| 摘要 |
<PICT:1031963/C6-C7/1> Substrates, particularly vertical glass sheets or dropped particulate substrates, are vacuum coated by rotating a crucible 13 having an open end axially thereof and containing molten material, such as in a ring 26 held against the inner surface e.g. groove 22 of the crucible by centrifugal force, evacuating the space external of the open end, e.g. in a vacuum chamber 11, heating the molten material, preferably by directing an electron beam 24 from a generator 25 through the open end upon the surface thereof, to vaporize material therefrom, and positioning a substrate 27 in front of the open end for receiving deposition of vapour emitted axially. The vapour may be focused with hot reflecting surfaces 17 into a directed stream, the direction of which may be changed by tilting the drive shaft 19 of the crucible within vacuum seal 20 e.g. by altering position of drive motor 18. Material such as wire 21 may be fed into the crucible e.g. through vacuum lock 23 to maintain a reservoir of molten material. A pool of material of high boiling point may be first formed, e.g. of Zr, Nb, Ta, Hf, U, W or Mo, or nitride of Al or B, or boride of Hf, Zr, Ti or Ta, then additional material, such as Al, having a lower boiling point, may be fed into the pool e.g. as wire, rod 21, small pieces or air-driven powder to be instantly vaporized. Rapid hangover may be effected from one additional material to another, e.g. from Al to Ag. For alloy coatings, a plurability of wires or rods may be fed into the pool which is maintained at a temperature above the boiling points of the alloying constituents; an example of Nb-Sn alloy is given. Two opposed horizontal crucibles may be used in the vacuum chamber for coating both sides of a substrate such as continuously moving thin sheet (see Fig. 6, not shown). The crucible may be rotated about a vertical axis with open end up (see Fig. 8, not shown) at a rate sufficient to depress the centre of the surface of molten material so that vapour travels axially from the open end. |
