Laser generated defects in (Al,Ga) As have been investigated by photochemical wet etching and TEM measurements. Photoetching reveals a 500 nm wide zone in the center of the processed area where according to laser power either a luminescent or a nonradiative defect is present. In the adjacent regions (approximately 10 mu m wide) where the native luminescence is reduced, a third nonradiative defect is probably present. The luminescent defect has an etch rate similar to unprocessed materials, the other two an enhanced one. TEM measurements do not reveal any macroscopic defects (dislocations, microcracks, precipitates, etc. ) but 0. 5 mu m wide lines are detected which show weak strain contrast. The visibility of the lines depends on the sample thinning process. From TEM it is concluded that the three defects are point defects or point defect complexes.