ZN50R-CVT DC/RF Flexible Probes

ZN50R-CVT DC/RF flexible probe Developed in collaboration with TOYO Corporation of Japan, the Lake Shore patented Model ZN50R-CVT automatically compensates for probe arm temperature expansion of thermally anchored probes, significantly improving measurement reliability and enabling measurement automation over wide temperature ranges.

The operational temperature range for keeping the ZN50R-CVT probe tip landed on a sample is defined as starting at the lowest desired temperature and warming the sample stage through the range. The starting temperature may be anywhere in the probe station’s overall sample stage operating limits. The ZN50R-CVT probe’s ability to keep the tip stable while landed on a sample is dependent on both the probe tip (material/radius) and on the probe station model. Composition of the landing pad is also critical to the probe performance. Specifications are given for gold plated copper. Harder or softer pads may affect temperature range.

Probe model	Tip material	Tip radius (µm)
ZN50R-CVT-10-W	Tungsten	10
ZN50R-CVT-25-W	Tungsten	25
ZN50R-CVT-25-W-AU	Gold-coated tungsten*	25
ZN50R-CVT-25-BECU	BeCu	25

*Gold-coated tungsten probes are best for soft contact material such as gold, silver, and tin.
Maximum frequency is 50 MHz with ZN50-G or ZN50-T cable.
Maximum frrequency is 1 GHz with HMWC-07-00K cable.

	CPX, CPX-VF, CPX-HF, CRX-VF	TTPX, EMPX, FWPX, CRX-6.5K, CRX-4K, CRX-EM-HF
ZN50R-CVT-10-W	Δ200 K	Δ100 K
ZN50R-CVT-25-W	Δ400 K	Δ150 K
ZN50R-CVT-25-W-AU	Δ400 K	Δ150 K
ZN50R-CVT-25-BECU	Δ200 K	Δ100 K

Adjusting for probe travel while making measurements easier

Lake Shore CVT flexible probe With probe arms thermally anchored to the sample stage, a standard probe tip may move as much as 400 µm as the sample stage warms from 4.2 K to room temperature. This prevents you from making automated variable temperature measurements, as probes have to be lifted and re-landed for any significant temperature transition.

Stable tip position Lake Shore’s patented CVT (continuously variable temperature) probe design absorbs probe arm movement caused by thermal expansion and contraction. The result is a stable probe tip landing position throughout variable temperature cycling.

Continuous measurements CVT probes allow you to perform continuous variable temperature measurements, which means faster and more automated experiments. You spend less time adjusting probe positions and more time conducting research. Retrofittable onto existing platforms, CVT probes enhance the overall functionality of your Lake Shore probe station by making many of your measurements easier and more convenient to perform, as well as enabling new measurement applications.

Increased efficiency plus new measurement types

Fast and convenient The ZN50R-CVT probes allow you to take continuously variable temperature measurements without lifting and repositioning your probes each time you make changes to sample stage temperature. Configure your measurement, program the sample stage temperature rate of change in your temperature controller, and go.

Increase measurement functionality In addition to improved efficiency and faster results, measurement uncertainty is greatly reduced by eliminating the variability of repeated contact landings. Even experienced users with good technique cannot totally eliminate contact resistance variation on every probe landing. Measurements including Hall effect, gated Hall, IV, AHE, MR, DLTS, CV, photoluminescence and Seebeck effect are much easier and more convenient to perform.

Comparison of standard probes with CVT probes

In a comparison between standard ZN50R probes and the new CVT probes, you can see that the standard probes would need to be repositioned before the arms expand enough to move them off the landing position. The CVT probes flex and maintain contact with the desired location.

Patented CVT tip measurement results

The figure below demonstrates the real-world measurement performance of the ZN50R-CVT probes. Hall mobility versus temperature was derived, comparing the ZN50R-CVT probes to Lake Shore standard ZN50R probes. Measurements were taken on a Lake Shore Model CPX-VF vertical field probe station. The ZN50R probes were lifted during temperature changes and re-landed once the temperature settled, requiring fourteen different operator interventions. The ZN50R-CVT probes were landed at 20 K and left on the sample through the temperature range of 20 K to 300 K with no operator intervention. For both experiments, temperature was ramped in point-by-point mode: the setpoint was changed, temperature allowed to settle, and measurements were taken.

You don't have to constantly lift and re-land CVT probes

With patented ZN50R-CVT probes you don’t have to constantly lift and re-land during measurements

Landing a CVT probe