting regions of the first polycrystalline matrix, in some embodiments, do not migrate or substantially migrate during operation of the electroluminescent device.
Application of the electric field, in some embodiments, migrates atomic species from the first polycrystalline matrix into the adjacent second polycrystalline matrix. Migration of atomic species into the second polycrystalline semiconductor matrix can result in the formation of carrier injection structures in the second polycrystalline matrix. Migrating atomic species can aggregate or insert into the lattice and/or interstitial sites of the second polycrystalline semiconductor matrix to provide the carrier injection structures. Such carrier injection structures, in some embodiments, can form bulk p-n junctions with the second polycrystalline semiconductor matrix. For example, cationic copper, in some embodiments, can migrate into the second polycrystalline matrix of n-doped ZnS to form p-type carrier injection structures of CuxS wherein x is from 1.8-2.0.
First and second electrodes for application of the electric field can be independently selected from the group consisting of metals, alloys and electrically conducting radiation transmissive materials. Metals suitable for use as a first or second electrode can include aluminum, gold, copper, platinum, silver, nickel, iron or alloys thereof. Electrically conductive radiation transmissive materials, in some embodiments, are radiation transmissive conducting oxides. Radiation transmissive conducting oxides include indium tin oxide (ITO), gallium indium tin oxide (GITO), zinc indium tin oxide (ZITO), indium antimony oxide (IAO) and antimony tin oxide (ATO). First and second electrodes can have any thickness not inconsistent with the objectives of the present invention. In some embodiments, the first and second electrodes have a thickness ranging from 100 nm to 1 μιτι. EXAMPLE
An electroluminescent device was constructed as follows. A quartz substrate was provided and a first electrode was deposited on a portion of the quartz substrate. To construct the first electrode, 10 nm of chromium was initially deposited by thermal evaporation followed by 190 nm of gold by thermal evaporation. An electron beam was employed for the thermal evaporation at a pressure on the order of 10"5 torr. A first polycrystalline matrix of CuxS was deposited over the first electrode and remainder of the quartz substrate by thermal evaporation of
Cu2S powder. The deposited first polycrystalline matrix of CuxS demonstrated a thickness of about 200 nm. A second polycrystalline semiconductor matrix of ZnS:Mn,Cl was deposited directly on the CuxS polycrystalline matrix by thermal co-evaporation of ZnS:Mn,Cl powder and Mn to a thickness of about 200 nm. Thermal depositions of the CuxS, ZnS:Mn,Cl and Mn were administered using resistive heating of the respective powders at a pressure on the order of 10"6 mbar. The first CuxS polycrystalline matrix and second ZnS:Mn,Cl polycrystalline
semiconductor matrix constituted the electroluminescent phase of the device. The
electroluminescent phase was then annealed under vacuum of 10" torr for 30 minutes at a temperature of 600°C. A gold second electrode was subsequently thermally deposited on a portion of the second ZnS:Mn,Cl polycrystalline semiconductor matrix.
A DC electric field having field strength of about 105 Vm"1 was applied to the
electroluminescent phase including the first CuxS polycrystalline matrix. Application of the electric field migrated cationic copper in the first polycrystalline matrix forming p-type regions of CuxS wherein x ranged from 1.8-2.0. The p-type regions formed p-n junctions with the n-type ZnS:Mn,Cl second polycrystalline matrix. These electroformed p-n junctions are evidenced in Figure 1. As illustrated in Figure 1 , light emission was observed from the junctions when forward biased. Current provided to the light the devices was on the order to 100 mA. Dark regions at the interface of the first polycrystalline matrix and second polycrystalline
semiconductor matrix may correspond to regions of the CuxS matrix lacking sufficient copper for p-type formation. In some embodiments, these dark regions have experienced copper depletion resulting from copper migration in the applied electric field.
II. Methods of Making Photovoltaic Devices
In another aspect, methods of making photovoltaic devices are described herein. A method of making a photovoltaic device comprises providing a photosensitive phase between a first electrode and second electrode, the photosensitive phase comprising a layer of first polycrystalline matrix and migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junction of the photosensitive phase.
The first polycrystalline matrix of the photosensitive phase can be of the formula M1X1, wherein Mi is selected from the group consisting of metallic elements including transition metals and Xi is selected from the group consisting of non-metallic elements of Groups IVA, VA and VIA of the Periodic Table. Mi, for example, can be selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table. In some embodiments, Mi is the sole migrating atomic species under the applied electric field. In other embodiments, atomic species in addition to Mi may migrate, such as other cationic metallic atomic species and/or anionic species in the first polycrystalline matrix. Alternatively, migrating atomic species are not of the species forming the lattice of the first polycrystalline matrix. In such embodiments, migrating atomic species can comprise cationic and/or anionic dopants such as cationic metals, halides or chalcogenides.
The first polycrystalline semiconductor matrix can have any thickness not inconsistent with the objectives of the present invention. As described herein, the first polycrystalline matrix can be a light absorber for the photovoltaic device. In such embodiments, the first
polycrystalline semiconductor matrix has a thickness sufficient for the efficient absorption of electromagnetic radiation. The first polycrystalline matrix, for example, can have thickness selected from Table III.
Table III - Thickness of First Polycrystalline Matrix
< 1 μιη
50 nm - 800 nm
100 nm - 500 nm
75 nm - 300 nm
100 nm - 200 nm
> 1 μηι As a non-limiting example, the first polycrystalline matrix of the photovoltaic device can comprise CuxS. When the first polycrystalline matrix is formed of CuxS, cationic Cu can be the migrating atomic species. Under the applied electric field, cationic Cu can migrate in the polycrystalline matrix forming regions of CuxS having stoichiometry of p-type semiconductor. In such embodiments, p-type regions of semiconducting CuxS have a stoichiometry wherein x ranges from 1.8-2.
Semiconducting regions of the first polycrystalline matrix can form p-n junctions with a layer of second polycrystalline semiconductor matrix adjacent to the first polycrystalline matrix.
The second polycrystalline semiconductor matrix can be formed of compound semiconductor of opposite polarity of the semiconducting regions to form the p-n junctions. In some
embodiments, the second polycrystalline semiconductor matrix is of the formula M2X2, wherein M2 is selected from the group consisting of metallic elements including transition metals and X2 is selected from the group consisting of non-metallic elements of Groups IV A, VA and VIA of the Periodic Table. M2, for example, can be selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table. The second polycrystalline semiconductor matrix can be formed of transition metal oxides, transition metal chalcogenides or transition metal halides. The second polycrystalline matrix, for example, can be formed of n-type titania (Ti02).
The second polycrystalline semiconductor matrix can have any thickness not inconsistent with the objectives of the present invention. The second semiconductor matrix, for example, can have a thickness selected from Table IV.
Table IV - Thickness of Second Polycrystalline Semiconductor Matrix
≤ 1 μηι
50 nm - 800 nm
100 nm - 500 nm
75 nm - 300 nm
100 nm - 200 nm
≥ 1 μηι
The first polycrystalline matrix and second polycrystalline semiconductor matrix of the photovoltaic device can be deposited by any method not inconsistent with the objectives of the present invention. In some embodiments, the first polycrystalline matrix and second
polycrystalline semiconductor matrix are deposited by various thin film deposition techniques including atomic layer deposition (ALD), chemical vapor deposition (CVD) or physical vapor deposition (PVD). Suitable PVD methods can include sputtering or thermal evaporation. The first polycrystalline matrix, in some embodiments, is deposited first on a suitable substrate, such as a first electrode of the electroluminescent device. The second polycrystalline semiconductor matrix is subsequently deposited over the first polycrystalline matrix. Alternatively, the second polycrystalline semiconductor matrix is deposited first, followed by deposition of the first polycrystalline matrix.
In some embodiments, the deposited first polycrystalline matrix and second polycrystalline semiconductor matrix can be in direct contact with one another. In other embodiments, one or more intermediate layers can be positioned between the first polycrystalline matrix and second polycrystalline semiconductor matrix. In such embodiments, the intermediate layer(s) can serve as buffer layers between the n-type and p-type materials. Buffer layer(s) for use in the photovoltaic device can be selected according to several considerations, including the chemical identities of the first polycrystalline matrix and second polycrystalline semiconductor matrix. As described herein, the semiconducting regions of the first polycrystalline matrix can comprise CuxS wherein x is from 1.8 to 2.0, and the second polycrystalline matrix is n-type Ti02. In this embodiment, buffer layer(s) of alumina and/or indium sulfide (In2S3).
As described herein, atomic species are migrated in the first polycrystalline matrix by application of an electric field to the matrix. The migrating atomic species form semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions formed with the second polycrystalline semiconductor matrix. The electric field can be applied to the first polycrystalline matrix prior to deposition of the second polycrystalline semiconductor matrix. Alternatively, the electric field can be applied subsequent to deposition of the second polycrystalline semiconductor matrix over the first polycrystalline matrix. The electric field is applied by positioning the photosensitive phase between first and second electrodes. There is no requirement that the first and second electrodes are commensurate with the front and back surface areas of the photosensitive phase. The first and second electrodes, for example, may only partially cover surfaces of the electroluminescent phase.
An alternating current (AC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix. Moreover, a direct current (DC) voltage can be provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix. Any strength of electric field suitable for migrating atomic species in the first polycrystalline matrix for the establishment of semiconducting regions described herein can be employed. For example, electric field strength, in some embodiments, is in the range of 103 V/m to 107 V/m. Further, the electric field can be applied for any time period sufficient for semiconductor region formation. In some embodiments, the electric field is applied for a time period of 5 minutes to 5 hours. Shorter or longer electric field application times can be realized depending on several considerations including electric field strength and mobility of the
migrating species in the first polycrystalline matrix. Additionally, the electric field can be applied to the first polycrystalline matrix at room temperature or elevated temperature.
The electric field, in some embodiments, is applied substantially parallel to the length of the first polycrystalline matrix. Application in a parallel direction permits migrating atomic species to move laterally or substantially laterally through the first polycrystalline matrix.
Further, substantially parallel electric field application inhibits driving migrating atomic species into the adjacent layer of second polycrystalline semiconductor matrix and promotes formation of semiconducting regions at the interface with the second polycrystalline semiconductor matrix, thereby providing p-n junctions of the electroluminescent phase. Once formed, the
semiconducting regions of the first polycrystalline matrix do not migrate during operation of the photovoltaic device.
Application of the electric field, in some embodiments, migrates atomic species from the first polycrystalline matrix into the adjacent second polycrystalline matrix. Migration of atomic species into the second polycrystalline semiconductor matrix can result in the formation of exciton pathway structures in the second polycrystalline matrix. Migrating atomic species can aggregate or insert into the lattice and/or interstitial sites of the second polycrystalline semiconductor matrix to provide the exciton pathway structures. Such exciton pathway structures, in some embodiments, can form bulk p-n junctions with the second polycrystalline semiconductor matrix. For example, cationic copper, in some embodiments, can migrate into the second polycrystalline matrix of n-type Ti02 to form p-type exciton pathways of CuxS wherein x is from 1.8-2.0.
First and second electrodes for application of the electric field can be independently selected from the group consisting of metals, alloys and electrically conducting radiation transmissive materials. Metals suitable for use as a first or second electrode can include aluminum, gold, copper, platinum, silver, nickel, iron or alloys thereof. Electrically conductive radiation transmissive materials, in some embodiments, are radiation transmissive conducting oxides. Radiation transmissive conducting oxides include indium tin oxide (ITO), gallium indium tin oxide (GITO), zinc indium tin oxide (ZITO), indium antimony oxide (IAO) and antimony tin oxide (ATO). First and second electrodes can have any thickness not inconsistent with the objectives of the present invention. In some embodiments, the first and second electrodes have a thickness ranging from 100 nm to 1 μηι.
Various embodiments of the invention have been described in fulfillment of the various objectives of the invention. It should be recognized that these embodiments are merely illustrative of the principles of the present invention. Numerous modifications and adaptations thereof will be readily apparent to those skilled in the art without departing from the spirit and scope of the invention.
Claims
1. A method of making an electroluminescent device comprising:
providing an electroluminescent phase between a first electrode and a second electrode, the electroluminescent phase comprising a layer of first polycrystalhne matrix; and
migrating an atomic species in the first polycrystalhne matrix by application of an electric field to the first polycrystalhne matrix, the migrating atomic species forming semiconducting regions in the first polycrystalhne matrix, the semiconducting regions constituents of p-n junctions of the electroluminescent phase.
2. The method of claim 1 , wherein the p-n junctions are formed of the semiconducting regions of the first polycrystalhne matrix and a layer of second polycrystalhne semiconductor matrix adjacent to the first polycrystalhne matrix.
3. The method of claim 2, wherein the first polycrystalhne matrix is of the formula MjXj , and the second polycrystalhne semiconductor matrix is M2X2, wherein Mi and M2 are independently selected from the group consisting of transition metals and Xj and X2 are independently selected from the group consisting of non-metallic elements of Groups IVA, VA and VIA of the Periodic Table.
4. The method of claim 3, wherein Mi and M2 are independently selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table.
5. The method of claim 4, wherein the migrating atomic species is Mi.
6. The method of claim 5, wherein M\X\ is CuxS, and the semiconducting regions are p- type CuxS wherein x ranges from 1.8 to 2.
7. The method of claim 1 , wherein the semiconducting regions are localized to grain boundaries in the first polycrystalhne matrix.
8. The method of claim 1 , wherein an AC voltage is provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
9. The method of claim 1 , wherein a DC voltage is provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
10. The method of claim 1, wherein strength of the applied electric field ranges from
103 Vm^ to 107 Vm"1.
11. The method of claim 1 , wherein the layer of first polycrystalline matrix has a thickness of less than about 1 μιη.
12. The method of claim 1, wherein the electric field is applied to the first polycrystalline matrix at room temperature.
13. The method of claim 1 , wherein the electric field is applied to the first polycrystalline matrix at elevated temperature.
14. The method of claim 1 , wherein the electric field is applied for a time period of 5 minutes to 5 hours to form the semiconducting regions.
15. The method of claim 14, wherein the electric field is applied for a time period of 10 minutes to 1 hour to form the semiconducting regions.
16. The method of claim 1 , wherein the semiconducting regions do not migrate in the first polycrystalline matrix during operation of the electroluminescent device.
17. A method of making an photovoltaic device comprising:
providing an photosensitive phase between a first electrode and a second electrode, the photosensitive phase comprising a layer of first polycrystalline matrix; and
migrating an atomic species in the first polycrystalline matrix by application of an electric field to the first polycrystalline matrix, the migrating atomic species forming semiconducting regions in the first polycrystalline matrix, the semiconducting regions constituents of p-n junctions of the photosensitive phase.
18. The method of claim 17, wherein the p-n junctions are formed of the semiconducting regions of the first polycrystalline matrix and a layer of second polycrystalline semiconductor matrix adjacent to the first polycrystalline matrix.
19. The method of claim 18 , wherein the first polycrystalline matrix is of the formula Mi¾, and the second polycrystalline semiconductor matrix is M2X2, wherein Mi and M2 are independently selected from the group consisting of transition metals and Xi and X2 are independently selected from the group consisting of non-metallic elements of Groups IV A, VA and VIA of the Periodic Table.
20. The method of claim 19, wherein Mi and M2 are independently selected from metallic elements of Groups IB, IIB and IIIA of the Periodic Table.
21. The method of claim 20, wherein the migrating atomic species is Mi,
22. The method of claim 21 , wherein M\X\ is CuxS, and the semiconducting regions are p- type CuxS wherein x ranges from 1.8 to 2.
23. The method of claim 17, wherein the semiconducting regions are localized to grain boundaries in the first polycrystalline matrix.
24. The method of claim 17, wherein an AC voltage is provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
25. The method of claim 17, wherein a DC voltage is provided to the first and second electrodes to apply the electric field to the first polycrystalline matrix.
26. The method of claim 17, wherein strength of the applied electric field ranges from 103 Vm"1 to 107 Vm"1.
27. The method of claim 17, wherein the layer of first poly crystalline matrix has a thickness of less than about 1 μπι.
28. The method of claim 17, wherein the electric field is applied to the first polycrystallme matrix at room temperature.
29. The method of claim 17, wherein the electric field is applied to the first polycrystallme matrix at elevated temperature.
30. The method of claim 17, wherein the electric field is applied for a time period of 5 minutes to 5 hours to form the semiconducting regions.
31. The method of claim 30, wherein the electric field is applied for a time period of 10 minutes to 1 hour to form the semiconducting regions.
32. The method of claim 17, wherein the semiconducting regions do not migrate in the first polycrystallme matrix during operation of the photovoltaic device.
33. The method of claim 17, wherein the semiconducting regions absorb electromagnetic radiation incident on the photosensitive phase.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201461925497P | 2014-01-09 | 2014-01-09 | |
US61/925,497 | 2014-01-09 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2015106061A1 true WO2015106061A1 (en) | 2015-07-16 |
Family
ID=53524353
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2015/010758 WO2015106061A1 (en) | 2014-01-09 | 2015-01-09 | Optoelectronic devices and applications thereof |
Country Status (1)
Country | Link |
---|---|
WO (1) | WO2015106061A1 (en) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050151465A1 (en) * | 2001-05-25 | 2005-07-14 | Filippo Degli Azzoni Avogadro Carradori | Electroluminescence system and device for the production thereof |
US20100283045A1 (en) * | 2007-12-28 | 2010-11-11 | Hideki Uchida | Organic electroluminescent element |
US20110080090A1 (en) * | 2009-05-07 | 2011-04-07 | Massachusetts Institute Of Technology | Light emitting device including semiconductor nanocrystals |
US20130213461A1 (en) * | 2010-02-22 | 2013-08-22 | Mitsunaga Saito | Photovoltaic cell and method for manufacturing the same |
WO2013171659A1 (en) * | 2012-05-14 | 2013-11-21 | Koninklijke Philips Electronics N.V. | Electroluminescent compound comprising a metal-organic framework |
-
2015
- 2015-01-09 WO PCT/US2015/010758 patent/WO2015106061A1/en active Application Filing
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050151465A1 (en) * | 2001-05-25 | 2005-07-14 | Filippo Degli Azzoni Avogadro Carradori | Electroluminescence system and device for the production thereof |
US20100283045A1 (en) * | 2007-12-28 | 2010-11-11 | Hideki Uchida | Organic electroluminescent element |
US20110080090A1 (en) * | 2009-05-07 | 2011-04-07 | Massachusetts Institute Of Technology | Light emitting device including semiconductor nanocrystals |
US20130213461A1 (en) * | 2010-02-22 | 2013-08-22 | Mitsunaga Saito | Photovoltaic cell and method for manufacturing the same |
WO2013171659A1 (en) * | 2012-05-14 | 2013-11-21 | Koninklijke Philips Electronics N.V. | Electroluminescent compound comprising a metal-organic framework |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8093604B2 (en) | Engineered structure for solid-state light emitters | |
US7868351B2 (en) | Light emitting device | |
US6917158B2 (en) | High-qualty aluminum-doped zinc oxide layer as transparent conductive electrode for organic light-emitting devices | |
CN102800780A (en) | Electrogenerated infrared luminescent device and preparation method thereof | |
WO2015106061A1 (en) | Optoelectronic devices and applications thereof | |
US7923288B2 (en) | Zinc oxide thin film electroluminescent devices | |
JP2008091754A (en) | Light emitting element | |
CN114122272A (en) | Composite material and electroluminescent device | |
JP2010050421A (en) | Semiconductor | |
CN111490139A (en) | Composite electrode structure and light emitting device | |
US20090186243A1 (en) | Inorganic phosphor | |
KR102199543B1 (en) | Inorganic electroluminescent device comprising luminescent particle surrounded by a coating layer and method for producing same | |
JPH04363892A (en) | Dc electroluminescence element | |
JP5046637B2 (en) | Inorganic electroluminescent device | |
JP5130996B2 (en) | Light emitting element | |
JP5062882B2 (en) | Inorganic electroluminescence device | |
US20110140594A1 (en) | Inorganic electroluminescent device | |
JP2009298902A (en) | Inorganic phosphor | |
JP2009170358A (en) | Inorganic el element | |
KR20230127679A (en) | Low-voltage visible emitting device based on metal-oxide-semiconductor structure and the Manufacturing Method | |
JP2010031154A (en) | Inorganic phosphor | |
RU2479070C2 (en) | Light-emitting diode light source | |
JP2010182490A (en) | Light-emitting device | |
JP2009215450A (en) | Inorganic phosphor | |
JP2007123221A (en) | Electron hole injection controlled zinc sulfide el device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 15734880 Country of ref document: EP Kind code of ref document: A1 |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
32PN | Ep: public notification in the ep bulletin as address of the adressee cannot be established |
Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 112(1) EPC (EPO FORM 1205A DATED 25.10.2016) |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 15734880 Country of ref document: EP Kind code of ref document: A1 |