最新刊期
卷 5 ， 期 3 ， 1984
- 摘要：We have studied the h.minescerce kinetties of bourd exciters in nitrgen doped Ⅲ-Ⅴ binary or trinary compounds, considering various radiative and nonradiative processes.Ⅲ-Ⅴ compounds are excited by the light of above-gap energy. The free exciton is first created,then trapped by N impurities,ard after that the bound exciton can be either annihilated radiatively ard nonradiatively cr dissociated, as a result of thermalization, from the impurity to become a free exciton. A part of these free excitons will be trapped again by other centers ard the excitation energy is transferee to the other eeriers. The clrei rart cf them will be directly annihilated through radiative cr ncriadiative transitions.123|61|0更新时间：2020-08-11
- 摘要：The paper reports the results of laser selective excitation cf a trivalent rare earth ion in semiconducting compound for the first time. The samples are ZnS:Er3+ sintered slices.In laser selective excitation experiments, NRG-FTL-2000 dye laser pumped by a nitrogen laser was used. The emission was analysed by Spex 1403 double grating spectrometer. Then the signals were measured by photon counting system or PAR 162/165 boxcar.110|49|0更新时间：2020-08-11
- 摘要：Effect of deep level on luminous efficiency of Ga1-xAlxAs is studied by DLTS method. The concentration, the depth and the capture cross-section of deep levels are measured for three LEDs with different efficiencies, and then the life time τn of majority carrier in n region are calculated. The emission spectra and the luminous flux of these LEDs are also measured.111|31|0更新时间：2020-08-11
- 摘要：The bard offset cccuring at abrupt heterc-interface in heterojunction devices has been studied for many years. It has been demonstrated that by present developing technology,the fabrication of true abrupt or grede heterojunction seems not difficult. Particalarly,in the GaAs/AlGaAs system, MBE and MOCVD are available to grow for this purpose. However,relatively little research has been carried on the optical properties of hetero-interface of such layers. The spikes and notches in the discontinuous energy bard at the hetro-interface has never been observed directly.The purpose of this paper is to report a new PL phenomenon in LPE GaAs/AlGaAs heterojunction devices with grade quantum confinement.Special light doped and urdoped GaAs/AIGeAs fairples with different thickness are grown in general LPE system. Care is taken during the growth to pull the LPE system slider from the boat factly, and the clearances are small(~25nm)in order to have the interface as abrupt as possible. Selective and controllable chemical etch are used to make a set of step-etch samples with different layer thickness apart from heterc-interface for PL experiement. Liquid He cryostat,Ar laser,the 1M spectrometer,cooled,(77K) photomultiplier tube,quantum photometer and recorder are equiped for the PL measurmenl (Fig.l). The intensity of laser power and the temperature of the samples can be changed in a large scale dependent on the experiement.98|71|0更新时间：2020-08-11
- 摘要：In this paper, the distribution and the origin of the luminescence region in DCEL panels (sandwich cells) have been investigated. The experiments are carried out by observing the cross-section of the panels in microscopy. It is found that the luminescence region in DCEL devices (sandwich cell) can be located anywhere, for example, at the region close to anode or cathode, or in the middle of phosphor/binder layer. It is suggested that the distribution of luminescence region of DCEL panels is random.The position of luminescence region depends mainly on the way of forming process and is also related to the structure defects in the phosphor/binder layer, the properties of phosphor and the electrode materials etc.98|140|0更新时间：2020-08-11
- 摘要：The results of preparing ZnxCd1-xSySe1-y;Gu,Br yellow ACEL powder have been reported. In zinc sulphide, the bottom of conduction band lowers down if Cd2+ are substituted for Zn2+, the top of valence band arises if Se2- are substituted for S2-. Such substitutions can change the band gap Eg of ZnS. (1) Se2- are substituted for S2- partly in ZnS, i.e. Zn (S,Se). Yellow ACEL Zn(S,Se):Cu, Br can be obtained when the proportion of Se is more than 50%. But in this case, the ACEL luminance decreases significantly. It is difficult to make practical display devices from them. (2) Cd2+ are substituted for Zn2+ partly in ZnS, i.e.(Zn,Cd)S. If one wants to shift ACEL spectrum of ZnS:Cu to the red by a certain amount, the fraction of Cd necessary to be added to ZnS is less than that of Se. But X-ray analysis of ZnxCd1-xSySe1-y:Cu, Br shows that aaaaaaaaaaa phase appears in the mixed crystals when x<0.94. Therefore, its ACEL luminance also decreases. It is reasonable to assume that if both Cd2+ and Se2-are added in small amount, the EL spectrum can be shifted to the yellow region without remarkably decreasing the EL intensity.109|27|0更新时间：2020-08-11
- 摘要：In this paper a convenient method of the preparation has been given for green-emitting phosphor Zn2GeO4·GeO2:Mn2+, which has high luminance, white body colour and even size. By adding excess GeO2 in the raw material the preparation temperature is lowered, the reaction process is accelerated and the luminance is enhanced.The optimum conditions for the preparation of the sample were summarized in Table 2 and a comparison of its luminarce with certain green phosphors was made(Table 3). Table 3 shows that photolumirarce of this phosphor is higher than that of Zn2SiO4: Mn2+ and (Ce,Tb)MAl11O19.102|38|0更新时间：2020-08-11
- 摘要：Zn diffusion in Ga1-xAlxAs and GaAs was studied in the temperature range from 720℃ to 750℃. The relation of the junction depth (xi) with the time (t) and the temperature (T) of diffusion has been investigated. The variation of junction depth (xi) with aluminium composition was also investigated. ZnAs2 dissociates during the reaction ZnAs2⇔1/3Zn3As2+1/3As4. The amounts of ZnAs2 was about lmg/cm3 each time.Fig.3 shows that at T=740℃ the junction depth (Xj) varies with the square root of the diffusion time for Zn diffusion in Ga1-xAlxAS,GaAs and GaAs1-xP.89|23|0更新时间：2020-08-11
- 摘要：GaP was grown by metal-organic vapour phase epitaxy (MOVPE) technique under different phosphorous pressure. The deep levels produced under different growth conditions were investigated and the natvres of the deep levels were recognized by the aid of combination of luminescence and jurction techniques.During the MOVPE growth process, the Ga flow was kept unchanged between different runs to ensure a constant growth rate (0.1μm/min), but the P mole fraction (mf) varied for different runs ranging from 0.97 to 6.2×10-3 mf to form different nonstoichiometry. The grown layers had carrier concentrations of 0.9-6×1016cm-3 as deduced from C-V measurements on Cr evaporated Schottky barriers. p+n diodes were produced by Zn diffusion.110|52|0更新时间：2020-08-11
- 摘要：This paper presents the method of box diffusion with fixed pressure using ZnP2 as a diffusion source to get high surface concentration in the LPE layer of GaP. It is econmic and technologically simple as comparing with the ordinary closed tube diffusion method. The quartz box with a polished cover was designed, which enables the Zn, P4 vapor to diffuse into GaP surface layer at 810℃. The movements of the Zn vapor atoms and P4 vapor molecules were analysed, the relation between the escape rate of the Zn atoms (or P4 molecules) and the box capacity,the structure factor of the gap was calculated.The formula (9) is the theoretical expression of escape rate of the Zn atoms through the gap between the cover and the box, where D is diffusion coefficient, V is the effective volume of the box, L,Δ,l, is parameters of the gap. We define G=LΔ/l where G represents the structure factor of the gap. Then, the expression of escape rate is:dN/dt=-GDN(t)/V.98|46|0更新时间：2020-08-11
- 摘要：We often need to analyse a series of experimental data. A method frequently used is to fit the experimental data with a theoretical formula by adjusting the values of parameters in this formula.We have developped a programme to find the best adjusted values of the parameters with which a minimum deviation between the experimental data and the calculated values should be given.This programme allows to input the data by using either keyboard or on-line. Various functions can be easily chosen in this programme for different purposes.A complex spectrum can be deconvoluted into several sub-bands by using this programme.There are two modes to-fit the experimental data:manually fitting mode and the automatically fitting mode. In the former,the user can choise the test values of the adjustable parameters throuwh the keytcard. The experimental data and calculated curves shall be shown on the CRT screen.Some additional features are designed in this program me, such as the print of the best adjusted values of parameters, the plot of the experimental data and calculated curves.Two examples are given in this paper in order to explain the usage of the programme.118|69|0更新时间：2020-08-11
- 摘要：Electroluminescence devices of trivalent rare earth ions(RE3+) and divalent manganese ions reported so far are high field electroluminescence devices with the excitation mechanism of impact excitation[1,2]. We have studied the excitation spectra of ZnS:RE3+ around the band gap and recognized the possibility to design devices with forward biased electroluminescence of RE3+. The necessary requirement is the injection of both electrons and holes into the region where RE3+ ions are present. Such electroluminescence has been observed in Er3+ implanted ZnS:Er3+ diode. The observed electroluminescence has been experimentally proven to be forward biased injection electroluminescence, not by impact excitation.The electroluminescence spectra of ZnS:Er3+ diode in the forward bias and the reverse bias are the characteristic spectra of Er3+. The ratios of the intensities of the 18800cm-1 (the transition of 4S3/2 to 4I15/2) emission lines to that of the 18050cm-1 (the transition of 4F9/2 to 4I15/2) emission lines were measured. The ratios aaaaaaaaaaa in the reverse bias are found to increase with the reverse bias(Fig.1(a)),which is direct evidence of impact excitation according to Krupka’s analyses [4]. In contrast, the ratios a in the forward bias are found to be a constant at different forward bias (Fig.1(b)), which shows that the electroluminescence of Er3+ in the forward biased ZnS:Er3+ diode is the forward biased injection electroluminescence, not by impact excitation. Electrons injected from the In contact and holes tunneled from the Au contact give energy to Er3+ ions through certain mechanisms, Er3+ ions are excited and then give luminescence.Since the efficiency of electroluminescence by impact excitation are not high [2,5], the present work gives new clues to raise the efficiency and the brightness of RE3+ electroluminescence.Optimized structures of devices will reduce operating voltage and raise efficiency of the forward biased injection electroluminescence of RE3+.97|37|0更新时间：2020-08-11
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