Published online by Cambridge University Press: 16 February 2011
Semiconductor materials and devices are commonly investigated by transmission electron microscopy to obtain microstructural information. The results are useful only when a thinned sample is representative of the parent material. The technique of ion milling can introduce artifacts arising from beam heating during specimen preparation. A survey of specimen temperatures during argon and iodine ion milling of silicon, indium phosphide and gallium arsenide was made by encasing a thermocouple in a specimen and varying ion beam energy and beam angle of incidence. The results indicate, for example, that the typical temperature of silicon specimen preparation is less than 140°C. By decreasing the beam energy and incident angle, the milling temperature can be reduced. Design improvements on the ion mill can also sink heat away from the specimen.