We show how cross-sectional scanning tunneling microscopy may be used to reconstruct the Sb segregation profiles in GaInSb /InAs strained-layer superlattices. These profiles are accurately described by a one-dimensional model parametrizing the spatial evolution of an Sb seed at the InAs-on-GaInSb interface in terms of two-anion-layer exchange. We argue that the segregation seed, which decreases from 2 / 3 to 1 / 2 monolayer when growth conditions are made less anion rich, has its origin in the Sb-bilayer reconstruction maintained during GaInSb epitaxy.

Two different approaches, a photoconductive response technique and a correlation of lasing thresholds with theoretical threshold carrier concentrations have been used to determine Auger lifetimes in InAs/GaInSb quantum wells. For energy gaps corresponding to 3.1–4.8 μm, the room-temperature Auger coefficients for seven different samples are found to be nearly an order-of-magnitude lower than typical type-I results for the same wavelength. The data imply that at this temperature, the Auger rate is relatively insensitive to details of the band structure.

Medical educators must acknowledge students' reasoning in professionally challenging situations and guide students to balance considerations of principles, implications, affects and cultural norms. The prominence of Confucian relationalism in this study, exhibited by students' considerations of the rippling effects of their behaviours on all their social relationships, calls for further cross-cultural studies on medical professionalism to move the field beyond a Western individualist focus.

An electrochemical deposition process for copper ͑Cu͒ metallization has been developed and investigated by the integration of nanoscaled palladium ͑Pd͒ catalyzation, electroless plating of Cu seed layers, and electroplating of Cu films in this study. Following surface cleaning and etching, sensitization and activation of Si/SiO 2 /TaN substrates were performed to obtain uniformly distributed Pd catalysts of only about 10 nm. Smooth and continuous 30 nm thick Cu seed layers with low electrical resistivity were electrolessly deposited using the nanosized Pd catalysts as nucleation sites. Copper metallization with high purity, small surface roughness, low electrical resistivity of 1.77 ⍀ cm, low residual stresses, and good adhesion to substrates was achieved using the subsequent electroplating on the electroless seed layers and postannealing. Good gap-filling capability on finely patterned structures was performed and exhibited the great application potential of low-temperature integrated electrochemical deposition process for next-generation Cu metallization of ultralarge-scale integrated circuits.As the packing density of semiconductor devices drastically increases, multilevel interconnection has been applied to compromise the insufficient surface area on integrated circuit ͑IC͒ chips. At the same time, the reduction in metal linewidths and pitches results in the rise of interconnect resistance and parasitic capacitance, leading to serious resistance-capacitance ͑RC͒ delay. 1,2 The RC delay has many drawbacks, especially the problem of low signal transmission speed, becoming the most difficult issue to overcome. Copper with lower electrical resistivity, high thermal conductivity, good mechanical properties, and high migration resistance has been used as interconnect metallization in dual-damascene structures of ultralargescale integrated ͑ULSI͒ circuits to replace aluminum and to directly reduce the metal line resistance. [3][4][5] Copper metallization technology mainly includes traditional ULSI techniques such as physical vapor deposition ͑PVD͒ and chemical vapor deposition ͑CVD͒, or newly developed electrochemical deposition including electroplating and electroless plating. 6-23 The PVD method provides precise composition control but presents poor step coverage in deep submicrometer dimension features, resulting in problems like overhangs or voids. 6-8 Though CVD has better step coverage, its development is also limited because high processing temperatures and expensive equipment are required in addition to the combustible and toxic precursors. 9,10 Electroplating has the advantages of low processing temperature, low cost, high throughput, and good film quality, and thus becomes more attractive. 3,11-15 However, due to the need of sputtered Cu seed layers for electroplating, this deposition technique is inadequate for next-generation metallization below 90 nm. Recently, the deposition of uniform Cu seed layers only 20 nm thick into trenches or vias with good sidewall step coverage and a high aspect ratio of 10 h...

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