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A detailed model for the operation of a flow type atomic layer deposition (ALD) reactor is developed and tested with the growth of tantalum pentoxide thin films. The model incorporates evaporation, diffusion, and convection phenomena in mass transport and a kinetic description of the surface reactions and film growth. The theory gives a quantitative estimate for the deposition rate and thickness uniformity of the film. The necessary conditions for an ALD operation are discussed. The experiments support the predictions provided a pure ALD mode is prevailing.

CaF2, SrF2, and ZnF2 thin films have been deposited on glass substrates for the first time using atomic layer deposition (ALD) at temperatures between 260 and 400°C. The source materials used are alkaline earth β‐diketonates, zinc acetate dihydrate, and hydrogen fluoride in nitrogen atmosphere. The growth rate of films varies from 20 to 90 pm/cycle depending on materials and temperature. The crystallinity, orientation, stoichiometry, atomic density, optical and electrical properties together with growth properties of the films have been characterized. Also, multilayer structures with alternating materials of high ZnS and low (fluoride) index of refraction have been prepared by ALD.