Atomic force microscope measurement of channel temperature in GaAs devices

The channel temperature of Gallium Arsenide (GaAs) devices was quantitatively measured using scanning thermal microscopy (SThM), which is a variation of atomic force microscopy (AFM). The temperature of the devices was also characterized by infrared (IR) imaging and thermal modeling. It was found that the measured SThM temperature values agreed very well. With the calculated values from the model, and were higher than those found by IR, as predicted. In contrast to most published AFM results that have reported only qualitative and indirect semi-quantitative thermal information about the sample, the results presented here can be used directly to accurately determine an absolute temperature of the device at any point that can be probed at the top surface.