Laser irradiation of organometallic palladium compounds with an argon ion laser at 351 nm is used to selectively deposit catalytic amounts of palladium on polyimide. Subsequent immersion of the irradiated samples in an electroless copper solution results in copper deposition. Since a few monolayers of palladium are sufficient to catalyze the electroless copper process, fast writing speeds of several centimeters per second are obtained.

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This paper describes a novel excimer laser beam delivery method for surface sculpting using a binary mask approach. This technique is useful for profiling a surface into arbitrary shapes and geometries with a high laser energy delivery efficiency. The binary mask technique is particularly attractive for deliver of a pulsed laser such as excimer lasers which are normally operated at a relatively low repetition rate but their output energies per pulse are high. This paper discusses the principle and the method of using the binary masks to regulate the laser energy distribution. An example is given in which a set of 8 binary masks, each has 1 00 by 1 00 pixels over an area of 5mm in diameter, is used for flattening the curvature of a spherical surface.

Copper/polyimide (Cu/PI) structures are used extensively for computer packaging applications. For high circuit density multi-chip substrates, a thin film (typically 2-5μm) of polyimide is used; but the polyimide used to interconnect the multi-chip substrates via tape automated bonding (TAB) is typically 50μm thick to protect the tape leads from the cantilever effect. Although many spectroscopic, adhesion and deformation studies have been published about the bonding of metals to thin polyimide, relatively little has been published regarding the use of metal on thick polyimide.One factor limiting the analyses of these interfaces derived from the thick polyimide is the difficulty preparing adequate TEM specimens.Due to the greatly differing ion milling rates of metals and polymers, and the thickness of the two layers, a preparation technique was developed on model tape samples.The model samples consisted of 1μm sputtered Cu on 50μm polyimide, with and without Cr adhesion layers.