evacuated to a residual pressure better than lO mbar or with

velocity is found to be 3xl06 cm/s and is not influenced by the presenceof oxygen in the studied pressures interval. The lack of differences in.the plasma behavior when ablation takes place in vacuum or in oxygenpressure is consistent with the low oxygen content found in the films.1.INTRODUCTIONLaser evaporation of solid targets is a recently developed techniqueto grow thin films of technological materials1'2. Among others, it hasbeen succesfully applied to grow high temperature superconducting oxidefilms, hard and hydrogen—free diamond—like films, NTi ,