Vaporizer cell used in a molecular beam epitaxial process comprises a crucible having a heater and an opening, and a covering unit formed by a plate-like screen

摘要

Vaporizer cell (10) comprises a crucible (11) having a heater (12) and an opening (13); and a covering unit formed by a plate-like screen (14) having a lateral dimension which is smaller than the diameter of the crucible opening and arranged in or at a distance from the opening. An Independent claim is also included for a process for forming a vaporized layer on a substrate using the above cell. Preferred Features: The covering screen has a second heater (15) and an adjusting unit (20) by which the screen can be distanced from the crucible opening. A nozzle plate is arranged on the crucible opening or on the crucible collar for forming a vapor stream.