We report on the electron stimulated adsorption of oxygen produced by the electron beam of an Auger spectrometer on Cu(100) samples at approximate to 100 K and 300-350 K. The O-KLL, as well as the Cu LMM and M23VV Auger signals were monitored. The Cu target was discontinuously exposed to O-2 up to saturation of the O-KLL signal (440 langmuir, L), irradiating between doses with electron-beam energies in the range 100-2000 eV. The M23VV doublet of Cu at 59-61 eV became unresolvable as the exposure of the adsorbed O-2 to the electron beam progressed. The effect of O-2 with the sample at 100 K was practically the same as that previously found for H2O with the sample at 350 K, the kinetics of the process being governed by the sticking coefficient. A lateral composition profile taken after stabilization by annealing at 300 K showed a circular region centered at the point of incidence of the beam in which the O-KLL signal had values approximate to 20 times higher than all around. This surface chemical modification was stable upon annealing during 10 min at 573 K, but annealing at T > 1000 K practically restored the initial resolution condition of the M23VV doublet. From the collision number of O-2 molecules, considering (i) the low sticking coefficient on Cu(100), and (ii), that the chemisorbed species are atoms, an overall efficiency of approximate to 10(-6) can be estimated for the electron-beam assisted oxidation of the bulk.