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Vapor‐deposited amorphous silicon films of 4000 A thickness have been epitaxially crystallized on (100) silicon substrates by pulsed Nd : YAG laser radiation of 125‐nsec duration at power levels of 90–120 MW/cm2. The epitaxial layers were found to be defect free when examined by transmission electron microscopy and Rutherford backscattering. Patterned arrays of epitaxial crystal were produced by overlapping individual 39‐μm laser pulse spots.

Polycrystalline silicon films on SiO2 and Si3N4 may be processed by tightly focused, overlapping laser pulses to yield large‐grained (1–5μm) material. In individual nonoverlapping spots the large grains are arranged in concentric rings whose origin is clarified in this letter.

Extensive seeded epitaxial growth of crystalline Si over SiO2 was achieved by an oscillatory regrowth method applied to rectangular Si pads recessed into a thick SiO2 film. Narrow (≃5 μm) via holes linked the pads with the bulk (100) Si substrate. Oriented single crystals propagated as far as 500 μm from the seeding area, following the long term advance of a scanned focused laser beam.

We have reacted thin Pt, Pd, and Ni films with single‐crystal Si using Q‐switched Nd : YAG laser pulses of 100‐nsec duration in the power range 18–50 MW cm−2. The layers are laterally very uniform in thickness but are not single phase. Average composition of the reaction product layer can be changed over a wide range by varying film thickness and laser power. The microstructure of the reacted layers indicates that reaction occurs via surface melting, mixing, and rapid resolidification.

Contrast from domain walls in materials with cubic magnetic anisotropy has been observed in scanning electron microscope (SEM) images. This contrast, which is visible in both the backscattered and absorbed current images, with normal electron beam incidence arises from the interaction of the convergent incident electron beam with the domains on either side of the wall.

Laser melting of crystalline silicon introduces electrically active defects which are observed by capacitance transient spectroscopy. The electrical activity of these point defects is neutralized by reaction with atomic hydrogen at 200 °C.

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.