Making use of SPER (Solid Phase Epitaxial Regrowth) As and B deep source/drain junctions with high activation can be obtained at temperatures below 700°C. However, higher thermal budget is required to regrow and activate the dopants in the poly gates. Low junction leakage and low contact resistance can be obtained for Ni-silicided As and B SPER junctions making use of deep As and B implants. Because of the low thermal budget source/drain junctions obtained by SPER are an attractive alternative to conventional spike annealed junctions for technologies making use of metal gates.

A range of “single source” Sr-Nb and Sr-Ta heterometal alkoxides precursors are investigated as potential sources for liquid injection MOCVD (metalorganic chemical vapour deposition) and ALD (atomic layer deposition) of SrBi2Ta2O9 (SBT) and SrBi2(TxNb1-x)2O9 (SBTN). These “single source” precursors are designed to alleviate the mis-match between conventional Sr and Ta or Sr and Nb sources. Strontium-tantalate and strontium-niobate thin films were deposited on silicon using the “single source” alkoxide precursors [Sr{Ta(OEt)5(dmae}2] and [Sr{Nb(OEt)5(dmae)}2] (dmae = OCH2CH2NMe2), and the optimum temperatures for deposition of stoichiometric SrTa2O6 and SrNb2O6 were determined. Separate ALD studies of [Sr{Ta(OEt)5(dmae)}2] and [Sr{Ta(OEt)5(mee)}2] (mee = OCH2CH2OMe) for the growth of strontium-tantalate were carried out to assess precursor suitability for this technique. Liquid injection MOCVD of Bi-oxide films using Bi(mmp)3 indicates similar decomposition behaviour to the Sr-Ta and Sr-Nb alkoxides, demonstrating its suitability as a complementary source of Bi for SBT, SBN and SBTN.

More than 20 examples of probable prehistoric water basins with minimum storage capacities of 10,000–25,000 gallons of water are known in the Mesa Verde region of the American Southwest. The temporal placement of these artificially constructed basins, their exact uses, and their importance as public architecture have been poorly understood. We summarize the general literature on these features, give a detailed account of the excavation results of a dam and basin that we tested and dated, and then synthesize all available data from the gray literature on prehistoric water basins in our area. We argue that water basins and reservoirs in the northern Southwest typically stored domestic water for particular communities and that the first evidence of these public features is probably associated with Chaco-era communities. These features represent early experiments with large-scale water conservation and suggest a long-term commitment to locales by specific communities. Their locations along the canyon edges foreshadow shifts in settlement and increased water conservation strategies that become more pronounced in the later Great Pueblo-period villages-the last villages in this area before the migration of Puebloan people to the south after A.D. 1280.

As part of an ongoing investigation to characterize the properties and structure of zinc halide-tellurium oxide glasses, we report preliminary measurements of the optical properties of several Nd- and Er-doped tellurites. Measurements include florescence lifetimes and estimates of the theoretical radiative lifetimes (as obtained by traditional Judd-Ofelt analysis of optical absorption spectra) as well as phonon sideband studies sensitive to vibrational characteristics near the rare earth ion. The response of these optical features to the substitution of alternative halides is examined.

A week before the Reagan-Gorbachev summit in Washington, a group of American and Soviet scholars met in Moscow to explore how a new spirit of cooperation could be applied in Africa. The challenge was to find ways of transforming the well-established pattern of hostile competition between the two countries in that area of the world into one of collaboration for the mutual benefit of both countries and Africa. The results of the Moscow workshop are highly promising.