The patented Veeco Valved Cracker for Arsenic is the source that revolutionized solid source MBE. Used in hundreds of MBE systems worldwide, it is the industry standard arsenic source for R&D and production. The innovative design of the Veeco Valved Cracker provides the convenience of a gas source with the safety of a solid source. The solid arsenic is heated within the large capacity crucible to generate beam flux. A refractory metal needle valve regulates the gas flow into an independently heated cracking zone. Adjustments to the cracking zone temperature may be performed to generate either As4 or As2 beams.
- Patented design with nearly 1000 in the field
- Advanced flux modeling capability enables a custom designed nozzle based on the system geometry and use case
- Nozzle design optimizes material utilization and flux uniformity
- Mechanical flux control for near instantaneous response
- More economical to operate than a standard source
With recent enhancements, the Mark V Valved Cracker for Arsenic incorporates a nozzle that provides excellent flux uniformity and reduced material waste. This improvement in material utilization results in the following:
- Material cost savings
- Longer campaigns
- Shorter system cleaning time
- Less hazardous waste generation
- Reduced memory effects
- Lower particulate levels and flaking
Reduced system window coating the Veeco Valved Cracker for Arsenic is available in a range of sizes for compatibility with all MBE systems. In many cases, more than one size is offered to accommodate applications with high arsenic usage. The exit nozzle is customized to the specific MBE system for excellent flux uniformity across a wafer or a platen. A Veeco SMC-II Automated Valve Positioner is recommended for use with this source for reliable, automated control of the needle valve.
Performance and Benefits
The Valved Cracker for Arsenic optimizes control over the growth process by using a needle valve for near instantaneous flux modulations and complete flux shut-off. The source may be idled continuously at operating temperature without depleting the charge material. With mechanical flux control, rather than the thermal control used for conventional open sources, the charge capacity may be arbitrarily large without limiting the responsiveness of the source.
Demonstrated benefits include:
- More control over the growth process
- Greater productivity
- Longer growth campaigns
- Reduced As consumption
- More thorough charge outgassing
- Elimination of unintentional as incorporation into heterostructures
- Better use of in situ diagnostic tools