Abstract
Film thickness dependence of the Curie temperature of nickel films is investigated under variousexperimental conditions. The residual gas is found to be effective in reducing the Curie temperature of the films when the ratio of pressure to deposition rate exceeds 1×10-6 Torr· Å-1·sec. The decrease of the Curie temperature with decreasing film thickness is more pronounced as the outgassing of substrates is less sfficient. When thefilms are deposited on thoroughlyoutgassed substrates and not exposed to air the Curie temperature is nearly constant for films of thickness above 50Å. When the films are exposed to air, a lowering of the Curietemperatute occurs for thin films. The lattice constant of these thin films is increased and the largest increment observed is 0.7% of bulk value. A correlation is found between the lattice constant and the Curie temperature.
