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Interface dislocations present in a Si0.85Ge0.15/Si sample have been imaged using the channeling scanning transmission ion microscopy (CSTIM) method with a 2 MeV proton beam 200 nm across. Groups of parallel dislocations gave dark bands of contrast down to ∼1.5 μm across, the contrast arising from dechanneling of the beam by the bent lattice planes. Tilting of the sample caused the band contrast to change and gave quantitative data concerning the local bending of the lattice planes. A low‐angle boundary model was developed to describe the effect of the groups of dislocations on the channeling contrast. Channeling and topography contrast were obtained from mesa structures present on the sample. Improvements in the sensitivity of the CSTIM method are discussed. The dislocations in the sample were initially characterized by transmission electron microscopy.

Ionizing radiation such as photons, keV electrons, or MeV ions can generate electron‐hole pairs in semiconducting material. The high penetrating power of MeV light ions allows them to generate electron‐hole pairs from deep within intact microelectronic devices, so images can be formed of the device active areas with very little degradation of the spatial resolution of the focused MeV ion beam. Furthermore, the ion‐beam‐induced charge (IBIC) image contrast is not strongly affected by the energy loss through the overlying device layers. This article is the first to demonstrate the capability of a nuclear microprobe to generate IBIC images of the active regions of devices through the passivation and metallization layers. The effect of the carrier generation volume on IBIC resolution is assessed. The ability of IBIC to align the major crystal axes of semiconductor samples is shown, and the effect of ion‐induced damage on IBIC image contrast is considered.

The recently developed ion beam induced charge technique has been used to image bands of misfit dislocations in a 4 μm thick epitaxial layer of Si 0.875Ge0.125 grown on a Si substrate. The smallest resolvable bandwidth is 0.8 μm under present conditions. The factors which presently limit this value, and methods for improving it are discussed.

This paper shows ion channeling images of the strain field produced by precipitate particles in a crystal matrix. Images have been produced by mapping the energy of 3 MeV protons transmitted through a thinned silicon crystal containing colonies of copper silicide particles, with the incident beam at or close to planar channeling directions of the lattice. Features of the precipitate contrast observed as a function of beam tilt angle away from channeling alignment are qualitatively explained using a model based on symmetrical plane rotation of the crystal lattice around the colonies. © 1996 American Institute of Physics.