Solution deposition of thin solid compound films by a successive ionic-layer adsorption and reaction process

Abstract

The process is intended to grow polycrystalline or epitaxial thin films of water-insoluble ionic or ionocovalent compounds of the C_mA_n type by heterogeneous chemical reaction at the solid-solution interface between adsorbed Cⁿ⁺ cations and A^m− anions. The process involves an alternate immersion of the substrate in a solution containing a soluble salt of the cation of the compound to be grown and then in a solution containing a soluble salt of the anion. The substrate supporting the growing film is rinsed in high-purity deionized water after each immersion. Polycrystalline and epitaxial thin films of ZnS and CdS have been deposited following this process at room temperature on different substrates.