The distribution and apparent source geometry were determined for aluminum evaporation from a 12-kW 270° electron beam gun. The distribution was measured as a function of deposition rate for rates from 1000 to 50 000 Å/min, 20 cm from the hearth. These measured distributions and those from other workers can be described not by a simple cosine relation, as has been assumed, but by a relation of the form (1-A) cosn θ+A, where θ is the angle from the vertical. The coefficient A is the normalized magnitude of an isotropic component, and n is a rate-dependent beaming exponent. The apparent source geometry was measured using a pinhole camera technique. These measurements show the evaporant to originate from the area defined by the visual beam impact point at low-to-moderate rates, and additionally from a larger virtual source at high rates or when a hearth linear is used. The run-to-run stability of the evaporant distribution was also determined.

Measurements have been made of the evaporation characteristics of aluminum, alumina, aluminum nitride, barium titanate, boron carbide, boron nitride, carbon, copper, chromium, gold, iron, inconel, lead, magnesium, magnesium fluoride, molybdenum, nickel, niobium, permalloy, sapphire, silicon, silicon monoxide, silicon dioxide, silver, tantalum, tin, tin oxide, titanium, titanium monoxide, titanium dioxide, tungsten, and zinc. Using a 6-kW, 180 ° bent-beam gun, the deposition rate, required beam power, charge material form, and suitability for evaporation were determined for each material. The evaporation rate is reported in angstroms/minute. Methods of transferring these data to other guns are developed. The beam power limit is discussed and methods of increasing the evaporation rate of power limited materials are explored. Extension of these results to other materials is discussed and examples are given.

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Large area (50cm2) thin film, band pass filters have been constructed to provide four wavelength bands for the Wide Field Camera telescope on the ROSAT satellite. The filters consist of a polycarbonate substrate coated with one of, carbon, beryllium, or aluminium, additionally a tin/aluminium filter is also available. These provide wavelength bands of mean wavelength 100, 140, 180, and 600 angstroms respectively. This paper describes manufacture, and qualification details in the context of filters launched at ambient pressure, with a very stringent requirement for opacity, at around 1800A, of better than 1O_8 of the filter area. Measures taken to protect filters against erosion by low earth orbit atomic oxygen are also briefly presented. Calibration procedures and results are discussed together with comparison of measured transmission profiles with those derived from published absorption coefficients over the range 40 to 2000 Angstrom.

The evaporation characteristics of Al2O3, As, B, Ba, BaCl2, BaF2, Be, BeO, Bi, B4C, Ca, CaF2, Cd, CdS, Co, Dy, Eu, Gd, Ge, In, Ir, KCl, KF, La, LaB6, Li, LiF, Mn, NaCl, NaF, Nd, Pd, Pt, Pr, Rh, Sc, Se, Sb, Sb2O3, Sr, S8, Ti, V, WO3, Yb, Y2O3, Zr, ZrO2 from an electron beam source are described. In addition, similar, previously published measurements of Ag, Al, Al2O3, Au, C, Cr, Fe, Inconel, Mo, Mg, MgF2, Nb, Ni, Pb, Si, SiO, SiO2, Sn, Ta, TiOx, W, and Zn have been expanded. The nonquantitative characteristics, melt type, stability, and tendency to spit, are reported, in addition to the evaporation rate, power, and pressure.