In low melting point or low decomposition temperature materials with low thermal conductivity the local heating generated by the electron beam of an electron microprobe induces permanent damage to the sample and thus makes the technique unreliable. An aluminum layer of 1-μ thickness helps to dissipate the heat and lowers the temperature to tolerable levels. This paper analyzes the heat-flow problem of the two-layer target, consisting of the sample and the deposited aluminum layer, by the method of images and presents results for various thicknesses of aluminum. Experimental evidence is presented from HgTe and a Bi-Sb-Te-Se alloy on the usefulness of the method.