Atom depth distributions resulting from the implantation of 29Si, 32S, 32Se, and 130Te ions within ∼0.05° of the 〈110〉 and 〈100〉 directions of the GaAs crystal have been measured by secondary‐ion mass spectrometry. The two lower‐mass ions were implanted at 150 keV and the two higher‐mass ions at 300 keV; all were implanted to a fluence of 3.0×1013 cm−2. Well‐defined maximum ranges and most probable channeled ranges Rc are observed in the 〈110〉 channeled distributions. The values of R0.1Nmax at Rc, chosen as a measure of the maximum channeled range, are 2.60, 1.60, 3.56, and 4.68 um, respectively, for the four ions. Background‐subtracted detection sensitivities for these four atoms in GaAs of l013–3×1014 cm−3 provide up to five orders of magnitude of dynamic range below the maxima in the depth distributions (the peaks in the random components).