Valved Corrosive Cracker Source for Sb, Te, Mg

Controlled Injection of Radicals of Sb, Te, Mg or other Corrosive Materials

At a glance

  • Evaporation and cracking of Sb, Te, Mg and other corrosive materials
  • Large crucible capacity of 420 cm3
  • Fast, stable and reproducible flux control
  • All PBN construction of valve and cracker stage
  • Easy installation and refilling procedure

The Valved Corrosive Material Cracker Source is designed for controlled injection of radicals of antimony, tellurium, magnesium or other corrosive materials in standard MBE applications. Parts directly exposed to the evaporant like the crucible, the valve mechanism, the injector tube and the cracker are solely made from PBN in order to minimize corrosion of the cell.

A mixture of larger molecules is produced by sublimation of the evaporant within the reservoir. The resulting beam flux is controlled by an all PBN mechanical valve unit and finally the gaseous molecules are dissociated within the thermal cracker stage to form a well-defined molecular beam, e.g. of Sb2 species.

The source consists of the 420 cm³ reservoir, built into a water-cooled vacuum enclosure that also houses the valve unit, and the injector tube with a thermal cracker unit on top.
Operation of the mechanical valve unit shows fast, stable and reproducible flux control. Together with the valve controller an easy handling and integration into the MBE system is provided.

Three independent heater circuits allow precise and flexible adjustment of the temperatures in each part of the cell in order to provide sufficient material vapor and avoid condensation within the valve or injector tube and to ensure maximum cracking efficiency, each according to the requirements of the particular evaporant.

The special design enables easy and safe refilling of the crucible from the backside of the cell without the need of removing the complete cell from the system.