Nippondenso Co., Ltd.

Denso Corporation

Research Development Corporation of Japan

Research Development Corporation

Nisshinbo Micro Devices Inc.

Nippondenso Corporation

Atsushi Mizutani

Nobuei Ito

Masayuki Katayama

Tadashi Hattori

Yutaka Hattori

Akira Kato

Akihiko Teshigahara

Hideo Yamada

Hiroyuki Kuchiji

Naoki Masumoto

A piezo-electric element includes a piezo-electric element part, a support part, and a stretchable film. The piezo-electric element part includes a piezo-electric film and electrodes between which the piezo-electric film is sandwiched in a thickness direction. The support part supports a peripheral portion of the piezo-electric element part. The stretchable film is provided in an oscillation region located inside of the peripheral portion of the piezo-electric element part. The stretchable film also has a higher elasticity than that of the piezo-electric element part.

Piezo-electric element

In an EL device in which a blue light emitting material obtained by doping Ce as a luminescent center into CaGa.sub.X S.sub.Y host material is used for a luminescent layer, values of X and Y in the CaGa.sub.X S.sub.Y host material are set in ranges of 1.4.ltoreq.X.ltoreq.1.9, 2.9.ltoreq.Y.ltoreq.3.8. The blue light emitting material thus obtained has a new structure defined by the fact that an X-ray diffraction spectrum obtained by using Cu K.alpha. radiation as a X-ray source has at least one peak in diffraction angles of 13.5.+-.0.2 degree, 14.6.+-.0.2 degree and 25.7.+-.0.2 degree. The blue light emitting EL device has a luminance higher than that of a conventional EL device.

Blue light emitting material, electroluminescent device using same and

Fabrication of an electroluminescent device having a high-quality luminescent layer is disclosed. The device emits intense blue light. A first electrode layer, a first dielectric layer, the luminescent layer, a second dielectric layer, and a second electrode layer are successively formed on a glass substrate. At least the exit side of the device is made from an optically transparent material. A first gaseous source material of a group II element belonging to group II of the periodic table, a second gaseous source material of a group VIB element belonging to group VIB, and a third gaseous source material of an element forming the luminescent center of the luminescent layer are supplied into a reaction furnace through first, second, and third gas supply tubes, respectively, and caused to react with each other. Thus, the luminescent layer is formed by chemical vapor deposition. The first material acts as a base material from which the luminescent layer is formed. The first tube for the first material is laid in the center of the furnace. The third tube for the third material forming the luminescent center is laid around the first gas supply tube. The second tube is laid around the third tube.

Method and apparatus for fabricating electroluminescent device

A method and apparatus for manufacturing EL devices in a short period of time wherein during formation of a light emitting layer composed of II, III or VI-group of elements doped with a light emitting element through a chemical vapor deposition method, water content of a transport gas that transports gasified organic metals is removed through a dehydration filter and thus, source material decomposition due to the water content is prevented and a steady supply of source materials becomes possible. By removing the water content of the transport gas, source materials can be supplied constantly even if heating temperatures exceed a temperature conventionally regarded as the temperature at which decomposition starts and thus, a light emitting layer having a practical thickness can be formed in a short period of time. Because of the high-speed film formation, the rate of the film being contaminated with impurities lessens and the light emitting layer has a luminance three times that of conventional layers.

High-speed method for manufacturing an electroluminescent device using

In an EL device in which a blue light emitting material obtained by doping Ce as a luminescent center into Ca.sub.X S.sub.Y host material is used for a luminescent layer, values of X and Y in the CaGa.sub.X S.sub.Y host material are set in ranges of 1.4.ltoreq.X.ltoreq.1.9, 2.9.ltoreq.Y.ltoreq.3.8. The blue light emitting material thus obtained has a new structure defined by the fact that an X-ray diffraction spectrum obtained by using Cu K.alpha. radiation as a X-ray source has at least one peak in diffraction angles of 13.5.+-.0.2 degrees, 14.6.+-.0.2 degrees and 25.7.+-.0.2 degrees. The blue light emitting EL device has a luminance higher than that of a conventional EL device.

Electroluminescent device containing blue light emitting material

A luminescent layer in an EL device composed of CaGa.sub.2 S.sub.4 :Ce includes a first luminescent layer and a second luminescent layer. The first luminescent layer has an atomic ratio of Ga to Ca being higher than that in the second luminescent layer, and directly disposed on a first insulating layer, whereby delamination can be prevented. The atomic ratio of Ga to Ca in the second luminescent layer is approximately equal to a stoichiometric ratio, so that the threshold voltage of the EL device can be kept low.

Electroluminescent device and method for producing the same

An electroluminescence element including at least an insulating substrate, a first electrode, a first insulating layer, a luminescent layer having at least one side constructed and arranged to allow light to pass out of the electroluminescence element, a second insulating layer and a second electrode in this order in a stack, with the components on the at least one side of the luminescent layer being optically transparent. The luminescent layer includes a base material formed from a II-VI compound semiconductor, at least one rare earth element, and at least one halogen element substituted for a VI group element at a lattice site of the VI group element of the II-VI compound semiconductor and located in the vicinity of the at least one rare earth element. The luminescent layer has a luminescence spectrum in which, in addition to the original emission peaks of the at least one rare earth element, some of the original emission peaks have at least one split emission peak located within a 10 nm wavelength range thereof.

Electroluminescence element and process for fabricating same

An electroluminescence element comprises the luminescent layer having a luminescence spectrum in which, in addition to the original emission peaks of the rare earth element, one or more emission peaks exist within a 10 nm wavelength range around each of some original emission peak. The luminescent layer is of a compound semiconductor doped with a rare earth element, deposited by organic metal chemical vapor deposition in which source gases for the rare earth element and elements constituting the compound semiconductor, not containing any halogen element, are supplied to the vicinity of the insulating substrate, separately from halogen or hydrogen halide gas which is also supplied to the vicinity of the insulating substrate.

A thin-film EL display device of red luminescent color having high luminous intensity and high reliability is disclosed. The thin-film EL display device has a first transparent electrode, a first transparent insulating layer, a light-emitting layer of zinc sulfide (ZnS) with the addition of manganese (Mn), a red-light transmitting filter of amorphous silicon (a-Si), a second transparent insulating layer, and a second transparent electrode (second electrode), which are successively deposited one on top of another on a glass substrate. The EL display device produces red light from orange light emission from the light-emitting layer. High temperature resistance of the filter permits the insertion of the filter to a desired position during the fabrication process for the thin-film EL display device. Furthermore, since the filter characteristics of the thin-film EL display do not suffer degradation by the heat generated during the light emitting operation thereof, there is no concern for luminescent color deterioration with time.

Thin-film electroluminescence display device

A process for producing an electroluminescent device comprising a luminescent layer located between two electrodes formed on an insulating substrate wherein the luminescent layer is composed of a host material to which a luminescent center element is added and the host material is composed of an alkaline earth metal element of the Group II of the Periodic Table and an element of the Group VI, which process comprises forming the host material by chemical vapor deposition to react a gas of an organic compound containing the alkaline earth metal element of the Group II and a gas of a compound containing the element of the Group VI in a reactor, the gas of the organic compound containing the alkaline earth metal element of the Group II being formed from a cyclopentadienyl compound. By this process, EL devices can be produced with high reproducibility.

Growing community of inventors

Anjo, Japan

Atsushi Mizutani