This source uses two independent filaments to heat the crucible, primary and tip, providing enhanced heating control. The tip filament is operated in hot-lip mode to prevent condensation at the crucible lip. In addition, the heat-shielding enclosure enables optimal source responsiveness and stability in the temperature operating range of 100-750°C.

• Patented design with more than 50 in the field
• Optimized for responsive performance at low operating temperatures
• Dual filament hot-lip heating to prevent condensation at the crucible orifice
• Excellent long-term flux stability with high vapor pressure materials

The Veeco Low Temperature Dual Filament Source for MBE uses two independent heaters to control the temperature variation along the length of the crucible. The primary heater filament heats most of the crucible. The tip filament heats just the mouth region of the crucible to compensate for the greater radiative heat loss in this area. The source is operated in hot-lipped mode to eliminate material recondensation at the crucible orifice, which can lead to source occlusion and beam shadowing.

The Low Temperature Dual Filament Source is enclosed in a heat-shielding package designed for optimal source responsiveness and stability in the operating range of 100-750°C. Temperature stability is critical with high vapor pressure materials, since even a small temperature variation produces a dramatic change in the flux.

The Low Temperature Dual Filament Source is also available in the high-performance SUMO design. See the “Low Temperature SUMO Source” data sheet for further details.

Performance and Benefits

The Low Temperature Dual Filament Source is precisely tailored to the demands of evaporating high vapor pressure materials.

Benefits include:

• Optimal performance at lower operating temperatures
• Rapid flux stabilization
• Excellent long-term flux stability

Dual Filament “hot-lip” heating prevents condensation at the crucible orifice. This has been proven effective with a number of “difficult” materials including antimony, tellurium, and lead compounds.