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Simple procedures are described for the design of correction masks for broad beam ion sources of a known flux profile, where the mask is fixed and the substrate is rotating and also where the substrate is fixed and mask is rotating. The digitized maps of the test surfaces before and after etching are used to determine the experimental etch rate and the surface figure of the optical substrate, and also to test for convergence of the etched surface to some end figure.

Plasma deposited silicon nitride thin films were deposited at temperatures between 150 [degrees]C and 300 [degrees]C. Diagnostic microstructures were fabricated from the thin films using bulk micromachining, and the strain was calculated from optical measurement of postbuckling deflection. The results indicate that the residual strain of the thin films is dominated by film-substrate thermal mismatch, with the coefficient of thermal expansion monotonically increasing with decreasing deposition temperature. Metal-insulator-metal devices of variable area were also fabricated to measure the dielectric constant, which was shown to be independent of deposition temperature. The importance of these results to microsystems technology (MST) was briefly discussed. [1441] Index Terms--Amorphous materials, dielectric films, electric field measurement, microelectromechanical devices, micromachining, plasma chemical vapor deposition (CVD), silicon compounds, strain measurement, thin films.

Surface topography measurements using optical interferometry were made on polished samples of fused silica namely Zenrodur and single-crystal sapphire with area root-mean-square (rms) microroughness values from about 4 to 1 angstrom. The samples were then etched by ion-beam etching (IBE), removing the material in steps of 500 nm to a cumulative depth of 3000 nm.

A study conducted measurements of the transport properties of typical Bi-2223/Ag composite conductors produced by the standard powder-in-tube, roll/anneal, thermo-mechanical deformation process. The conductors have engineering properties that are similar to performance values reported by other research teams. Twisted round wire conductors exhibited isotropic magnetic field behavior with critical current values intermediate to those observed for the B//c and B//ab directions in untwisted wires.

Research was conducted to review the development of a superconducting quantum interference device (SQUID) magnetometer and to address the inherent problems associated with the use of SQUIDs in ground based and airborne electromagnetic systems such as operation and movement in the earth's magnetic field. The importance of the advantages for mineral prospecting in regions with a conducting soil cover or overburden typical of the Australian landscape is reported.

A scanning Hall probe magnetometry was used to measure the local distribution of the magnetic field component Hz(x) perpendicular to the plane of (Bi, Pb)-2223/Ag tape conductors that are carrying transport currents at T = 77 K. A characteristic current I* which corresponds to the critical current in the model was determined. The predictions of the critical state model is closely similar to the magnetic response of single-filament tapes carrying quasi dc currents.

The Josephson behavior of trench-patterned, double tilt-angle YBCO step-edge junctions is studied by measuring their current-voltage characteristics under the presence of applied magnetic fields. The measured data show that the mixed state in the junctions' superconducting films is responsible for the devices' hysteretic behavior. The data also indicate that flux penetration occurs in the presence of strong magnetic fields.

The characterization of multifilamentary, silver-sheathed (Bi,Pb) 2Sr2Ca2Cu3O(10+z) (2223) tapes prepared using the powder-in-tube process was carried out. The tapes, which reach lengths of up to 46 m., were also wound into a solenoid coil with 306 turns. Prior to and after this, observations of critical current, current density, uniformity and grain growth were made. The results showed that controlling the melt process and atmosphere leads to higher critical current densities in thin 2223 tapes.

Two method for the fabrication of step-edge junctions on MgO substrates are presented. The methods, which allow the predetermination of the critical current at the junction, use a titanium thin film rather than a photoresist as a mask during ion milling, thereby, resulting in excellent edge definition. Scanning electron micrography results show that the step angles of the junctions produced using the two methods are identical.

Force-displacement curves obtained from an ultralow-load microhardness instrument were used to determine the microhardness and Young's modulus of polycrystalline diamond and diamondlike carbon films. The results showed that the diamon film exhibited a hardness in the range of 80 to 100 GPa, while the Young's modulus was in the range of 500 to 533 GPa. The diamondlike carbon film properties exhibited a dependence on the ion energy available to condensing carbon atoms, such that increased ion energy resulted in increased hardness.

Nanoindentation was performed on plasma-deposited nitrogen-rich silicon nitride thin films deposited on various substrates between 150 and 300 °C. A very simple and effective depth-profiling method is introduced, which involves indentation of thin films deposited on substrates with different mechanical properties. The primary advantage of this method is that it avoids the complications associated with many of the complex mathematical models available to deconvolve thin film mechanical properties, while nevertheless allowing the user to visually identify thin film properties. This method is demonstrated on our thin films, which have a hardness between 14 and 21 GPa, and reduced modulus between 120 and 160 GPa. The initial rise in hardness at low contact depths, commonly attributed to an indentation-size effect, is shown to be due to elastic contact between the indenter and thin film surface. This demonstrates the perils of blindly following the 10% rule for hardness calculation. The contribution of elastic and plastic deformations from nanoindentation is used to clarify the physical meaning of hardness and reduced modulus. [ABSTRACT FROM AUTHOR]

Plasma deposited nitrogen-rich silicon nitride thin films were prepared at temperatures between 80 and 300 °C. The infrared transmission (400–4000 cm-1) was measured, and selected absorption bands were quantified through a multiple Lorentzian oscillator parametric analysis. It is observed that the concentration of silicon-centered tetrahedra bonded together through nitrogen atoms increases monotonically with increasing deposition temperature. A qualitative model is presented to highlight the impact of the active adsorption site density on the degree of stepped (ordered) nucleation at the vapor-film interface. The importance of this growth profile, in particular for micro-systems-technology, is discussed in conjunction with measurements of the biaxial modulus and residual stress of the thin films. A mechanism for residual stress controllability is also presented. The atomic concentrations of silicon, nitrogen, and hydrogen in the thin films were calculated using infrared calibration factors derived from the deposition temperature dependent condensation processes. The results for silicon nitride thin films deposited at 300 °C were observed to be similar in composition to silicon diimide. Additional observations of the infrared transmission characteristics are reported, which include the identification of silazane bridge characteristics for the absorption feature around 610 cm-1, which is typically associated with Si–H (bending) absorption. [ABSTRACT FROM AUTHOR]