摘要 |
<p>Apparatus for the physical vapour deposition of an alloy whose constituent elements have widely differing vapour pressures comprises an inner evaporation crucible (1) surrounded by a second evaporation crucible (2) having an array of nozzles (9) angled towards collector (5). In use of the apparatus, a charge (3) of relatively low volatility is evaporated from inner crucible (1) using an electron beam (7) focussed by magnet (8). Charge (4) in second crucible (2) is of much higher volatility and is evaporated by radiant heating. The nozzles (9) direct the vapour from charge (4) along pathways which intersect the vapour rising from charge (3) such that the combined vapour stream reaching collector (5) is an intimate mixture of constituents. The nozzles (9) may also serve to control the flow rate of vapour from the second crucible (2).</p> |