Nippondenso Co., Ltd.

Denso Corporation

Research Development Corporation of Japan

Kabushiki Kaisha Toyota Chuo Kenkyusho

Research Development Corporation

Nippondenso Corporation

Masayuki Katayama

Nobuei Ito

Tadashi Hattori

Atsushi Mizutani

Akira Kato

Kazuhiko Sugiura

Yutaka Hattori

Takashi Inoue

Hajime Ishihara

Hiroshi Kondo

Masahiko Osada

Kazuhiro Inoguchi

Koji Noda

Tomohiko Mori

Tomoya Uchida

Kazushige Kojima

Hirotaka Suzuki

Tetsuya Katoh

Akito Toyoda

Kunio Akedo

Yoshihiro Kikuzawa

Yasuo Yamamoto

Koujirou Tachi

Toshikazu Satoh

Koichi Sakaguchi

The organic electroluminescence display device has a laminated portion on a base substrate. The device may have a cavernous portion formed by exploding a part of the laminated portion in a screening processing. A protective layer is formed to cover a whole surface of a wall defining the cavernous portion. Therefore, substances contained in the air are prevented from contacting to an organic electroluminescence layer at least partially defining the cavernous portion. Therefore, even if moisture is contained in the air, it is possible to prevent moisture from being absorbed by the organic electroluminescence layer. Moreover, since moisture is not absorbed by the organic electroluminescence layer, it is possible to reduce irregular spot on the device. In addition, it is possible to reduce a short circuit at an open defective portion.

Organic electroluminescence display device and method for manufacturing the same

There is provided a polymer or low-molecular-weight compound multilayer type organic EL device configured such that a light-emitting layer formed on a hole transport layer includes a mixture of a polymer material and a low-molecular weight material. With such a configuration, the low-molecular-weight material added to the polymer material serves as a binder filling the gap of the steric hindrance to form entanglement of the polymer material and the low-molecular-weight material. This results in that the interface between the hole transport layer and the light-emitting layer is an interface high in adhesion and also high in carrier injectability. Further, optimization of the formation conditions and materials can achieve still higher reliability and longer lifetime.

Organic luminescent device and manufacturing method thereof

An EL device includes a control unit that controls a driving circuit so that a plurality of EL elements emits light several times per driving cycle. Specifically, when a driving voltage is applied to the plurality of EL elements, the plurality of EL elements emits several times per driving cycle. As a result, since the amount of light integrated per time increases, the plurality of EL elements obtains high luminous power even if a plurality of El elements having a very short emission decay time is used.

Electroluminescent device with sufficient luminous power and driving method thereof

An EL element including a first electrode, a luminescent layer, an insulation layer, and a second electrode is laminated so that a short circuit between the first electrode and the second electrode at a defect of the insulation layer between the luminescent layer and the second electrode is prevented. A cavity is formed in the layer under an area at which the second insulation layer is missing. The second electrode is separated by the cavity from the first insulation layer located under the luminescent layer to prevent a short circuit.

EL element, method for forming EL element, and display panel that uses EL element

An EL device is constructed of an insulating substrate, and a first electrode, a first insulating layer, a luminescent layer, a second insulating layer and a second electrode, which are laminated on the insulating substrate in this order. The insulating layer is made by a method other than ALE, for example, sputtering or vapor deposition. The second insulating layer includes alternating layers of Al O and TiO , which are formed by ALE. The second insulating layer covers the luminescent layer and an end surface of the first insulating layer. Since the first insulating layer is not formed by ALE, the device can be manufactured with high productivity, and there is no less of performance compared to a device having two ALE insulation layers.

Electroluminescent device

Disclosed is a method of producing an electroluminescent (EL) device having a CaGa,S,:Ce luminescent layer. The ratio of the X-ray diffraction peak intensity I,for the (200) reflection of CaS to the X-ray diffraction peak intensity I,for the (400) reflection of CaGa,S,as appearing in the X-ray diffraction spectrum for the luminescent layer, I,/I,, is 0.1 or less. The amount of the impurity CaS in the luminescent layer is reduced. The EL device produces blue emission with high purity.

Sputtering method of producing and electroluminescent device with improved blue color purity

First and second insulating layers in an EL device are respectively composed of Al,O,/TiOx:Ba laminated layers. The Al,O,/TiOx:Ba laminated layers are formed by alternately laminating Al,O,layers and TiO,layers added with Ba by an ALE method. Adding Ba into the TiO,layers mitigates a change in resistivity thereof with respect to a change in temperature. As a result, the EL device provides an excellent voltage withstanding performance which is stable against the changes in the temperature.

Electroluminescent device and method of producing the same

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

An electroluminescent device improved in brightness is disclosed. The electroluminescent device comprising sequentially stacked layers having an optically transparent material on at least the viewing side of the structure comprises a luminescent layer based on a Group II-III-VI compound host material with an element acting as a luminescent center added therein, wherein a Group II element having an ion radius differing from that of the Group II element constituting the compound host material is further added in the luminescent layer.

Method for fabricating electroluminescent device

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

An electroluminescence element provided with a luminescent layer sandwiched between two electrodes on an insulating substrate. The luminescent layer is composed of zinc sulfide with a fluoride or a luminescent center element added, wherein the X-ray diffraction spectrum thereof has only a single peak at an X-ray diffraction angle from the luminescent layer, ranging from 25.degree. to 30.degree. according to a thin film X-ray diffraction measurement method using Cu-Kd radiation, and no other peaks of the X-ray diffraction spectrum exist at an X-ray diffraction angle of 27.degree..

Process for the production of electroluminescence element,

An electroluminescent element includes a glass substrate, on which are formed a first electrode, a first insulating layer, a first luminescent layer, a second luminescent layer, a second insulating layer, a second electrode, a protective film and a red color filter. In this structure, the first luminescent layer is made of ZnS having Mn added thereto, and the second luminescent layer is made of ZnS having Tb added thereto. Here, the clamp electric field intensity of the second luminescent layer is higher than that of the first luminescent layer, and the product of a dielectric constant and clamp electric field intensity of the first luminescent layer is larger than the product of a dielectric constant and clamp electric field intensity of the second luminescent layer. Consequently, it is possible to increase the luminance of light emitted from the luminescent layer and decrease the luminescence threshold voltage when the luminescent layer is made into a stacked layer structure.

Electroluminescent element

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.

Growing community of inventors

Handa, Japan

Masayuki Katayama