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When I was in graduate school in 1979 studying electorochemical engineering at Berkeley, Joan Berkowitz was the ECS President. It never crossed my mind that this was unusual - it seemed about right that a woman was in charge once in awhile. From that starting inspiration 40 years ago, I have enjoyed a long and interesting career (from electrochemistry to software product development), and also raised three daughters (who are themselves scientists and journalists, and still the sparkling joy of my life). In this talk, I will describe some of my professional experiences, my evolution as an inventor, some early volunteer work for the the ECS, some interesting sidetracks. I’ll reflect on how to define a career so it can be balanced with competing passions.

Cellular data from call detail records can help urban planners better understand city dynamics. The authors use CDR data to analyze people flow in and out of a suburban city near New York City.

The use of hot water immersion to aid in the drying of wafers subsequent to liquid chemical processing has recently been increasing. Both the TREBOR Hydrodry™ and the Isopropyl Alcohol (JPA) dry used by CFM Technologies Inc. use water rinses at elevated temperature. These treatments are of particular concern when they follow HF immersions where surface oxides are removed and bare silicon surfaces are exposed to the hot water. Studies by Watanabe et al.{sp1} show that Si(111) facets can be produced by hot water immersion. This, in turn, implies that hot water etches silicon with an anisotropic etch rate. In this work, the etching of oxide patterned Si(100) wafers by immersion in hot water is studied. Etching is clearly observed in images produced by Transmission Electron Microscopy (TEM) with a concomitant increase in surface roughness. The rate of etching varies dramatically with the dissolved oxygen concentration of the water used. Possible mechanisms to explain the etching will be discussed.

We have used in situ scanning tunneling microscopy to examine submonolayer Cu deposition from a sulfuric acid electrolyte on Au(111), sampling over large areas of the surface. We describe the growth of three distinct superlattice phases of Cu on the Au(111) surface before the onset of bulk deposition of Cu. In the earliest stages of deposition, during an electrochemical current peak, we observe the rapid growth of a low height phase, with an apparent height of 0.46±0.10 A. During this time, a second, monolayer‐height phase forms as small islands. We identify these phases as the (√3×√3)R30° and (1×1) Cu superlattices, respectively. A third phase appears at about 175 mV (versus Cu/Cu+2), and grows from nucleation points at the top edges of atomic steps and around the small (1×1) Cu islands. This phase, which we believe is a (5×5) Cu adlayer, slowly supplants the (√3×√3)R30° layer.

We find that a Au(111) electrode is substantially roughened after a single monolayer of Pb is electro-plated and stripped from the surface in a linear sweep experiment. The roughened electrode surface rearranges into 20 to 150 A diamter islands which are one atomic layer high, and separated by 20 to 50 A. This process is observed on all samples, for sweep rates ranging from 0.5 to 1000 mV/s. If a partial layer of Pb is plated and then stripped, pitting and an increased overpotential for Pb deposition are observed only in the areas adjacent to the plated sites. We suggest that these observations are consistent with the formation of a PbAu alloy in the surface layer.

A system and methodology for managing a mute function muting a connection to a conference call is disclosed. The system is implemented when the mute function is activated on a line connected to a conference call through a telecommunications network. The method includes receiving a sound, determining whether the sound meets predetermined criteria and if the sound meets predetermined criteria then performing a mute status operation.

A technique commonly used as the final stage of cleaning gold electrode surfaces is to electrochemically form and reduce a monolayer of oxide on the surface. We have investigated the changes on the Au(111) surface during this procedure using in situ electrochemical scanning tunneling microscopy.

The electrochemistry of iodide in propylene carbonate (PC) was investigated using cyclic voltammetry. In an anodic sweep, iodide is oxidized sequentially to triiodide and then to iodine according to 3I/sup -/ ..-->.. I/sub 3//sup -/ + 2e/sup -/ (I) 2I/sub 3//sup -/ ..-->.. 3I/sub 2/ + 2e/sup -/ (II). This mechanism was confirmed using UV-visible spectroscopy in conjunction with cyclic voltammetry experiments at a thin gold mesh electrode. Potential step experiments were used to measure a diffusion coefficient of 4 X 10/sup -6/ cm/sup 2//s for iodide in a KAsF/sub 6/ PC electrolyte.

An algorithm based on Duhamel's superposition integral is used to simulate cyclic voltammograms for iodide electro-chemistry on platinum in propylene carbonate. The electrochemistry is represented by the reaction sequence 3I/sup -/ ..-->.. I/sub 3//sup -/ + 2e/sup -/ (I) 2I/sub 3//sup -/ ..-->.. numberI/sub 2/ + 2e/sup -/ (II) where reaction (I) is rate limited (Butler-Volmer kinetics) and reaction (II) is reversible (Nernst equilibrium behavior). Since the nonunity stoichiometries and Butler-Volmer kinetics in the reaction sequence prohibit the use of analytical solution techniques, the superposition-integral algorithm is used as a fast and accurate method for the numerical simulation. The simulated voltammograms for the iodide system agree very well with experimental observations and support the proposed reaction sequence.

A cell to permit in-situ imaging of the electrodeposition of silver on gold from a polymer electrolyte by TEM is described. The extremely thin electrochemical cells were composed of a layer of polyethylene oxide containing a silver salt between evaporated silver and gold electrodes. Observations from preliminary in-situ TEM experiments include the nucleation and growth, and coalescence of silver islands oriented epitaxially to the gold electrode.