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We have recently examined the microscopic electrical inhomogeneities present in dislocation free, floating zone, Si crystals grown under various conditions by conductivity mode scanning electron microscopy. Schottky barriers produced by evaporation of thin Au-Pd (on N type) or Ti (on P type) electrodes were employed in order to eliminate possible changes in defect structure or electrical activity during production of a diffused junction.Doped and undoped crystals, as well as crystals subjected to special treatments, such as melt quenching were examined in this study. Prior to SEM analysis, each crystal was characterized by preferential etching, Cu or Li decoration, and x-ray topography. All of the defects detected by these methods, save C impurity striations detected via their dilatation of the Si lattice in x-ray topographs, were observed in the SEM experiments. For example, “swirl” defects of both type “A” (large) and type “B” (small) were readily revealed via the enhanced recombination rate of electron beam injected carriers in their vicinity (see Figs. 1 and 2).

The formation of glassy (amorphous) metallic alloys by rapid quenching from the liquid state was discovered in 1960 (1), and subsequent work revealed that certain metallic glasses are ferromagnetic (2). Recently, transition metal based alloys, which possess Curie temperatures as high as 700°K and saturation magnetizations up to 15,000 Gauss, have been shown to be both mechanically very hard and magnetically quite soft (3). We have applied the SEM technique of Fathers et al. (4) as well as electron transmission Lorentz microscopy to a study of roller quenched (5) metallic glass ribbons of composition: TM0.75P.16X.06A1.03, where TM denotes Fe, Co, Ni, or an alloy of these and X denotes either B, C or Si (6).

Measurement of thermionic electron emission values for pointed LaB6 single‐crystal emitter cathodes has shown that 〈110〉 axial orientations yield emission values ten times higher than 〈100〉 orientations at 1545 °K. Minimum values were obtained for the 〈510〉 directions. These findings seem encouraging in achieving perhaps two orders of magnitude higher emission fluxes as compared to tungsten emitters.

We have applied the scanning electron microscopy (SEM) technique of Fathers et al. to a study of domain structure in metallic glasses of the form TM0.75P0.16X0.06Al0.03, where TM denotes Fe, Co, Ni, or an alloy of these and X denotes either B, C, or Si. The domain structure is dominated by the presence of a spatially nonuniform uniaxial anisotropy which is related to the flow processes induced by quenching the molten alloy. The existence of both a magnetostrictive and a directional ordering source of anisotropy is indicated.

The magnetic properties of zero magnetostrictive metallic glass have been investigated using both standard fluxmeter methods and domain patterns obtained from a scanning electron microscope technique. This investigation shows that the material is not magnetically isotropic but rather has preferred directions of magnetization that are determined by the details of the quenching process. The magnetic aniostropy produced by subsequent field anneal dominates the original anisotropy and determines the magnetic behavior after the heat treatment.

Pt‐Si alloy layers are formed during 130‐nsec pulsed irradiation of Pt coated Si with light from a Nd : YAG laser. The alloys form via surface melting and resolidifaction. Laser processing of arsenic of ion implanted, p‐type silicon results in formation of a p‐n+/Pt‐Si structure that exhibits rectifying electrical behavior. This structure arises because the As and Pt impurities are zone refined to different extents during resolidification of the molten surface layer.