The spatial profiles of hot-carrier-induced interface traps in MOSFET's with abrupt arsenic junctions and oxide thicknesses of 10-38 nm are determined using change pumping both in the conventional manner and with a modified "constant field" approach. For the thinnest oxides we find the damage to he highly localized in a very sharp peak that is located inside the drain at the point of maximum lateral electric field. In thicker oxides, the damage peak is broader and is shifted toward the edge of the drain junction. Two-dimensional device simulations using the measured profiles are in qualitative agreement with measured I-V characteristics after degradation. However, the magnitude of the predicted degradation is underestimated, suggesting that significant electron trapping occurs also.

Analysis of thickness vs. time data for oxides thermally grown on Si in dry oxygen reveals that deviations from the widely used linear parabolic rate law exist in the thick oxide regime as well as in the better‐known initial “fast” growth regime. We suggest two rate laws that eliminate these deviations without resorting to a special oxidation mechanism in either regime. One of these rate laws is phenomenological, and one is based on a physical model in which the oxygen flux through the growing oxide is considered to have two components. One component reflects the usual diffusion of oxygen, and is thickness dependent; another one is thickness independent and is attributed to transport through structural channels.

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There is growing interest in “customer-based corporate valuation”—that is, explicitly tying the value of a firm’s customer base to its overall financial valuation using publicly disclosed data. While much progress has been made in building a well-validated customer-based valuation model for contractual (or subscription-based) firms, there has been little progress for noncontractual firms. Noncontractual businesses have more complex transactional patterns because customer churn is not observed, and customer purchase timing and spend amounts are more irregular. Furthermore, publicly disclosed data are aggregated over time and across customers, are often censored, and may vary from firm to firm, making it harder to estimate models for customer acquisition, ordering, and spend per order. The authors develop a general customer-based valuation methodology for noncontractual firms that accounts for these issues. They apply this methodology to publicly disclosed data from e-commerce retailers Overstock.com and Wayfair, provide valuation point estimates and valuation intervals for the firms, and compare the unit economics of newly acquired customers.