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Structural and compositional properties of hydrogenated silicon‐tin alloys have been investigated as a function of tin content, sputtering pressure, and presence of hydrogen. Transmission electron microscopy, energy dispersive x‐ray microanalysis, and scanning electron microscopy were used to detect compositional and structural inhomogeneities in these materials.

The pyroelectric effect (PE) in faulted ZnS crystals was studied experimentally in the temperature range from 100 to 300 °K. It has been found that the observed voltage pulses are due to a special pyroelectric effect which is not connected with the temperature dilation of the unit cell or any resulting change in the value of its dipole moment. The observed pyroelectric effect has been correlated with built‐in electric fields in faulted ZnS crystals. Its temperature dependence is attributed to the different magnitude of the temperature dependence of the dielectric constants in the different ZnS crystal structures.

This paper reviews applications of cathodoluminescence scanning electron microscopy in the assessment of optical and electronic properties of semiconductors. The assessment includes, for example, information on band structure and impurity levels derived from spectroscopic cathodoluminescence, analysis of dopant concentrations at a level which is in some cases several orders of magnitude better than x‐ray microanalysis, and mapping of carrier lifetimes and defects. Recent advances in both the various cathodoluminescence techniques and the processes leading to electron‐beam‐induced luminescence in semiconductors are reviewed. Possible future trends are also discussed.

Hydrogenated amorphous silicon (a‐Si:H) films were prepared by chemical vapor deposition (CVD) from mixtures of silane, disilane, trisilane, and higher polysilanes in hydrogen carrier gas at 1 atm total pressure, at substrate temperatures from 420–530 °C. Experimental parameters are explained and properties as a function of these parameters are shown. The measurements include hydrogen content (by IR), optical, electrical, and photovoltaic properties of the material. In most respects, the CVD material closely resembles the a‐Si:H usually prepared by glow discharge. The following differences have been noted: (1) the CVD a‐Si:H shows no IR absorption at 840–850 cm−1, which is consistent with the expected better thermal stability of the CVD material because of the much higher substrate temperatures in the CVD process than in the glow discharge process. (2) The band gap of CVD a‐Si:H is lower by about 0.1 eV than glow discharge a‐Si:H of the same hydrogen content. Thus, the band gap of CVD a‐Si:H is better mat...

Electroabsorption (EA) measurements on ZnS crystals were performed. The electric fields were applied parallel to the polar c‐axis. In single‐crystal regions the EA was found to be independent of the sense of the electric field. On the other hand, in those crystals which contain various polytypes and stacking faults and exhibit an anomalous photovoltaic effect the EA was strongly dependent on the sense of the electric field with respect to the crystallographic polarity. From the spectral and field dependencies of the EA it was concluded that there exist in these crystals internal fields which are uniquely related to the crystallographic polarity. The sense of the electric fields in the various structures was determined. The strength of the fields was found to depend on the structure composition of the crystals; fields up to 105 V/cm were estimated. The existence of opposing internal fields, as found in this work, verifies the assumption of several authors in explaining the anomalous photovoltaic effect in ZnS crystals.

Decay of the electron‐beam‐induced current in hydrogenated amorphous silicon devices at continuous electron irradiation is investigated as a function of both the electron‐beam energy and current. The decay mechanism is based on the formation of electron‐irradiation‐induced microscopic defects that act as recombination centers and reduce the lifetime of carriers.

Epitaxial InAs/GaAs, GaAs/Ge/Si, GaAs/InP, and InAs/InP heterostructures are grown by molecular‐beam epitaxy. Transmission electron microscopy studies reveal that, for these heteroepitaxial systems, the threading dislocation density is inversely proportional to the epilayer thickness. At a given thickness, the threading dislocation density is relatively insensitive to lattice mismatch (3.2%

The electron‐beam‐induced current (EBIC) mode of a scanning electron microscope is used to investigate the effect of hydrogen passivation on silicon grain boundaries. A reduction in the grain boundary surface recombination velocity is observed by EBIC linescans after passivation. The EBIC signal decays with repeated linescans across hydrogen‐passivated grain boundaries. This is probably associated with the electron‐beam‐induced breaking of passivated bonds in the grain boundary. Subsequent annealing at about 200 °C restores the hydrogen passivation effect on grain boundaries.

The reaction between evaporated amorphous silicon films and chromium layers was studied using transmission electron microscopy and both transmission electron diffraction and reflection electron diffraction. When a‐Si and Cr films were deposited in the same pumpdown, the formation of CrSi2 was observed at temperatures as low as 400 °C. No reaction was observed when a‐Si was deposited on electrodeposited Cr.