High Energy Probes of Semiconductors: X-Rays

Abstract

For structural studies, the most useful probe of the solid state is the high energy photon. Only short wavelength photons can be used to determine the crystal structure of an ordered material, and it is not possible to give a full description of the electronic structure of a solid without some knowledge of the atomic coordinates. Fortunately, using computer automated x-ray probing devices, it is almost a routine task to obtain accurate crystal structure information. In fact, with new bright sources of x-rays, it may also become possible to obtain surface structural information. Another useful function of x-rays is to probe the valence charge density of a semiconductor. The experimental determination of valence charge densities is difficult but not impossible, and some very good data exist for diamond and zinc-blende semiconductors. Finally, x-rays can be used to monitor temperature effects by studying Debye-Waller factors.