最新刊期
卷 2 ， 期 2 ， 1981
- 摘要：Tunnel Effect and the different behaviors of hot electrons consist of the main electronic processes under high electric field. Emphasis is made on the description of the characteristics of hot electrons, the origin and properties of electroluminescence under high electric field, the present situation in the study of electroluminescent materials and devices and also the actual problems to be solved.122|86|0更新时间：2020-08-11
- 摘要：The correlation between the Peak of spontaneous spectra and the maximum of the injected carrier distribution in the energy band, the condition of the carrier distribution-maximum situated in the bandtail; the dependence of the carrier-distribution-maximum shifting-rate with injection level on the shape of the bandtail, and on whether or not the quasi-equilibrium distribution has been reached, have been analysed theoretically both under steady and transient cases.A new method for quantitatively determining the density-of-states distribution of the tail from the steady and transient emission spectra peak shifting is proposed. An important conclusion is that quansi-Fermi level do not exist during transient spontaneous emissions from GaAs doped with amphoteric silicon. Steady and transient time-resolved spectra from GaAs homojunction and heterojunc-tion samples doped with various dopants of different concentrations and different degrees of compensation, under various injection levels at 300 and 77K, are systematically measured. The experimental results agree well with the theoretical predictions, and on this qasis, the effect of bandtailing on the transient response time of spontaneous emission Is discussed.159|68|0更新时间：2020-08-11
- 摘要：Deep level in GaxAl1-xAs LEDs are studied by thermally stimulated capacitance and relaxation capacitance.Depth, concentration and capture cross section of deep levels can be determined from experimental results.Both increase of the voltage threshold of I(Ⅴ) curve at forward bias, even with negative resistance and significant decrease of capacitance are observed with decreasing temperature. These changes can not be explained by considering shift ofF ermi level and change of permittivity with temperature. Both decrease of breakdown voltage of negative resistance and increase of capacitance were found when LEDs are illumi-neted by infrared radiation. A new main peak (1.26ev) of light emission of LEDs is observed at liquid nitrogen temperature, possibly owing to oxygen contamination.126|55|0更新时间：2020-08-11
- 摘要：The enhancement effect of cathodoluminescence and Ultra-violet excitation luminescence efficiencies of Eu3+,Sm3+ and Dy3+ in Y2O2S by codoping with a trace of Tb3+ have been investigated. The factors responsible for the enhancement are: (1)decreasing of dulk charge in the phosphors dy addition Tb3+, (2)Existing energy transfer from Tb3+ to RE3+.The experiments indicate that the sort of energy transfer is not due to a resonance energy transfer, a reabsorption of emission light and a hole transfer, but it is bue to energy transfer of free exciton into which is changed exciton bound by isoelectronic trap of Tb3+ because of thermal disturbance.153|25|0更新时间：2020-08-11
- 摘要：Residual acceptor impurities in high purity LPE-GaAs and VPE-GaAs have been investigated by photoluminescence at 4.2K and 1.8K. The experimental results show that residual acceptor impurities are C, Si, Ge in high purity LPE-3aAs and C, Zn, Si, Ge in high purity VPE-GaAs grown in AsCl3-Ga-H2 System. However, in the high purity VPE-GaAs grown in AsCl3-Ga-N2 system only carbon can be detected as a dominant acceptor impurity. The effect of some growth conditions on incorporation of residual acceptor impurities heve also been studied.117|80|0更新时间：2020-08-11
- 摘要：The liquid phase epitaxial technique which permits to grow lattice matched In1-xGaxAs1-yPy layers with reproducible composition on (100) GaAs at low temperature of 650℃. The results obtained by field emission microscopy observation, electron microscopy, X-ray double crystal diffraction, Auger electron spectroscopy and photoluminescence measurements of the epitaxial layers were given.It is shown that the epitaxial layers have flat interface of heterojunctions and good crystal quality.The relationship between lattice mismatch and interface roughness and interface width with graded composition profile of heterojunctions was also studied.144|42|0更新时间：2020-08-11
- 摘要：In this Paper the method of preparation of high efficient UV-emitting Gd and Ce-activated calcium phosphate phosphor is described. For example, CaHPO4 292.0g, CaCO3 36.0g, Gd2O3 17.5g, CeO2 30.0g and Na2CO3 flux 10.0g are well mixed and put into alumina crucible, then sintered for 2-4 hours at 1200-1400℃. Thus, Gd and Ce-activated hexagonal μ-Ca3(PO4)2 phosphor having emission peak near 350nm upon excitation with 254nm UV light is obtained. The influences of activator concentration and sintering temperature on emission intensity and spectrum are discussed.134|70|0更新时间：2020-08-11
- 摘要：The performance of maintenance is, considerably improved as a result of annealing ZnS-Cu,Eu,Br ACEL powder at a higher temperature in a shorter time. When treated the particles of phosphor must be coated with excessive copper sulphide. Otherwise, the luminescence performance would be spoilt. If excessive copper sulphide has been washed by a dilute solution of potassium cyanide (or sodium cyanide), the particles must be coated again with copper sulphide and baked, thus brightness of electroluminescence can be partially restored and the deteriorated performance improved. The reason for the improvement of the phosphor maintenance is attributed to the improvement of the condition of Cu2S phase, but not that the of luminescent center.122|51|0更新时间：2020-08-11
- 摘要：This paper deals with the thermoluminescense of ZnS-Cu, Eu, Br ACEL powder phosphor, Thermoluminescence curves of the treated and untreated phosphor are compared before and after deterioration. After electroluminescence deterioration, the area enclosed by the thermoluminescence curve was reduced while no additional emission peak could be abserved.This may be coused by ion migration which results in decrease of shallow trap concentration.In comparison with the untreated phosphor, the treated phosphor has a smaller difference between the areas enclosed by thermoluminescence curves before and after eletroluminescence deterioration.It is supposed that since the Cu2S phase and the surface condition have been improved in the process of treatment, ion migration would be suppressed, the distribution of field strength and the condition of original injected-electrons would be changed and thus deterioration improved.104|39|0更新时间：2020-08-11
- 摘要：In this paper we describe the photoluminescence properties of tetra[4.4.4-trifluoro-1-(2-thienyl)-1.3-butane-diono] europium [4-methyl pyridine] chelate and the tetra [4.4.4-trifluoro-1-(2-thienyl)-1.3-butane-diono] europium [2.4.6-trimethyl pyridine] chelate. The absorption,excitation and fluorescence spectra and quantum efficiencies of the chelates in the solid state and the solution were measured at room temperature. The effect of the solven on the luminescence properties are studied.Their luminescence mechanism are discussed the basis of the molecular structure and the luminescence properties.123|62|0更新时间：2020-08-11
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