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Realizing environmentally benign silicon-wafer cleaning has become one of the most important topics in the semiconductor industry. We have developed an ultra-diluted HF/nitrogen-gas jet spray procedure for single-wafer spin cleaning, which can efficiently remove not only particulate but also metallic contaminants in 20 s from both silicon and silicon-dioxide surfaces without causing damage to fragile 45-nm wide polycrystalline-silicon gate structures. The use of a very low HF concentration makes the silicon and oxide losses negligible, below 0.003 and 0.03 nm, respectively. This simple, single-step, single-wafer Spin CLeaning with use of Ultra-Diluted HF/nitrogen jet spray (SCLUD) drastically reduces the chemical and water consumption as well as electrical energy per wafer due to the short spraying time with the ultra-diluted HF at room temperature. HF wastewater, the only effluent of this cleaning, is recycled by forming Ca[F.sub.2], which can be a raw material for HF or Portland cement. This cleaning, therefore, meets the requirements with respect to the environmental control. Index Terms--Jet spray, RCA cleaning, single-wafer spin cleaning with repetitive use of ozonated water and diluted HF (SCROD), single-wafer spin cleaning, single-wafer spin cleaning with use of ultra-diluted HF/nitrogen jet spray (SCLUD).

As semiconductor devices continue to get smaller, and thus the size of yield-limiting particles decreases, a need has arisen for detecting smaller particles on silicon surfaces. The current minimum detectable diameter of wafer-surface particle-detection systems employing 488-nm wavelength [Ar.sup.+] gas lasers widely used in semiconductor production lines is, under optimized conditions, 50-60 nm on bulk-silicon surfaces. The sensitivity for SOI wafers, however, is considerably lower than this level due not only to the additional optical reflections from Si/Si[O.sub.2]/Si interfaces within the SOI stack but also to the undesirable light scattering at the rough interfaces. The challenges in meeting the requirement to detect smaller particles specified in the ITRS will be presented. Using a 266-nm solid-state laser, we have developed for semiconductor manufacturing a high sensitivity system capable of detecting particles as small as 30 and 40 nm on unpatterned bulk-silicon wafers and SOI wafers, respectively. Our technique of single-wafer spin cleaning with repetitive use of ozonated water and dilute HF cleaning of silicon wafers can reduce surface microroughness, thus reducing background noise in this system, and providing higher particle-detection sensitivity than conventional RCA cleaning. Defect classification using this system integrated with a review scanning electron microscope will also be discussed. Index Terms--Laser applications, optical scattering, particle measurements, particle sources, silicon on insulator (SOI), SIMOX, surface contamination.

The azathiolation of carbon monoxide using S-phenyl-N-diethylsulfenamide and palladium as the catalyst is described. The S-N bond makes the sulfenamide a very efficient substrate in transition-metal-catalyzed reactions.

The reaction of propargylic alcohols with diaryl disulfides and carbon monoxide in the presence of tetrakis(triphenylphosphine)palladium results into a novel thiolative lactonization to produce beta-(arylthio)-alpha,beta-unsaturated lactones in moderate to good yields. Similar conditions can be used with homopropargylic alcohols, providing the corresponding delta-lactones with a beta-arylthio group. The reaction employing diaryl diselenides instead of diaryl disulfides also leads to a similar one-pot thiolation/lactonization sequence to produce the corresponding beta-selenobutenolides.

The catalytic and stoichoimetric behavior of isocyanide and thiolate ligands on palladium and platinum demonstrating as the first evidence of insertion of isocyanide into a metal-sulfur bond was presented. Data indicated that the insertion of isocyanide into the Pd-S bond can be reversible and that the relative stability of the oxidation state of the complexes determine the reactivity of the isocyanide and thiolate bonds with palladium and platinum compounds.

Pt[(P[Ph.sub.3]).sub.4] has catalyzed intramolecular vinylthiolation and -selenation of internal alkynes with vinyl chalcogenides having a carbamoyl group on the cis-[beta]-position of the vinyl moiety, thus giving rise to the highly conjugated [delta]-lactam frameworks. The alkyne insertion processes has shown that the formation of seven-membered platinacycle is kinetically favored and the introduction of electron withdrawing groups to [beta]-position on vinyl moiety is vital for developing new type of catalytic reaction by using vinyl heteroatom compounds.

Pd catalyzes intramolecular selenocarbamoylation of alkynes is discovered to give alpha-alkylidenelactams. The possibility of selenocarbamoylation is examined by reacting a carbamoselenoate, PhSe-C(O)-NMe2, with an alkyne.

The first example of a metal-catalyzed cross-coupling reaction of alkyl fluorides with Grignard reagents is revealed. The reactions proceed efficiently between primary alkyl fluorides and various Grignard reagents under mild conditions in the presence of nickel or copper salts.

Rotational-echo double resonance (REDOR) is used for determining heteronuclear distances. The (super 15)N-detected C-H REDOR experiment could be applied routinely whenever (super 13)C-(super 15)N REDOR is used to characterize a biomolecular structure, which promises to provide useful information on CO-H(super N) hydrogen bonding.

A topological, noncovalent solution to improving the dispersion of single-walled carbon nanotubes (SWNTs) is demonstrated by encasing them in cross-linkable surfactant micelles. Micelle-encapsulated SWNTs are compatible with a wide variety of solvent and polymer matrices, hence-SWNTs could be used as an alternative starting material to pure SWNTs for the production and investigation of nanotube composite materials.

The trans insertion of phenylacetylene into the H-Pt bonds that took place with the assistance of unexpected factors is reported. The participation of trans insertion (IS) in Pt-catalyzed reactions is under investigation.

Research has been conducted on Grignard reagents. The reaction of these reagents with alkyl halides, tosylates and bromides carried out via nickel catalyst addition is described.

Iron-catalyzed cross-coupling reaction of vinylic ethers with aryl Grignard reagents is described. The reaction proceeded at room temperature with catalytic amounts of an iron salt without the aid of costly ligands and additives. In this catalytic system, vinylic C−O bonds were preferentially cleaved over aromatic C−O bonds of aryl ethers or aryl sulfonates. [ABSTRACT FROM AUTHOR]

A transition-metal-catalyzed carbothiolation of alkyne prototype is reported.