Get a cost-effective solution that's ideal for your high-volume, high-value MBE process needs with reliable Veeco Single Filament Sources. They feature dependable band thermocouples and single heater filaments for 750-1200°C operation. Three system configurations, and many crucible sizes, are available. All offer stable and consistent fluxes of high vapor pressure materials.
- Patented design with more than 1125 in the field
- Single filament “cold-lip” and “hot-lip” designs
- Compatible with virtually all power supplies
- Wide range of sizes available
- Excellent performance and value
Veeco MBE Single Filament Sources are available in three versions:
- Standard Filament Source. The Standard Filament Source is a general purpose source featuring a single uniformly distributed heater filament. All designs include a band thermocouple with a large crucible contact area. Although source heating is uniform, the source is slightly cooler at the tip due to radiative heat loss at the crucible orifice, especially for the larger capacity sources. For evaporation of aluminum, it may be desirable to enhance this “cold-lip” effect as discussed below.
- Modified Filament Source. This source features a patented “modified” single filament design. “Hot-lip” heating is achieved with one filament which uniformly heats the bottom portion of the crucible but includes extra filament density at the top to compensate for radiative heat loss at the orifice. This design is particularly effective with smaller capacity crucibles.
- Cold-Lip Source for Aluminum. Molten aluminum wets PBN, often resulting in charge creep and overflow in conventional sources. Factors contributing to aluminum overflow include source installation angle, amount of aluminum loaded, and source ramp rates. Users observing persistent creep and overflow problems with standard sources may require a special single filament source with a shorter filament that produces an exaggerated “cold lip.” The Cold-Lip Source for Aluminum promotes freezing of aluminum at the crucible lip before it can creep out and damage the source.
For demanding applications, or when large source capacities are required, Dual Filament or SUMO Sources are recommended.
Performance and Benefits
Single Filament Sources offer good performance and value for general purpose applications. The Standard Filament Source provides better accuracy and stability due to the band-style thermocouple leading to increased thermal stability. The hot-lip heating in a Modified Filament Source reduces gallium- and indium-related oval defects. It also improves the stability and reproducibility of evaporation of other materials by preventing condensation in the crucible.