Preliminary investigations have shown that a family of chalcogenides may be deposited in technologically useful thin film form by an inexpensive technique of spin deposition from solution. The materials which are amorphous and microstructure free retain many of the properties of the solute (e.g., As2S3, As2S2, As2Se3, As2Te3, or GeSe) from which they are prepared. Some of the materials have been demonstrated to be potentially useful for high resolution pattern replication in particular for microlithography.

The annealing behavior of spin coated thin films prepared from solutions of As2S3 dissolved in n-propylamine and n-butylamine has been investigated using IR, mass spectrometry, thermogravimetric analysis, and scanning calorimetry. As prepared films containing arsenic sulfide glass domains with surfaces reacted as alkyl ammonium salt undergo loss of amine and hydrogen sulfide during heating. H2S removal is believed to be accompanied by cross linking of glass domains resulting in a network glass containing only arsenic and sulfur.

Thin films that are substantially amorphous arsenic sulfide have been prepared by spin deposition from solutions of n-propylamine or n-butylamine. These materials have been investigated by nuclear magnetic resonance, infrared absorption, and elemental analysis. A structural model is suggested based on As2S3 clusters surrounded by amine as an amine salt.

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Oriented single-crystalline thin films of NiO and Fe304, and Fe304/NiO superlattices have been grown on cleaved and polished substrates of MgO(001), using oxygen-plasma-assisted molecular-beam epitaxy. We report the growth mode and structural characterization of the grown films using in situ reflection high-energy electron diffraction (RHEED) and ex situ scanning electron microscopy and x-ray diffraction. The (001) surface of MgO provides an excellent template for the pseudomorphic growth of these thin films and superlattices, for it has a very small lattice mismatch (0.3-0.9%) to the cubic rocksalt structure of Ni0 and to the half unit-cell dimension of the spinel structure of Fe304. Superlattices consisting of alternating layers of NiO and Fe304 have been grown with a repeat wavelength down to 20 0 A (approximately one Fe304 unit cell plus two NiO unit cells) thick. These superlattices exhibit strong crystalline ordering and sharp interface formation. RHEED pattern evolution in situ during growth indicates formation of the rocksalt NiO crystalline symmetry and then the spinel Fe304 crystalline symmetry in a periodic sequence as each material is being deposited. Our data indicate single-phase crystal growth in registry with the substrate, with films of overall cubic symmetry. Strain in the grown films exhibits interesting effects that clearly do not follow a simple elastic model.