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Iridium oxide films formed by electrodeposition onto noniridium metal substrates are compared with activated iridium oxide films (AIROFs) as a low impedance, high charge capacity coating for neural stimulation and recording electrodes. The electrodeposited iridium oxide films (EIROFs) were deposited on Au, Pt, PtIr, and 316 LVM stainless steel substrates from a solution of IrCl/sub 4/, oxalic acid, and K/sub 2/CO/sub 3/. A deposition protocol involving 50 potential sweeps at 50 mV/s between limits of 0.0 V and 0.55 V (versus Ag|AgCl) followed by potential pulsing between the same limits produced adherent films with a charge storage capacity of >25 mC/cm/sup 2/. Characterization by cyclic voltammetry and impedance spectroscopy revealed no differences in the electrochemical behavior of EIROF on non-Ir substrates and AIROF. The mechanical stability of the oxides was evaluated by ultrasonication in distilled water followed by dehydration and rehydration. Stability under charge injection was evaluated using 200 /spl mu/s, 5.9 A/cm/sup 2/ (1.2 mC/cm/sup 2/) cathodal pulses. Loss of iridium oxide charge capacity was comparable for AIROFs and the EIROFs, ranging from 1% to 8% of the capacity immediately after activation or deposition. The EIROFs were deposited and evaluated on silicon microprobe electrodes and on metallized polyimide electrodes being developed for neural recording and stimulation applications. [ABSTRACT FROM PUBLISHER]

The forces for high speed, high capacity data services are driving the next generation network architecture toward a packet network. These next generation networks are basically of two types: wired networks and wireless networks. Changes in network services, technology and regulation are creating a golden era of network innovation. Much is certain in this evolution. For instance, the networks will have a shared, packet-based, optical-core network using dense wavelength division multiplexing (DWDM) optical transport with optical add/drop and multiplexing. Wireless communications is expected to be a major driver for growth in the telecommunications industry over the next decade. It will become a cornerstone of the information society. Future networks (both wireless and wireline) of the type described here will pave the way for an environment in which information will be made more portable, personal and affordable. They will achieve the ultimate goal of communications-communications from anywhere to anywhere-clear as a bell [ABSTRACT FROM PUBLISHER]