City University of Hong Kong

Nano and Advanced Materials Institute Limited

Shuit Tong Lee

Chun Sing Lee

Yat Wah Lam

Peng-Fei Wang

Baoxiu Mi

Zhangda Lin

Hin Koon Woo

Bello Igor

Caijun Zheng

Xiao Hong Zhang

Dorothy Duoduo Ma

Man Keung Fung

The present invention provides a bipolar compound represented by formula (I) and the derivatives thereof as a host material having excellent bipolar transporting properties for organic light-emitting diodes (OLEDs). The present invention also relates to a device including at least a layer of the bipolar compound and/or the derivatives thereof as a host material and a method of making the same. 

Bipolar compound as a host material for organic light emitting diodes

A luminescent system includes a layer of donor material, an acceptor material and a barrier layer therebetween. The energy transfer between the donor and acceptor is biased to the acceptor layer, by an asymmetric energy transfer efficiency created by the barrier layer. Energy from the donor material is converted into photo-luminescence in the acceptor layer by discouraging photo-luminescence quenching caused by energy backflow.

Luminescent system

This invention relates to an organic electroluminescence (EL) device and to the use of a tris-cyclometalated iridium complex with a 3-Phenyl-azine ligand for thin-film type organic electroluminescence devices. The iridium complexes used have the following formulae: 

Red-emitting electrophosphorescent devices

A method for the growth of diamond on a substrate combines an ECR (Electron cyclotron resonance) MPCVD (Microwave plasma chemical vapor deposition) method with a MPCVD method in one system. A two-step diamond growing method comprises firstly etching and nucleation performed by the ECR method and then diamond grown by the microwave plasma CVD method. Not only are high quality continuous polycrystalline diamond films on silicon wafer obtained but also heteroepitaxial growth has been achieved in the present invention. Auger electron spectroscopy (AES), scanning electron microscopy (SEM) and Raman spectroscopy have been used to characterize the structure and morphology of the synthesized diamond films.

Deposition method for heteroepitaxial diamond

A method and an apparatus have been developed to deposit heteroepitaxial beta-silicon carbide films on silicon using bias-assisted hot filament chemical vapor deposition (BA-HFCVD). The apparatus includes a graphite plate as the carbon source and the silicon substrate as the silicon source. Hydrogen was the only feeding gas to the system.

Growing community of inventors

Hong Kong, China

Shuit Tong Lee