A MECHANICAL PROBE FOR ACCURATE SUBSTRATE-TEMPERATURE MEASUREMENTS IN MOLECULAR-BEAM EPITAXY

A mechanical probe for temperature measurements in the range 300-530-degrees-C has been developed in order to control the substrate temperature in a molecular-beam epitaxy system. In this temperature range conventional measuring devices like standard thermocouples and pyrometers do not provide the absolute temperature of the substrate. The probe makes contact with the substrate in a nongrowth position. To balance the heat flow from the sample holder to the probe, two thermocouples and a compensating oven are integrated with the probe. A reproducibility of +/- 2-degrees-C can be achieved when measuring the absolute temperature.