UNEXPECTED EFFECTS OF FORCED HIGH NUCLEATION DENSITIES BY FLASH EVAPORATION OF GOLD ON NACL AND KCL SUBSTRATES

Gold was deposited slowly and simultaneously on air-cleaved NaCl and vacuum-cleaved NaCl and KCl crystals, portions of which had been covered with about 20 Å of gold by simultaneous flash deposition prior to the commencement of slow deposition 320°C substrate temperature. The epitaxy of gold on vacuum-cleaved NaCl substrates is enhanced by the higher nucleation density resulting from the flash deposition while the latter causes a deterioration of the epitaxy on both vacuum-cleaved KCl and air-cleaved NaCl substrates. It is proved that no effective substrate contamination results from the flash evaporation. It is suggested that a critical or epitaxial nucleation density exists for each deposit-substrate system. © 1969 The American Institute of Physics.