Papers by Keyword: ZnSe

Abstract: With the development of high power laser systems, laser protection of optical components becomes more and more important. In order to enhance the laser-induced damage capability of optical films components, besides advanced methods and processes, post-treatment has significant influence on the laser-induced damage threshold (LIDT) of thin films. Q switch Nd:YAG laser of the working wave length at 1064nm, was used to post process on ZnSe single layer films with thickness of /2 (=1064nm) deposited by thermal evaporation, and the laser-induced damage and optical properties were investigated. By changing the energy density and pulse number under the spot size remained a fixed value, their effects on thin films damage threshold were studied respectively, the optimal processing parameters were obtained: energy density is 3.0 J/cm2 and pulse number is 1.The LIDT of post processed ZnSe films was improved from 5.0J/cm2 to 8.2J/cm2.

Abstract: ZnSe is important Ⅱ-Ⅵ semiconductor luminescence materials, and it is the structure of sphalerite and is the face-centered cubic crystal. W/O microemulsion method has the peculiarity of tester simpleness, easy manipulation, room temperature react etc. In this paper ZnSe nanometer line was synthesized in CTAB/cyclohexane/isobutanol/water quatemary microemulsion system. The morphology of the final products were characterized by transmission electron microscopy. according to the means, this paper researches the effect of aging time and the reactant contentration to nanometer materials. The result is that the nanometer line can be obtained through the different reactant concentration and the aging time under certain conditions. Finally, according to TEM chart, this paper infers the formation mechanism of the ZnSe.

Abstract: Crystalline thin of zinc selenide have been electrochemically deposited on conducting substrates of indium tin oxide, ITO glass. Initial investigation with voltammetry was done and shows that the zinc selenide films were stable towards oxidation. The best deposition potential obtained was at -0.95 V vs. Ag /AgCl while at lower deposition potentials, the films do not form well. Energy Dispersive Analysis and X-Ray spectrum indicate that the films deposited at 65oC and -0.95 V vs. Ag/AgCl have nearly stoichiometric Zn: Se ratio.

Abstract: There were carried on experiment in zinc sulfate and selenite sodium electrolyte solution. To further studying the influence of the ZnSe films ingredient and the appearance influence of electrochemical formation ZnSe thin films, the deposition parameters, which are the pH, Zn²⁺/SeO₃^2- molar ratio, complexing agent sodium citrate, bath temperature and current density, are studied by the orthogonal experiment, the influence on Zn of the parameters from strong to weak are attained.

Abstract: A model to explain forward bias capacitance-voltage measurements is presented and compared with experimental results. Forward bias capacitance-voltage measurements, with environment light, were performed in a sample containing CdSe ultra thin quantum wells periodically embedded on undoped epitaxially grown ZnSe on a semi-insulating GaAs(001) substrate. A Au Schottky contact and annealed Ti/Pt/Au ohmic contacts were deposited on the sample surface in a coplanar cylindrical geometry. Under this model both type of carriers are necessary to explain the capacitive (holes) and resistive (electrons) behaviors. The measurements are fitted following the presented model, reasonable agreement is obtained. The quality factor Q is calculated and it is found to be smaller than one, hence no correction is needed. The charge carrier density profile is done on the capacitance voltage measurement. The experiments indicate a periodic charge distribution in the samples attributed to charge captured in the ultra thin quantum wells.

Abstract: The ZnSe thin films are co-deposited in the ZnSO4, Na2SeO3 and sodium citrate acidic solution, and the mechanism of the ultrasonic and pulse electrodeposition for ZnSe films is explained by the electrode-solution interface action model. Ultrasonic increases the activation energy of the [ZnCit]- and HSeO3 - and improves flow field of the solution between electrode and solution interface. The pulse current promotes the diffusion of solution and advantageously realizes the co-deposition of ZnSe films. The ZnSe thin films are pulse electrodeposited in zinc sulfate, selenite sodium and sodium citrate acidic solution with the action of ultrasonic. Finally, the ZnSe films have been characterized by the scanning electron microscope (SEM), the energy dispersion analysis of X-ray (EDAX) and X-ray diffraction (XRD).

Abstract: The principle, of which the ZnSe thin films are co-deposited in the ZnSO4 and Na2SeO3 acidic solution by electrochemistry, is explained by the electrode-solution interface action model. The current density and the duty cycle of the pulse current promote the diffusion of solution and affect the co-deposition of the ZnSe films. The ZnSe thin films are pulse electrodeposited in zinc sulfate, selenite sodium and sodium citrate acidic solution. The sodium citrate, which is one kind of complex agent, simultaneous also one kind of buffer agent and has certain buffer action, would affect the quality of the ZnSe films. Finally, the ZnSe films have been characterized by the scanning electron microscope (SEM) and the energy dispersion analysis of X-ray (EDAX).

Abstract: II-VI inorganic/organic heterostructures consisting of ZnSe and tris(8-hydroxyquinoline) aluminum (Alq3) were prepared by electron beam evaporator. Alq3 layer with 20 nm was grown between 200-nm ZnSe layers. Photoluminescence measurement was conducted at various temperatures in order to investigate the important temperature-dependent parameters of this structure. PL spectra revealed thermal population of exciton state and the change in PL quantum efficiency of the film.

Abstract: In this paper, particular CVD processes of so-called Se method with solid substances as starting materials was investigated to fabricate ZnSe. On the basis of detailed experimental researches, the growth model and dominant regime of deposition rate were discussed. ZnSe of high optical properties was produced under optimized process conditions. The grain size of CVD ZnSe by Se method is less than 10μm, and its average transmittance in the wavelength range of 0.55~20μm is up to 70%.

Abstract: ZnS and ZnSe for infrared optical windows were fabricated by particular Chemical Vapor Deposition (CVD) process with so-called S method and Se method respectively. Their morphology and defects are reported in this paper. The microstructure, composition and the influence on optical properties of the defects were investigated. The process reasons leading to these defects were discussed as well. Hot isostatic pressing (HIP) treatment was adopted to eliminate some of the defects, and the effect of HIP on optical properties was evaluated.