The ability to fabricate spatially well-defined, patterned, metal films on various substrates is critically important for numerous microelectronics applications. For example, fabrication of metal contacts and conductors is required in microwave circuits, printed wiring board (PWB) circuitry, local and global chip interconnects, and other aspects of electronics packaging technology. 1 Metal patterns are routinely used to define the opaque regions of reticles and masks for optical and X-ray lithography. Thin metal films have also been used as protective layers for pattern transfer in integrated circuit (IC) lithography due to the extremely high etching resistance of metals and/or oxides derived from elements such as titanium, 2 tungsten, 3 zirconium, 4 and nickel. 5 Many processes exist for metal pattern fabrication. Metal deposition techniques include sputtering, evaporation, chemical vapor deposition, electrolytic deposition, and electroless (EL) deposition. Of these, EL deposition 6 is particularly attractive in manufacturing because it offers the ability to metallize nonplanar, insulating substrates with low-temperature processes using simple materials and equipment at low cost. Approaches for producing lithographic patterns of metals are of two general classes: subtractive and additive. The traditional lift-off method is an example of a subtractive process wherein metal is initially homogeneously deposited over an exposed and developed photoresist; the remaining resist must then be stripped to remove metal from the regions where it is not required. Additive metallization is a simpler and less wasteful approach having distinct advantages in ease of processing and cost. A typical example of this approach involves initial deposition of a thin, homogeneous metal layer (by any of the above-mentioned techniques) onto a substrate, followed by lithographic patterning of a resist to block selected regions of the underlying metal film. The exposed metal underlayer serves as either an electrode for electrolytic 7 up-plating or as a catalytic region for EL metal deposition. 8 However, even with these approaches, the initial thin metal layer can lead to significant problems in the ultimate device structures, and subtractive steps must again be used to remove the buried metal. We therefore sought to develop an alternative process utilizing photolithography and molecular self-assembly together to spatially control the binding of a Pd EL catalyst to a substrate and initiate EL metal deposition in a fully additive manner.We have previously shown that self-assembled (SA) films of organosilanes containing ligand functional groups such as phosphines, pyridines, or alkylamines are useful for binding Pd catalysts to surfaces and that the bound catalysts initiate EL deposition. 9-12 These films are formed by chemisorption of alkoxysilane or chlorosilane precursors (typically of formula R n SiX 4Ϫn , where R contains the ligating group, X ϭ Cl, OCH 3 , or OC 2 H 5 , and n ϭ 1-3) to hydroxyl groups on the surface of various substrates...

A new Pd(II) electroless metal deposition catalyst dispersion, PD2, prepared by quenching a PdCl solution with HC1 and excess NaC1 following rapid hydrolysis at pH -7 and -0.8 mM NaCl is described. The precursors to the catalytic Pd(0) species are shown to be chloride-rich Pd(II) colloidal particles having negative surface charge by x-ray photoelectron spectroscopy, UV-visible spectroscopy, centrifugation, and chemical tests. The particles bind selectively and covalently at ligand-modified surfaces with complete surface coverage occurring for treatment times 2 mm. Atomic force microscopy indicates that the average and maximum sizes of the bound particles are 9 3 and 18 nm, respectively. A correspondingly narrow distribution (15 to 33 nm) of Ni particles of average size 21 5 nm is obtained following metallization of catalyzed surfaces. The ability to control Ni particle morphology using PD2 is successfully exploited in the selective metallization of 15 nm features patterned by scanning tunneling microscopy. Metallization occurs with minimal distortion of feature geometries and no pattern degradation due to Ni overgrowth or bridging of adjacent features.Catalyst behavior is well described by a model in which domination of particle nucleation events and dispersion medium chemistry during colloid formation determine particle surface binding, stability, size, and dispersity. IntroduclionElectroless (EL) metal deposition is an autocatalytic,

A method for measuring acid generation efficiency is presented and utilized to determine the relative efficiency of four photoacid generators (PAGs) upon radiation with photon, electron, and ion beams. In this method, chemically amplified resists are prepared with varying amounts of base, coated into thin films (1000 AA), and exposed. Linear plots of the base concentration against the threshold exposure dose for each resist yield the threshold acid concentration and the acid generation rate constant for each PAG. The acid-generating efficiency of the four PAGs (ND-Tf, TPS-Tf, TBI-PFOS, and TBI-Tf) upon irradiation with DUV (248 nm), EUV (13.4 nm), X-ray (1 nm), e beam (30 and 50 keV), and He+ ions is evaluated

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