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Crystalline SiC films are typically deposited on substrates at elevated temperatures by sputtering, pulsed laser ablation, thermal chemical vapor deposition (CVD) and CVD plasma assisted. However, high temperature may adversely affect the substrate, especially when metal alloys are used. To maintain substrate properties (temper, dimensional tolerance, etc.), a low deposition temperature is required. In this work, silicon carbide is formed from simultaneous sputtering of silicon and laser ablation of graphite onto suitably biased substrates at room temperature. The advantage of this method lies in the independent selection of plasma characteristics of both magnetron sputtering and laser ablation to achieve the required stoichiometry and species energetics. Desirable film properties such as good adhesion and crystallinity normally requiring elevated substrate temperatures are obtained via the energetic bombardment of the growing film. In this study, films are grown on M50 steel substrates at biasing varied from 0 to −300 V permitting control over crystallinity, chemistry, and stoichiometry. X-ray photoelectron spectroscopy (XPS) analysis shows the existence of silicon carbide bonds and x-ray diffraction analysis demonstrated the growth of crystalline (prominently alpha polytypes (4H–SiC, 6H–SiC) films at room temperature. In addition, XPS is used to find percentage of SiC bonds in the films. The optimum bias −100 V was found to favor crystalline growth in these films. Special emphasis is given to control of film stoichiometry as it relates to mechanical properties.

Ionized cluster beam deposition uses a beam of ionized, accelerated atom clusters to grow thin films. Earlier unsuccessful attempts at forming such cluster beams by homogeneous nucleation used 1 mm×1 mm nozzles at crucible pressures around 2 Torr. Recently, Gspann [Proc. German Phys. Soc. 3, 387 (1992)] and the authors [Appl. Phys. Lett. 61, 1180 (1992)] produced significant numbers of large zinc clusters by increasing the crucible pressure to the 1000 Torr range and using a converging‐diverging nozzle 18 mm long and 0.4 mm in diameter at the throat. The cluster distribution for a crucible temperature of 1180 °C peaked around an average of 2200 atoms per cluster. This distribution was measured by extending the previous deflected deposition method for average size to apply for the entire ionized fraction of the beam. Cluster velocity was nearly constant over the entire distribution in agreement with what would be expected for a homogeneous nucleation process. Over 99% of the ionized beam was in the form of...

Shrinkage of ultralarge scale integrated circuit design rules to below 0.5 μm is placing new demands upon thin‐film interconnect, especially for filling vias in insulating material to conductors lying below. Selective area deposition which will lead to enhanced via filling is investigated here using cluster beams, with a distribution peaking at 2200 atoms in average size, in which every cluster is positively ionized. A positive repelling voltage is placed on a conducting plate immediately behind test substrates which consist of an insulator with overlying conductive test patterns held at ground. Depositing metal selectively coated the conductive patterns while the repelling voltage essentially eliminated deposition onto insulating areas.

During conventional ion milling of carbon thin films on Si or SiC, the carbon has a much slower milling rate than the Si, SiC, and the epoxy resin. As a result, the substrates were thinned much more rapidly than the carbon films. A solution suggested by several subscribers to the Microscopy Society of America's Microscopy Listserver among others was to reactively ion mill the samples with a 20–25% oxygen-argon gas mixture. Is this the best inert gas to use? Neon has a mass that is between Si and C and therefore should impart a higher energy transfer to the C atoms than Ar. To determine whether the mass of the inert gas is important in balancing the milling rates, four gases were used to ion mill samples of a PLD DLC film with a nominal thickness of 0.5 μm. For improved adhesion of the films to the Si substrate, an initial 2 nm of Ti and a nominal 0.5 μm thick layer of TiC was grown using a combined PLD and magnetron sputtering technique prior to the PLD DLC.1,2 The gases were 100%Ar, 100%Ne, 75%Ar-25%O2, and 75%Ne-25%O2. Using the Tripod Polisher, the samples were polished flat using typical conditions and the surfaces examined by atomic force microscopy and compared. TEM samples prepared by single-sided dimpling prior to ion milling were prepared using the gas composition which gave the best results with respect to the AFM. A methodology is established for determining ion milling conditions for samples having layers of different compositions.

Ionized cluster beam deposition uses a beam of ionized, accelerated atom clusters to grow thin films. Earlier unsuccessful attempts at forming such cluster beams used 1×1 mm nozzles at crucible pressures around 2 Torr. Recently, Gspann [Proceedings of the Ger. Phys. Soc. 3, 387 (1992)] produced zinc clusters by increasing the crucible pressure to the 1000 Torr range and using a converging–diverging nozzle 18 mm long and 0.4 mm in diameter at the throat. The work reported here uses electron bombardment heating and deflected deposition cluster measurement. Results indicate significant numbers of zinc clusters, 1400 atoms in average size, in general agreement with Gspann.