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Thin Pt, Pd and Ni films have been reacted with single crystal Si, using Q‐switched Nd:YAG laser pulses of 100 nsec duration in the power range 18–50 MW cm−2, to produce layers that are laterally very uniform in thickness but are not single phase. Average composition and thickness of the reaction product layer can be changed over a wide range by varying starting film thickness and laser power. The microstructure of the reacted layers indicates that reaction occurs via surface melting, mixing and rapid resolidification. Molybdenum and Nb films have been reacted with Si at powers of approximately 90 WM cm−2.

We have grown high quality epitaxial Si films from amorphous deposited layers using pulsed and CW Nd:YAG lasers. Pulsed irradiation produced epitaxial growth by melting and resolidification. The regrowth is relatively insensitive to interfacial and incorporated impurities of C, O, and Ar. Gallium dopants in the amorhous film redistribute within the melt and are zone refined towards the surface during solidification. Gallium left within the regrown layer exceeds the maximum equilibrium solid solubility by an order of magnitude. Continuous wave irradiation can produce epitaxial regrowth in the solid phase providing that the silicon is deposited on an atomically clean substrate. No Ge dopant redistributed has been observed in this regime.

Silicon crystals that have been annealed by both Cw and pulsed laser irradiation have been examined by scanning, charge collection microscopy. In this technique, the short circuit current across a laser annealed diode is employed as the video signal in a scanning electron microscope, which provides a source of focused carrier injection. Repetitively pulsed, overlapping spot arrays show excellent uniformity on a scale large compared to the laser spot size, but exhibit inhomogeneity in the 1 to 10 μm range. Specifically, 1 μm ripple is observed in diodes annealed at laser powers near the surface melting of the sample surface. In well‐annealed material, the periphery of each laser spot is the region of best charge collection. Measurement of collection efficiency vs. injection depth yields estimates of carrier lifetime in the laser melted an resolidified layer. These are always small, of order 1 nsec. Finally, we have observed conversion of p‐type silicon surfaces to n‐type following CW laser annealing.

A year ago C. D. Graham Jr. [1] reviewed the behavior and applications of ferromagnetic glasses. This paper will discuss the progress made since that time by a number of investigators in various laboratories. Substantial effort has been directed towards the study of the dynamic properties of these alloys. The dynamic properties examined include the complex permeability and the coercive force as a function of frequency, the rapid flux reversal time as a function of applied field, and the damping associated with domain wall motion. Essentially all of the dynamic properties can be understood by considering the ferromagnetic glasses to be just soft magnetic materials with a resistivity about three times that of permalloy. The details of the domain structure in the two materials differ, but not in a substantial or fundamental way. Because the glassy alloys are in general not isotropic, their domain structure in determined by a local anisotropy which arises due to strain or ’’pair ordering’’.

Metallic glasses undergo structural relaxation at elevated temperatures and their mechanical properties are often dramatically altered as a consequence. We have discovered that the magnetization behavior of a (Ni.5Co.5).75P.16B.06Al.03 glass is similarly sensitive to heat treatment. The ferromagnetic transition in this material is not sharp, and heat treatment serves to broaden the transition further. Tc cannot be defined by conventional methods; e.g., (M)1/β vs (H/M)1/γ plots or a.c. permeability measurements. Both the initial permeability and the high field magnetization increase upon annealing, at rates that are indentical to those of structural relaxation processes. While transmission electron microscopy examination of the glass failed to reveal either crystallization or phase separation, the magnetic properties suggest that a microscopically inhomogeneous distribution of the ferromagnetic species is developed during quenching and heat treatment.

Magnetic properties of metallic glasses in the system (Fe‐Co‐Ni) 0.75 (P‐B‐Al)0.25 have been investigated. Samples were made by the roller quenching technique in the form of ribbons 0.002 in. thick and about 0.125 in. wide. Room temperature saturation magnetization, 4πMs, ranged from a high value of 13,500 Gauss for Fe0.75P0.06Al0.03 to essentially zero for Ni0.75P0.16B0.06Al0.03 which exhibits only weak temperature independent paramagnetism. The highest Curie temperatures occurred in mixed Fe‐Co alloys with a high value of 715°K for (Fe0.4Co0.6)0.75 P0.16B0.06Al0.03. The sign of the magnetostriction was found to change from positive for Fe rich alloys to negative for Co rich alloys so that low or zero magnetostriction composition can be made near the Co rich side of the pseudo‐ternary phase field. For example (Fe0.04Co0.96)0.75P0.16B0.06 Al0.03 has nearly zero magnetostriction. This alloy responds to heat treatment in a magnetic field, developing properties which compare favorably with commercial superma...

Magnetic properties of centrifugal spin quenched ribbons of metallic glasses in the system Fe‐Mn‐P‐B‐Al were studied from room temperature to 1.5°K, with applied fields up to 15.3 kOe. The magnetization vs. temperature curve for (Fe.5Mn.5) .75P.16B.06Al.03 has a broad maximum near 20°K, observed after cooling in zero applied field. Cooling from higher temperatures in the presence of 15.3 kOe applied field, essentially eliminated the broad maximum and established an asymmetrical displaced hysteresis loop at 1.5°K. The intrinsic coercive force was nearly zero on one side, and 7200 oersteds on the other, while the remanence was zero on one side and 3.5 e.m.u./g on the other. Magnetically cycling the field cooled sample several times with ±15.3 kOe at 1.5°K changed the magnetic state of the specimen, resulting in a nearly symmetrical hysteresis loop, with lower coercivity and remanence. Cooling in zero field established a symmetrical hysteresis loop with lower coercivity of ±1600 Oe. Magnetic saturation was n...