It has been shown through attempts to obtain pure carrier injection for the determination of electron and hole impact ionization rates (&agr; and &bgr;) that electroabsorption of recombination radiation can result in significant contamination of the injected currents in direct band‐gap semiconductors. The influence of this contamination on the values determined for &agr; and &bgr; and the requirements on the device structure to minimize this contamination are discussed.