William Francis Kane

Chemical Vapor Deposition of Copper from an Organometallic Source

High purity copper has been deposited from trialkyl phosphine complexes of cyclopentadienyl and methylcyclopentadienyl copper(I) by thermal chemical vapor deposition (CVD). Films as thick as 4.4 μ m have been deposited at growth rates of up to 2000 A/min with resistivites typically 2.0 μ Ω cm, just slightly higher than bulk copper. Depositions were carried out at substrate temperatures between 150 and 220 °C on a variety of substrates including Si, SiO 2 , polyimide, and Cr/Cu. At low substrate temperatures, copper film growth appears to show some selectivity for transition metal surfaces. An activation energy of 18 kcal/mole has been measured for film growth on Cu seeded substrates. CVD copper films have been characterized by Auger spectroscopy which showed that carbon and oxygen levels are below the limits of detection. Transmission electron microscopy revealed that the copper grain size was ∼0.6 μ m and the grain boundaries are free of precipitates. Films show good conformality.

Thickness dependent dielectric properties of Sol-gel prepared lead lanthanum titanate films

Abstract A series of lead-lanthanum-titanate films (PLT, Pb0.65La0.28Ti0.96O3) films of differing thickness were prepared on Pt/Ti/SiO2/Si substrates using sol-gel techniques. One to six layer films with a layer thickness of 330 A/layer were deposited by spin-coating from a partially hydrolyzed metal alkoxide solution. After each layer was applied, the films were annealed using rapid thermal annealing (150°C/sec temperature ramp, 1 minute at 700°C, O2 atmosphere). The films were characterized by X-ray diffraction (XRD), electrical measurement of dielectric constant, dissipation factor and leakage current, and cross-sectional transmission electron microscopy (TEM). For all films, only the perovskite phase of PLT was observed by both XRD and TEM. The films showed a strong [100] orientation on the [111] textured Pt substrates. Electrical measurements determined the dielectric constant at 200 kHz for films 1000 A thick and thicker to be ∼550. These films had leakage current densities of less than 1×10−7 amp/c...

Preparation of strontium titanate films by MOCVD

Abstract Strontium titanate films have been prepared by MOCVD from Sr(thd)2 and titanium isopropoxide. Ammonia was used as a carrier gas for the strontium precursor, and argon as the carrier for the titanium precursor. The films have been deposited on silicon and on Pt/Ti/SiO2/Si substrates at 700°C using N2O as the oxidizing atmosphere. The films have been characterized by X-ray diffraction (XRD), Rutherford backscattering spectroscopy (RBS) and electrical measurements. X-ray diffraction showed that the crystallization of the films was strongly dependent on their composition. Films having a ratio Sr:Ti>0.8 crystallized in the perovskite phase, while films containing a lower Sr:Ti ratio did not crystallize at all. The diffractograms of strontium rich films showed that they contained also strontium oxide and strontium carbonate crystalline phases. However no crystalline phase could be identified in the titanium rich films. RBS measurements indicate a strong interaction between the strontium titanate and th...