SCANNING ELECTRON MICROSCOPE STUDY OF PARTICLE/SUBSTRATE THERMAL CONTACT.

A modulated electron beam has been used as a scanning heat probe to examine the thermal contact properties of solid/solid interfaces. The infrared radiation emitted from target spherical particles resting on a planar metal surface was measured as a function of electron beam modulation frequency. The results permit the evaluation of a thermal response time based on a simple model of the particle/substrate system. The model proposes that the principle cooling mechanism for small spheres is thermal conduction into the substrate through a contact zone which scales as the radius of the particle.