Abstract
Pronounced structure at large biases in the ballistic-electron-emission-microscopy (BEEM) current for Cr/GaP(110) is attributed to density-of-states effects in GaP. Quasielastic scattering at the Cr-GaP interface appears vital for the effect. Impact ionization in the GaP is invoked to explain the unusually large collector currents that can exceed the injected STM tip current.