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Semiconductor injection laser diodes emitting in the near infrared are now finding applications in optical fibre communication, consumer products such as digital discs, and optical recording. The processing techniques and properties are described here

ZnS-In phosphors, which are efficient upon excitation with λ = 3650 A , were prepared by firing in H2S at 1200°C and quick cooling to room temperature. The emission spectrum depends on the In concentration and consists of three bands at 6200 A, 5350 A and 4700 A. X-ray analysis shows that the maximum amount of In incorporated is about 10−2 gram-atoms In per mole ZnS. Refiring the phosphors at 600°C kills the luminescence at room temperature, an effect shown to be due to association. The trivalent In is compensated in the lattice by VZn. On the basis of the experimental evidence the 6200 A band is ascribed to InZn, the 5350 A band to the associate InZnVZn and the 4700 A band to VZn). ∗ The low-temperature phosphorescence of the ZnS-In phosphors is strongly stimulated by irradiation into bands at 1.8 μ and

Nematic liquid crystals are a convenient tool in the study of electrohydrodynamics. The rise time of light scattering connected with turbulent flow is found to be proportional to viscosity and inversely proportional to the square of the electric field.

Cadmium selenide TFT's operated at fixed gate and drain bias show a slow decay of the drain current. The time dependence of this decay was found to be logarithmic. Below room temperature the rate of decrease of the number of charge carriers in the surface-channel depends only weakly on both temperature and gate bias. These results can be described with a model in which tunnelling of electrons from the channel to traps in the oxide forming the gate insulation is assumed. As time proceeds the traps are filled by this process to an ever-increasing depth. Somewhat above room temperature a strong drift of a different nature occurs. In contrast to the low temperature drift, which can be suppressed by suitable treatment, this type of drift could not be removed. It presents a serious drawback to practical applications of the CdSe TFT. In several respects the TFT's used in this investigation differ from the conventional type. Their construction is briefly discussed.

The p-n-junction photovoltaic effect in Zn-doped GaP was studied as a function of various parameters. The spectral sensitivity, the temperature dependence of the short-circuit current and the open-circuit voltage are discussed. In addition to the intrinsic effect an extrinsic photovoltaic effect was found. Arguments are given to show that the extrinsic response is not an electrode effect, but is clearly correlated with the specific dope introduced into the GaP bulk.

Es werden die Fluoreszenzeigenschaften des reinen und des mit Lithium, Zink und Magnesium dotierten GaN bei Anregung mit UV-Licht und Kathodenstrahlen in Abhängigkeit der Temperatur untersucht. Mehrere Emissionsbanden wurden beobachtet, von denen die kurzwelligste Bande als Rckombinationsstrahlung freier Elektronen mit freien Löchern gedeutet wird.

A new method in making single crystals of GaP and the preparation of diodes is described. The p‐n luminescence and photoluminescence of undoped and Zn‐doped GaP are investigated and the light output of the p‐n luminescence as a function of temperature and excitation density is discussed. The spectral sensitivity of the p‐n photovoltaic effect is recorded.

In an investigation of the factors which determine the rate of electrolytic corrosion of the Al metallization in plastic-encapsulated ICs operated in a moist atmosphere, the surface conductivity of thermal SiO2 was measured as a function of relative humidity and temperature. Electrolysis in the water film adsorbed at high relative humidity produces either protection of the Al metallization by anodization or destructive corrosion at the anode and/or cathode. The occurrence of protection or destructive corrosion is mainly determined by the nature and amount of ionic impurities present in the water film and by temperature.