The Janis cryogen-free series probe stations provide the researcher with vacuum and cryogenic probing capabilities without requiring the use of liquid cryogens. 10 K and 4 K cryocoolers utilize proven Gifford-McMahon (G-M) technology for reliable and affordable sample cooling. Typical applications include MEMS, nanoscale electronics,
superconductivity, ferroelectrics, material sciences and optics.
Every cryogenic probe station requires a cryostat, and Janis has been a world leader in the design and fabrication of research cryostats for over 45 years. The successful application of this extensive cryogenic design experience now enables cooling and probing of samples without the use of cryogens, and without the introduction of unwanted vibrations and noise to the sample. The sample is mounted on a removable sample holder (chuck); sample chucks are available in a variety of configurations including grounded, coaxial, and triaxial. The sample is fully surrounded by a thermal radiation shield, resulting in the lowest possible sample temperature. The cryocooler is connected to the chuck and thermal shield via proprietary low vibration / high thermal conductivity links. Silicon diode thermometers and a high wattage heater are used to monitor and control the sample temperature stability within 100 mK at any temperature within the operating range.
Micromanipulated Translation Stages
Four independent X, Y, Z stages provide precise control over the probe motion within the range of travel. Each stage includes graduations in increments of 10 – 12.5 microns, with typical useful resolution of 5 – 6.25 microns. Stages used for microwave probes include theta rotation adjustment for planarization of the probe.
A wide variety of probe options are available and different options can be specified for each probe stage. Typical configurations include:
1. LOW FREQUENCY (DC). Tip diameter, radius, and material can be specified by the
user to match a specific application and pad size.
1.1 CX: Coaxially shielded low frequency probe with BNC feedthrough and 50 ohm coaxial cryogenic cable.
1.2 TX: Triaxially shielded low frequency probe with triax feedthrough and 50 ohm triaxial cryogenic cable.
1.3 KEL: Kelvin probe, available in either CX or TX configuration. The KEL probe includes two coaxial or triaxial cryogenic cables joined at the probe holder, and wired to
separate BNC or triax feedthroughs. One cable is used for forcing current (or voltage) through (or across) the device under test (DUT), and the other cable is used to sense the voltage (or current) passing across (or through) the DUT. KEL probes are typically used for low resistance measurements in order to eliminate cable resistance from the