Direct-write atom lithography is a new technique in which resonant light is used to pattern an atomic beam and the nanostructures are formed when the atoms are deposited on the substrate. The characteristics of chromium atoms deposit on a substrateare are discussed. We simulated and analysed the characteristics of nanostructure under different laser power and on different y-plane. At the same time, the characteristics of nanostructure are analysed with respect to the effects of atomic beam divergence, the resulting full width at half maximum and contrast are shown under respective conditions.