Temperature of sample with cool tips

The offset of the device temperature will depend on the number of probes landed on the device as well as the quality of the thermal link between device substrate and the sample stage. As an example: CRX-VF at 300 K stage temperature, with the sample substrate clamped to the stage, N-grease under the sample, and four probes landed on the device -- the device will be roughly 2 to 3 K colder than the stage. Without grease or clamping but the same probing configuration, that same device may be 10 K colder than the stage.

When working at room temperature and concerned about cooling the device through the arms, the probe anchors can be removed from the radiation shield stage and tied to the arms. This is not recommended when cooling the device to cryogenic temperatures.