184results about How to "Lower energy gap" patented technology

The present invention is related to a depletion or enhancement mode metal transistor in which the channel regions of a transistor device comprises a thin film metal or metal composite layer formed over an insulating substrate.

Disclosed is a GaN LED structure with a p-type contacting layer using Al—Mg-codoped In1−yGayN grown at low temperature, and having low resistivity. The LED structure comprises, from the bottom to top, a substrate, a buffer layer, an n-type GaN layer, an active layer, a p-type shielding layer, and a p-type contacting layer. In this invention, Mg and Al are used to co-dope the In1−yGayN to grow a low resistive p-type contacting layer at low temperature. Because of the Al—Mg-codoped, the light absorption problem of the p-type In1−yGayN layer is improved. The product, not only has the advantage of convenience of the p-type contacting layer for being manufactured at low temperature, but also shows good electrical characteristics and lowers the operating voltage of the entire element so that the energy consumption during operation is reduced and the yield rate is increased.

The invention discloses an anthracene and benzothiadiazole copolymer, and a preparation method and application thereof. The anthracene and benzothiadiazole copolymer has a general molecular structure formula shown in (I), wherein R1 and R2 are selected from -H, substituted or unsubstituted C1-C40 alkyl, substituted or unsubstituted aryl, and substituted or unsubstituted heteroaryl, cyano or halogen; R3 and R4 are selected from -H, substituted or unsubstituted C1-C40 alkyl, substituted or unsubstituted C1-C40 alkoxy, substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C6-C40arylalkyl, and substituted or unsubstituted C6-C40 alkoxy or cyano; n is the polymerization degree and is a natural number ranging from 1 to 500; and Ar is an organic group with an electron donating property. The anthracene and benzothiadiazole copolymer disclosed by the invention has the advantages of low energy gap, high carrier mobility and wide spectral absorption range, and improves the photoelectric conversion efficiency. The preparation method of the anthracene and benzothiadiazole copolymer is simple in process, high in product yield, and easy to operate and control.

The present invention relates to a benzodithiophene based copolymer containing thieno[3,4-b]thiophene units and a preparing method and applications thereof. The polymer has a structural formula (I), wherein R1 and R2 are respectively selected from H, and alkyl groups of C1 to C16; R3 and R4 are respectively selected from H, alkyl groups of C1 to C16, alkoxy groups of C1 to C16, or thiophene groups substituted by alkyl groups of C1 to C16; R5 is selected from alkyl groups of C1 to C16; n is a natural number from 7 to 80. Applications of the benzodithiophene based copolymer containing thieno[3,4-b]thiophene units in polymer solar cells, polymer organic light-emission, polymer organic field effect transistors, polymer organic optical storage, polymer organic nonlinear materials or polymer organic laser are also provided.

The invention relates to a conjugated polymer represented by the formula (P); wherein the R1 represents an alkyl group with a carbon number of 6 to 15, the R2 represents an H atom or an alkyl group with a carbon number of 1 to 16, the R3 represents an alkyl group with a carbon number of 1 to 17, and n is a natural number in a range of 5 to 60. The invention also relates to a preparation method and applications of the conjugated polymer. An acyl group is introduced into the a-position on one thiophene ring of benzotrithiophene, and then the length of alkanoyl can be adjusted so as to modulate the solubility and electron density of the conjugated polymer. Dithienobenzooxadiazole is an excellent electron acceptor unit. Benzotrithiophene is taken as the donor unit, an electron pushing-pulling effect between the donor unit and the strong electron acceptor unit (dithienobenzooxadiazole) reduces the energy gap of the conjugated polymer, and thus the light absorption range of the conjugated polymer is largely increased.

Provided are an organic EL device which is practically satisfactory in terms of a light-emitting characteristic, a driving voltage, and durability, and a compound for organic EL devices to be used in the device. The organic EL device is an organic EL device produced by laminating, on a substrate, an anode, a plurality of organic layers including a light-emitting layer, and a cathode, the organic EL device containing, in at least one organic layer selected from the light-emitting layer, a hole-transporting layer, an electron-transporting layer, a hole-blocking layer, and an electron-blocking layer, a boron compound having two indolocarbazolyl groups in a molecule thereof. The boron compound is represented by Y-L-B(A)a-L-Y or Y-L(Z)b-Y, where Y represents an indolocarbazolyl group, L represents an aromatic group, and Z represents a boron-containing group.

An organic electroluminescence device comprising a cathode, an anode and at least one layer comprising a phosphorescent light emitting material and a host material which is sandwiched between the cathode and the anode and further comprising an electron injecting layer which is adhered to the light emitting layer and is capable of transporting electrons, wherein an ionization potential of the host material is 5.9 eV or smaller, and wherein an energy gap of the electron transporting material in the electron injecting layer is smaller than that of the host material in the light emitting layer or wherein a triplet energy of the electron transporting material in the electron injecting layer is smaller than that of the host material in the light emitting layer. It emits phosphorescent light with enhanced efficiency because it comprises a light emitting layer and an electron injecting layer both satisfying specified condition and employs a light emitting layer capable of electron transporting.