High-resolution imaging of electronic devices using line modified-asymmetric crystal topography (LM-ACT)

Summary

X-ray topographic measurements are reported for implantation and superstructure details in an otherwise perfect, parametric, single-crystal device. Image contrast in topographs is attributed to the combined effects of device implantation or deposition strains in the host crystal, X-ray absorption, and surface shadowing or edge enhancement of the X-ray beam and, also, perfection of the lattice at the atomic scale. Stereo-pair images have been obtained to provide depth measurements. Sequential topographs have been utilized after various steps in device fabrication, ultimately, to monitor processing procedures. Comparison is made with dynamical theory calculations. The X-ray penetration depth and micrometer size of the thin-film nuclear emulsions used to record the diffraction images are shown to be important factors in limiting spatial resolution.