City University of Hong Kong

Cityu Research Limited

Chinese Academy of Sciences

Shuit-Tong Lee

Chun-Sing Lee

Igor Bello

Wenjun Zhang

Peng-Fei Wang

You-Sheng Zou

Yat Ming Chong

Zhi-Qiang Gao

Pengfei Wang

Chun-sing Lee

Kar Man Leung

Bao-Xiu Mi

Wen-Jun Zhang

Kwok Leung Ma

Zhi-Yuan Xie

Na Li

Weimin Liu

Liang-sun Hung

Chun Sing Lee

Ning Wang

Baoxiu Mi

Fu-Lung Wong

Liang-Sun Hung

Zhiyuan Xie

Quan Li

He-qin Li

Zhen-Bo Deng

You-Shen Zou

William Alexander Gambling

Chi-Pui Li

Xu-Hui Sun

Qing Ye

Ning-Bew Wong

Shiu-Lun Lai

Boon-Keng Teo

Xin Jiang

Mei-Yee Chan

Chit Yiu Chan

Naigui Shang

A conical structure of cubic Boron Nitride (cBN) is formed on a diamond layered substrate. A method of forming the cBN structure includes steps of (a) forming diamond nuclei on a substrate, (b) growing a layer of diamond film on the substrate, (c) depositing a cBN film on said diamond layer, (d) pre-depositing nanoscale etching masks on the cBN film, and (e) etching the deposited cBN film. In particular, though not exclusively, the cubic Boron Nitride structure has great potential applications in probe analytical and testing techniques including scanning probe microscopy (SPM) and nanoindentation, nanomechanics and nanomachining in progressing microelectromechanical system (MEMS) and nanoelectyromechanical system (NEMS) devices, field electron emission, vacuum microelectronic devices, sensors and different electrode systems including those used in electrochemistry.

Method of fabrication of cubic boron nitride conical microstructures

There are disclosed rare-earth metal containing electron-injecting electrodes which are particularly effective for use with organic LED devices used in electroluminescent structures and which may in particular be formed as transparent electrodes for use in transparent or surface emitting OLEDs.

Organic electroluminescent devices formed with rare-earth metal containing cathode

A method for fabricating diamond nanopillars includes forming a diamond film on a substrate, depositing a metal mask layer on the diamond film, and etching the diamond film coated with the metal mask layer to form diamond nanopillars below the mask layer. The method may also comprise forming diamond nuclei on the substrate prior to forming the diamond film. Typically, a semiconductor substrate, an insulating substrate, a metal substrate, or an alloy substrate is used.

Method of making diamond nanopillars

Disclosed herein are several organic compounds having electron-transporting and/or hole-blocking performance and their preparation method and use and the OLEDs comprising the organic compound. The organic compounds exhibit high ionization potential (IP), electron affinity (Ea), glass transition temperature (Tg) and high electron mobility, and are a kind of good electron-transporting material with good hole-blocking ability. The devices comprising these compounds as one of the emitting layer, electron-transporting layer (ETL) and hole-blocking layer (HBL) show improved efficiency and better color purity.

Organic compound having electron-transporting and/or hole-blocking performance and its use and OLEDs comprising the compound

An electroluminescence device has an anode, a cathode and an emitting layer located between the anode and the cathode. The emitting layer contains a compound selected from a group consisting of neutral red and its derivatives.

Organic electroluminescence device

A multilayer coating (MLC) is composed of two chemically different layered nanocrystalline materials, nanodiamond (nanoD) and nano-cubic boron nitride (nono-cBN). The structure of the MLC and fabrication sequence of layered structure are disclosed. The base layer is preferably nanoD and is the first deposited layer serving as an accommodation layer on a pretreated substrate. It can be designed with a larger thickness whereas subsequent alternate nano-cBN and nanoD layers are typically prepared with a thickness of 2 to 100 nm. The thickness of these layers can be engineered for a specific use. The deposition of the nanoD layer, by either cold or thermal plasma CVD, is preceded by diamond nucleation on a pretreated and/or precoated substrate, which has the capacity to accommodate the MLC and provides excellent adhesion. Nano-cBN layers are directly grown on nanodiamond crystallites using ion-assisted physical vapor deposition (PVD) and ion-assisted plasma enhanced chemical vapor deposition (PECVD), again followed by nanodiamond deposition using CVD methods in cycles until the intended number of layers of the MLC is obtained.

Ultrahard multilayer coating comprising nanocrystalline diamond and nanocrystalline cubic boron nitride

Cubic boron nitride/diamond (cBND) composite films with excellent adherence to various substrates and their fabrication method are disclosed. The cBND composite confining cBN can be prepared without any amorphous/turbostratic BN (aBN/tBN) incubation layers. The cBND composite is established on the compatibility of structural and physical properties of two superior materials: cBN on top and diamond beneath. The underlying diamond is adapted to the substrate of choice using a variety of methods which may include prescratching the substrates, bias enhanced nucleation, etching for depleting undesirable chemical elements, construction of buffer layers and gradient buffer layers for the isolation of undesirable chemical elements or/and adaptation of physical properties. The diamond nuclei are preferably formed either by bias-enhanced nucleation or by pre-scratching the substrate prior to nucleation. The cBN films in cBND composites of the present invention can grow directly on the underlaying diamond films in heteroepitaxial relationships.

Cubic boron nitride/diamond composite layers

A surface acoustic wave (SAW) device which is made of cBN/diamond composite structures and the fabrication method are disclosed. In the SAW device based on cubic boron nitride and diamond composite structures, the diamond hard layer includes randomly-oriented polycrystalline diamond (poly-D), oriented (heteroepitaxial) diamond, single-crystal diamond wafers and nanocrystalline diamond (nano-D) films. The cBN film with a sound velocity close to that of diamond serves as the piezoelectric layer, which was directly deposited on diamond hard layer without any soft sp-BN incubation layer by ion assisted physical vapor deposition (PVD) and plasma-enhanced (or ion assisted) chemical vapor deposition (PECVD). Due to the high sound velocity and the low velocity dispersion between the cBN and diamond layered materials, the present SAW device based on cubic boron nitride and diamond composite structures can improve the device performance and operate at ultra-high frequency range.

Surface acoustic wave (SAW) devices based on cubic boron nitride/diamond composite structures

A compound of formula [I]:X&#x2014;R[I]wherein X represents the group: and R is either (i) represented by the formula [II] wherein n is 1 or 2, and the or each Rgroup is independently selected from the group consisting of hydrogen and halogen atoms, cyano, nitro, mercapto, carbonyl and sulfone groups, and optionally substituted alkyl, haloalkyl, hydroxyalkyl, aryl, alkoxy, aryloxy, alkylamino, arylamino, alkylthio, arylthio, ester, siloxy, cyclic hydrocarbon and heterocyclic groups;or (ii) is selected from the group consisting of optionally substituted alkyl, hydroxyalkyl, aryl, cyclic hydrocarbon and heterocyclic groups;wherein in each case R&#x2013;Rare each independently selected from the group consisting of hydrogen and halogen atoms, cyano, nitro, mercapto, carbonyl and sulfone groups, and optionally substituted alkyl, haloalkyl, hydroxyalkyl, aryl, alkoxy, aryloxy, alkylamino, arylamino, alkylthio, arylthio, ester, siloxy, cyclic hydrocarbon and heterocyclic groups. The compounds are useful as hole-transporting materials in electroluminescence devices.

Electroluminescent devices

A simple chemical technique has been developed to grow large quantity of carbon nanostructures, including carbon nanotubes, hydrocarbon nanotubes and carbon nanoonions, in the organic solution at ambient (room) temperature and atmospheric pressure using silicon nanostructures (nanowires, nanodots, ribbons, and porous silicon) as starting materials. These CNT and CNO have the lattice d-spacing from 3.4 &#x212b; to 5 &#x212b;.

Room temperature synthesis of multiwalled carbon nanostructures

Compounds of formula [I]wherein each Rto Ris independently selected from the group consisting of halogen atoms, cyano, isocyano, mercapto, amino, carbonyl, carboxy, sulfone, nitro and hydroxy groups, and optionally substituted alkyl, alkenyl, alkynyl, haloalkyl, hydroxyalkyl, aryl, alkoxy, aryloxy, alkylamino, arylamino, alkylarylamino, amide, alkylthio, arylthio, alkoxy carbonyl, siloxy, cyclic hydrocarbon or heterocyclic groups; each x is independently zero, one, two or three; each y is independently zero or one; and each z is independently zero, one, two or three are useful in organic electroluminescence devices. Such compounds are disclosed herein, as well as organic electroluminescence devices using the compounds in the emissive layer.

Red-emitting organic electroluminescent elements

An organic light-emitting diode is described in which the anode comprises midfrequency magnetron sputtered aluminum-doped zinc oxide to increase the device stability and to decrease the material cost. Due the novel deposition technique, ZnO:Al film with ITO-like electrical conductivity can be deposited and improved device performance, especially the long-term stability can be obtained which are attributed to the modification of the ZnO:Al conductivity and surface chemistry.

High-qualty aluminum-doped zinc oxide layer as transparent conductive electrode for organic light-emitting devices

The present invention deals with the generation of sharp single crystal diamond tips and the arrays of these tips, and their fabrication technology. The invention combines the deposition of synthetic diamond films with reactive etching processes. Upon the diamond orientation prepared and reactive etching environment with considerable directivity of ions, single crystal diamond tips with different apical angles can be fabricated. Very sharp diamond tips with an apical angle of no more than about 28&#xb0; and a tip radius smaller than 50 nm are fabricated on pyramidal-shaped [001]-textured diamond films by subsequent reactive etching., The technology is based on selective etching of sp- and sp- hybridized carbons by the activated constituents of an etching environment, in particular based on atomic hydrogen, in a way similar to ion bombardment, which contributes to overall etching and local conversion of diamond to graphitic phase promoting further etching with chemically activated species. This novel method is capable of forming diamond tip arrays over large areas with great uniformity and high reproducibility. The diamond tips prepared are single diamond crystals with their [001] axes parallel each other and normal to the substrate surface. The invented technology enables the control of the apical angle, radius and density of the diamond tips.

Fabrication of single crystal diamond tips and their arrays

An organic electroluminescence device which includes an anode, a cathode, a hole transport layer, an electron transport layer, and at least one organic luminescent medium doped with a pyrazolo[3,4b]quinoxaline derivative is disclosed. The present device provides improved efficiency, and the emission band associated therewith is surprisingly narrow. The improved green emitting organic electroluminescence device exhibits high color purity.

Organic electroluminescence devices using pyrazolo[3,4b]quinoxaline derivatives

Organic electroluminescence devices are described, each of which comprises an anode, a cathode, a luminescent layer, at least one hole-transporting layer disposed between the anode and the luminescent layer, at least one electron-transporting layer disposed between the cathode and the luminescent layer, and a substrate present on either the anode or cathode. The luminescent layer in the devices uses as red-emitting materials, salicylaldiminato Schiff bases or their metal complexes based on diaminomaleonitrile and salicylaldehyde derivatives. These organic electroluminescence devices exhibit excellent color chromaticity co-ordinates and good efficiency.

Growing community of inventors

Hong Kong, China

Shuit-Tong Lee