The optical functions of several forms of thin-film silicon (amorphous Si, fine-grain polycrystalline Si, and large-grain polycrystalline Si) grown on oxidized Si have been determined using 2-channel spectroscopic polarization modulation ellipsometry from 240 to 840 nm (∼1.5–5.2 eV). It is shown that the standard technique for simulating the optical functions of polycrystalline silicon (an effective medium consisting of crystalline Si, amorphous Si, and voids) does not fit the ellipsometry data.

The optical properties of GaAs"Sbl "alloys grown across the entire concentration range by multitarget sputter deposition are reported. X-ray diffraction, optical absorption, and Raman spectra show the samples to be single-crystal, single-phase alloys for all x, including those in the miscibility gap. Alloy lattice constants are found to vary linearly with concentration. The direct I -point energy gaps, determined from optical-absorption measurements, show significant negative bowing.Contrary to previous reports, the Raman spectra exhibit two-mode behavior throughout, including a local mode of As in GaSb and a resonant mode of Sb in GaAs. An analysis of peak frequencies and line shapes versus concentration is given in the context of disorder effects. %e observe broadenings much less severe and asymmetric than those seen in similar systems and usually interpreted in terms of k&0 density-of-states activation. The observed adherence to zone-center selection rules for all x, suggests a more accurate interpretation to be one involving the k =0 spectral projection of the density of states.

Manufacturing a patternable metallized substrate for tungsten ultralong field emitter array by use of the double ion beam deposition method A permanent magnet electron cyclotron resonance microwave plasma source has been coupled to a copper sputter target to produce ionized copper fluxes for submicron integrated circuit metallization. A custom launcher assembly allows the use of microwave powers up to 5 kW in a metal deposition environment to produce plasma densities Ͼ10 12 cm Ϫ3 , well above the cutoff density at 2.45 GHz of ϳ1ϫ10 11 cm Ϫ3 . Six hundred nm, 1.1:1 aspect ratio features have been filled with copper, and 250 nm, 6:1 aspect ratio features have been successfully lined. Copper ionization fractions for the conditions used for lining and filling, determined by a combination of Langmuir probe measurements and optical emission spectroscopy, are between 10% and 35%.

Hard boron suboxide thin films were deposited in an electron cyclotron resonance (ECR) microwave plasma system at substrate temperatures below 300 °C. A high-temperature effusion cell, operated at 2200°–2250 °C, was used for injection of boron downstream of an Ar/O2 ECR plasma. B ion bombardment is estimated to have been up to 6% of the total boron flux, and Ar ion bombardment is estimated to have contributed ∼100 eV/deposited atom. Boron suboxide films with oxygen concentrations of 11% exhibited hardnesses up to 30 GPa, equal to sapphire and near that of pure boron. The hardness/modulus ratio was 0.1, significantly better than that of sapphire (0.067) or solid boron (0.074), indicating these films may be of interest for a variety of tribological applications.

Growth of Si and Ge thin films by laser-induced chemical vapor depositionEpitaxial Ge and Si films have been grown by primary ion deposition from laser-induced plasmas. The plasmas were formed by focusing 15 ns, 10 7 _10 8 W em -2, pulsesof5 eV photons frama KrF excimer laser onto Ge or Si single crystal wafer targets. Time-of-flight, current-voltage, and filmthickness distribution measurements established that neutral atoms and ions were emitted from Ge targets with mean velocities of 1,0-1. 6 X Wf> cm s --I (corresponding to average kinetic energies of 40 to 100 e V) in a distribution that was strongly peaked in the direction normal to the target surface. Macroscopic (-1 {.lm diam) particles were also emitted. A shutter, synchronously triggered with the laser pulses through a delay circuit, was used as a velocity filter for removing from the beam particles with velocities up to 1.2 X 10 4 em s -1. Epitaxial Ge films were grown on semi-insulating (100) GaAs substrates at temperatures between 300 and 450'C and epitaxial Si was grown on (100) Si at 700 °c. Deposition rates were typically 0.5-1 f.tm h --I. Hall effect measurements carried out on the Ge/GeAs heterostructures showed that the Ge films, -1 !lm thick, were p type with room temperature carrier concentrations of ~ 1 X 10 18 cm -3 and hole mobilities of -150 cm 2 /V s.

Optical emission spectroscopy is used to investigate trends with changes in processing parameters for Ar/Cu plasmas in an electron-cyclotron-resonance (ECR) plasma deposition system. The primary motivation for this work is to monitor trends in ionization fractions for copper deposition plasmas using a noninterfering diagnostic tool. The system, which consists of a solid copper sputter target coupled to a permanent magnet ECR microwave plasma system, is operated in the range of 1–6 mTorr argon with net microwave input power of 500–1500 W. Emission from the following excited states is monitored: Ar neutrals (696.5 nm); Ar ions (488 nm); Cu neutrals (521.8 and 216.5 nm); and Cu ions (213.6 nm). Cu ion emission and Cu neutral emission monotonically increase with net microwave input power but at slightly different rates for different pressures, while argon-ion emission as a function of pressure shows a broad peak around 4 mTorr. The ratio of Cu ion emission to Cu neutral emission is used as an indicator of the relative ionization efficiency for Cu and peaks near 5 mTorr. Spectroscopic estimates of electron temperature differences between pure Ar and Ar/Cu plasmas are also presented.

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Nanoindentation and nanoscratching experiments have been performed to assess the mechanical and tribological behavior of three thin film materials with potential application as wear resistant coatings for magnetic disk storage: (1) hydrogenated-carbon (CHx); (2) nitrogenated-carbon (CNx); and (3) boron suboxide (BOX). The hardness and elastic modulus were measured using nanoindentation. Ultra-low load nanoscratching tests were performed to assess the relative scratch resistance of the films and measure their friction coefficients. The mechanical and tribological performance of the three materials are discussed and compared.