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Examines the formation of high-quality thin films of germanium by pulse laser evaporation. Characteristics of films deposited on 300 degree Celsius substrates; Effect of energetic ions, observed in the vapor stream generated by laser-induced plasma, on nucleation and bulk-film growth; Comparison of films deposited on ambient temperature substrates by laser evaporation to the film formed by thermal evaporation.

Presents a study which examined the microstructure and composition of the silicon dioxide/titanium dioxide and digital gradient-index films using transmission electron microscopy. Growth of the digital structures; Modification of the properties of dielectric thin films; Results of Auger electron spectroscopy.

Discusses a growth technique for growth of high-transmission, high-resistivity cadmium sulphide and Cd[sub1-x]Zn[subx]S. Optimum growth conditions for CdS; Instrument used to measure the optical transmission of the Cd[sub1-x]Zn[subx]S.

The behavior of codeposited thin films of ZnSe/LaF(3) and Si/ZnSe has been investigated. Mixed ZnSe/LaF(3) films are polycrystalline with intermediate compositions with moderately high compressive stress (1500-2000 kg/cm(2)). Mixed Si/ZnSe films are amorphous with intermediate compositions with low compressive stress (<1000kg/cm(2)). Optical properties of the ZnSe/LaFcm(3) system vary monotonically with composition, but those of the Si/ZnSe system do not, which is explained by the possible chemical reaction of the two species.

Composition dependent structural, optical, and mechanical properties of codeposited thin films were studied in the Si-YF(3) and ZnSe-SrF(2) systems. Intrinsic stress varies nonlinearly in both systems. In the Si-YF(3) system, the stress becomes slightly compressive for intermediate compositions, even though it is highly tensile in the pure constituent thin films. In the ZnSe-SrF(2) system, optical scatter and intrinsic stress exhibit abrupt changes at approximately 60-vol % SrF(2), accompanied by a change in the dominant crystalline orientation. Possible structure-property relationships and composition ranges for practical applications of thick films are also discussed.

Intrinsic stress and microstructure of mixed composition films were investigated for several binary systems of IR optical materials. These properties were measured for the entire range of compositions and for mixing obtained by codeposition and by layering of alternate pure components. The variation of stress with composition was observed to be significantly different, depending on the method of mixing. Microstructural analysis revealed a corresponding difference in the grain structure of the films. Low compressive stress films were obtained by coevaporation of high tensile stress materials. These can be used to produce thick and mechanically stable gradient-index optical coatings.

Rugate filters are optical thin film interference structures with sinusoidal refractive index profiles. Two-wavelength reflection filters have been fabricated by codeposition of SiO(2) and TiO(2). Composition modulation was monitored and controlled using quartz crystal rate controllers. The resulting filters exhibited two well-defined stopbands. Microscopic examination revealed that the structure is glasslike without pronounced thin film microstructure.

A method for depositing patterned infrared thin film spectral filters directly onto substrates at low temperatures (200 degrees C) is described. Energetic deposition methods (ion-assisted and laser-assisted) were used to avoid heating the substrates, while a multilayer photoresist lift-off technique was applied to pattern the structures. The process produced durable films capable of surviving harsh processing conditions. This is a promising method for depositing patterned coatings directly onto infrared focal plane detector arrays.