The spatial arrangement of electric‐field domains in heavily doped GaAs‐AlAs superlattices was investigated by depth‐resolved cathodoluminescence (CL). By measuring the CL spectra for different excitation energies of the electrons, it is shown that the high‐field domain is located near the anode. A quantitative analysis of the CL intensities suggests that there is only one domain boundary in the sample. ©1995 American Institute of Physics.