LASER-STIMULATED PROCESSES IN METAL-CARBONYLS FOR METAL-BASED FILM SYNTHESIS

The laser induced decomposition chemistry of metal carbonyls has been the subject of numerous investigations. In the area of metal film depo sition, the gas-phase photolysis of carbonyls is an area of current in terest, owing to their large absorption cross sections in the UV wavel ength range. However, detailed analysis showed that the film compositi on reflects additional thermal and photochemical surface processes, wh ich need to be further elucidated. Although leading to higher film pur ities, the thermal decomposition of carbonyls in the presence of a las er heated substrate was less explored. Examples of laser-stimulated de position processes from metal carbonyls are presented, including the U V photolysis of Mo(CO)(6) at long exposure times and the thermal decom position of Cr(CO)(6). Some aspects related to Mo(CO)(6) decomposition in presence of silane are discussed, in connection with the synthesis of new metal-modified polymers. A comparative analysis of the propert ies of films obtained from Fe(CO)(5) by photolytic and thermal laser-i nduced processes indicates that specific growth mechanisms influence t he film structure and chemical composition.