%0 Journal Article
%T The Spectrum of Quantum Dots Film for UV CCD
%A Lin Jiang
%A Haojie Sun
%A Bang-lian Xu
%A Da-wei Zhang
%A Chun-xian Tao
%A Yuan-shen Huang
%A Zheng-ji Ni
%A Song-lin Zhuang
%J Journal of Spectroscopy
%D 2013
%R 10.1155/2013/803907
%X A new kind of UV-responsive film with quantum dots (QDs) fabricated by a spin-coating method is proposed in this paper. In a previous study, the monolayer QDs film is deposited onto fused silica slides by the spin-coating way, which has some luminous problem. The introduction of composite QDs coating which adds PEDOT:PSS and poly-TPD films to the monolayer QDs film is found to have excellent performance. The reason can be that PEDOT:PSS and poly-TPD weaken the scattering and enhance the emitting of quantum dot fluorescence. The intensity of photoluminescence (PL) for composite QDs coating is dozens of times stronger than that for monolayer QDs film. Experiment results show that this composite coating has excellent fluorescent properties and emits a blue purple glow together a wide excitation spectrum field from 190£¿nm to 300£¿nm. The spectrum of the composite coating matches accurately with the detected zone of CCD, which achieves an outstanding UV-responsive coating for conventional silicon-based image sensors. 1. Introduction Silicon-based imaging detector CCD has been widely used in the scientific fields. But the typical CCD image sensors are not sensitive to ultraviolet (UV) radiation, because the penetration depth of UV photons can only reach about 2£¿nm in a polysilicon gate material with thickness of 1£¿¦Ìm [1]. Therefore researchers from all over the world have quested the method of enhancing the UV response of the CCD. In order to enhance the UV response of CCD detectors, a kind of UV-responsive film has been coated on the surface of CCD, which could absorb the UV radiation and reemit it in the visible spectrum where photons can penetrate the gate material. This method is very useful since it does not require change the structure of the typical CCD to be changed, and the production engineering will be simplified [2]. The research was started in the UV-responsive film abroad since 1980s. According to the used materials, the conversion film can be divided into two categories¡ªorganic film and inorganic one. Organic conversion coating technology is relatively mature, with various products invented. However, this kind of film has a fatal weakness that the degradation of organic molecules in the UV radiation is very fast. In the light of illumination for 1£¿¦ÌW/cm2, the organic molecules degrade exponentially with the rate highly up to 3% [3¨C5]. Moreover, because of the organic nature of organic molecules and their low melting and boiling points, stability of these films has also been in question. Inorganic fluorescent material is usually composed by rare
%U http://www.hindawi.com/journals/jspec/2013/803907/