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The adhesion of electrochemically deposited copper on top of chemically surface modified epoxy layers for buildup purposes is examined. Using a wet-chemical surface synthesis reaction iminodiacetic acid, imidazole, and mercaptopyrimidine groups were chemically imprinted on the surface of buildup epoxy layers based on nucleofilic substitutions. The synthesis was followed by an identical electroless Cu deposition and peel strength measurement sequence. The identity of certain groups at the surface has pronounced influence on the adhesion strength of electrochemically deposited metals and is compared with traditional swell/ oxidation treatments of the surface of the polymer. By varying the identity of the chemical groups at the surface, the chemical part of the adhesion can be altered. The changes in roughness of the polymer surface were minimized by choosing solvents that exhibit minimum diffusion into the polymer and by limiting the reaction temperature. In this way the changes in the physical part of adhesion could be kept to a minimum. The chemical composition of the surface is examined by attenuated total reflection-infrared and X-ray photoelectron spectroscopy measurements. Weight changes were recorded after each separate wet-chemical treatment. Surface synthesis influences the peel strength negatively or positively and modifies the deposition rate and etching speed of electrochemically deposited copper.The surface properties of the polymer obviously have a big impact on the adhesion strength of electrochemically deposited metals on epoxy polymers used for buildup purposes. By chemical treatment the characteristics ͑physical and chemical͒ of the polymer surface can be changed in order to improve adhesion. Hence there is intense recent research into improving the adhesion of plated copper onto polymer surfaces. A number of publications 1-6 exist on surface treatments with wet chemicals to improve adhesion strength of electrochemical deposited copper on polymers.The study of the mechanisms of adhesion uses various concepts, emphasized by the fact that many theoretical models of adhesion have been proposed. These theories are both complementary and contradictory. 7 The five theories used are mechanical interlocking, electronic theory, the theory of boundary layers and interfaces, adsorption ͑thermodynamic͒ theory, and chemical bonding theory. 7 All theories consider two parts of adhesion: The physical or mechanical part of adhesion, which is linked to the roughness of the interface, and the chemical part of adhesion, caused by the interactions between the materials of both layers.The mechanical interlocking theory, proposed originally by MacBain and Hopkins, 8 conceives of mechanical keying or interlocking of one substance into cavities, pores, and asperities of the other material to be the major factor in determining adhesive strength. However, the possibility of establishing a good adhesion between smooth surfaces leads to the conclusion that the theory of mechanical keying cannot be universal. To overcome this...

The micropatterning of a series new poly(carbonate‐urethanes) with IR and excimer lasers is discussed. A series of segmented polyurethanes consisting of a soft segment and a hard segment was prepared. The soft segment, a thermodegradable polycarbonate diol, degrades by a syn‐elimination at higher temperature. The hard segment was selected as to increase the sensitivity of the polymers for UV excimer laser ablation. The thermal and mechanical properties of the segmented polyurethanes (SPU) were investigated. By varying the building blocks in the polymer (soft and hard segments), the ablation properties were studied in terms of absorption coefficient and threshold value. Polymers with an aromatic chain‐extender and an diisocyanate showed the highest absorption coefficient at wavelengths of 248 and 193 nm. Irradiation of these polymers led to cavities with high dimensional quality, sharp edges and no accumulation of degradation products near the cavities (no debris formation). Ablation with an IR laser led to a decrease in film thickness of the polymer deposited on a substrate. This was investigated with FTIR/ATR analysis and atomic force microscopy. Debris formation was found near the cavities. The differentiation of polarity between the exposed and unexposed areas was not efficient enough to use them as a coating for printing plates. © 2002 Society of Chemical Industry

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Residual stresses in electrolyte copper-nickel compositionally modulated multilayers (CMM) deposited from sulfate plating solutions on low carbon steel substrates have been determined using a low incident beam angle x-ray diffraction technique. The sublayer thickness was varied from 0.1 to 1.5 txm, while the total thickness of the compositionally modulated multilayer was kept at 3 ~m. For reference, residual stress measurements were performed on electrolytic nickel deposited from Watts' nickel plating solutions. The evolution of the residual stresses in the compositionally modulated multilayers was measured as a function of the copper and nickel sublayer thicknesses. A general formula to calculate the x-ray information depth in CMMs was derived and used to obtain the residual stress depth profile in electrolytic coppernickel CMMs.