VPF Series Cryostat Systems - Sample in Vacuum
Janis
Simple and inexpensive, the VPF cryostats provide a variable temperature sample environment with no valves or adjustments required. Designed with versatility in mind, the VPF cryostat is field-upgradeable with additional feedthroughs, windows or sample holders should experimental requirements change. Models for operation to 500 K, 700 K or 800 K are available.Standard Configuration
The Janis VPF cryostat is an inexpensive liquid nitrogen cryostat offering operating temperatures from 65 K to 800 K. Simple to use and refill, the VPF system uses a refill style displacer assembly and built-in heater to provide variable temperature capability. Temperatures below 77 K are achieved using an optional pumping manifold. High temperature capability is provided using special sensors and heaters.
Access to the sample compartment is provided by a quick disconnect clamp. Samples are mounted in a 3" diameter vacuum space (2.5" for VPF-800) and can be connected with cryogenic-service wiring (single conductor or coaxial). The four-way optical sample chamber (with a numeric aperture of 1.0) can be configured for reflectance or transmission measurements. Standard windows are fused natural quartz offering transmission from the UV to near- IR regions. Optional window materials can be installed to span the far/ mid- IR, VUV, and x-ray regions for a variety of spectroscopic measurements. The refill assembly permits refilling of the LN2 reservoir without affecting the controlled temperature.
Typical applications for the VPF include spectroscopy (photoluminescence, FTIR, UV- visible), materials characterization (resistivity, Hall Effect), as well as low- temperature imaging, microscopy, and component testing. Low cost, light weight, and portability make the VPF the ideal cryostat for multipurpose laboratories, demonstrations, and integration with existing instrumentation. VPF-100 and VPF-800 models are in stock for fast delivery to your site.
Custom configurations may be fabricated to fit restricted spaces (such as in a magnet system or spectrometer) or to allow the insertion of very large samples (such as semiconductor wafers or "cold plates" to cool several samples at once).
Standard Features
• Fused quartz windows• 4-way optical access (f = 1.0)
• Si diode thermometer and heater (thermocouple for VPF-800)
• Electrical feedthrough for thermometry
• Optical sample holder
• Refill assembly for continuous operation
• Complete system test
Optional Equipment
• Complete selection of ancillary equipment including temperature controllers, pumping stations, and storage dewars• Electrical measurement packages (sample holders, wiring, and feedthroughs)
• Pumping manifold for <77 K operations (see Other Configurations tab)
• Sample holder for DLTS (see fixed probe sample holder on Other Configurations tab)
• Additional bottom warm window port and quartz window
• Special adaptor for use with SuperTran liquid helium transfer line (see Other Configurations tab)
• Specially modified window block with large window as an option.
Specifications
Initial cooldown time (to 77 K) |
15 minutes |
Temperature range (1): |
|
VPF-100, S, ST |
65-500 K |
VPF-700S, ST |
65-700 K |
VPF-800 |
65-800 K |
LN2 hold time: |
|
77 K |
5 hours (VPF-100[T]: ~8 hours) |
100 K |
4.5 hours |
200 K |
2.5 hours |
Typical stability (2) |
± 50 mK |
Vacuum level required (3) |
10-4 torr |
Approximate weight |
7 lbs. (3.3 kg) |
(1) Temperatures <77 K with optional pumping manifold |