The invention provides a facile process for preparing various Group VI precursor compounds useful in the vapor deposition of such Group VI metals onto solid substrates, especially microelectronic semiconductor device substrates. The process provides an effective means to obtain such volatile materials, which can then be sources of molybdenum, chromium, or tungsten-containing materials to be deposited on such substrates. Additionally, the invention provides a method for vapor deposition of such compounds onto microelectronic device substrates.

Some embodiments relate to precursors (including intermediate precursors) and related methods. To prepare an intermediate precursor, a mixture of bis (arene) metal complexes is combined with a first arene. The mixture of bis (arene) metal complexes and the first arene are heated and subsequently cooled. Upon cooling, a bis (first arene) metal complex precipitates from solution to obtain an intermediate precursor with high purity. To prepare a precursor, the bis (first arene) metal complex is contacted with a second arene and heated to obtain a precursor with high purity.

The invention relates to a solid catalyst system comprising a chromium compound, a metal compound, an aluminium compound and a silicon oxide support, wherein the silicon oxide support has an average particle diameter in the range between ≥20 and ≤50 μm, a pore volume in the range between ≥1.7 ml/g and ≤3 ml/g, and a surface area in the range between ≥400 m.sup.2/g and ≤800 m.sup.2/g, and wherein the aluminium alkoxide compound has the formula
R.sub.1—Al—OR.sub.2
wherein R.sub.1 is selected from (C.sub.1-C.sub.8) alkyl groups and OR.sub.2 is selected from (C.sub.1-C.sub.8) alkoxyl groups.

Disclosed are molybdenum-containing complexes used in compositions and methods for inhibiting or reducing the deposition of foulant on equipment.

Disclosed are molybdenum-containing complexes used in compositions and methods for inhibiting or reducing high temperature corrosion in petroleum refineries.

The present invention relates to a ligand, an ethylene oligomerization catalyst including the ligand, and a method for selectively producing 1-hexene or 1-octene from ethylene by using the catalyst. The ligand according to the present invention is a bis(diphenylphosphino)ethene with a phosphorus atom substituted with a fluoro-substituted phenyl, and when the ligand is used for ethylene oligomerization, the high temperature activity of the catalyst can be increased.

There is a process for preparing polycarbonate. The process has the step of copolymerizing an epoxy compound and carbon dioxide (CO.sub.2) in the presence of a catalytic system having at least one catalyst selected from complexes of a transition metal having general formula (I):

##STR00001##

The aforesaid process allows to obtain polycarbonates having a quantity of carbonate bonds in chain greater than 95% or polycarbonate/polyether copolymers having a quantity of ether bonds in chain ranging from 15% to 90%.

The present invention provides a metal-oxo complex represented by the following general formula (1),

##STR00001## wherein in the general formula (1) above, “M” represents a molybdenum atom or a tungsten atom; “A” represents a carbon atom, a silicon atom, a germanium atom, a tin atom or a lead atom; X.sup.1 and X.sup.2 each independently represent a halogen atom; R.sup.1 to R.sup.5 each independently represent a hydrogen atom, a straight or branched chain alkyl group that is substituted or unsubstituted and has 1 to 20 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 20 carbon atoms; each of R.sup.1 to R.sup.3 may be bonded to one another to form a ring.

The invention provides a facile process for preparing various Group VI precursor compounds, set forth below as Formula (I), useful in the vapor deposition of certain Group VI metals onto solid substrates, especially microelectronic semiconductor device substrates. Also provided is a process for the preparation of such precursor compounds. Additionally, the invention provides a method for vapor deposition of Group VI metals onto microelectronic device substrates utilizing the precursor compounds of the invention.

Atomic layer deposition (ALD) processes for forming Te-containing thin films, such as Sb—Te, Ge—Te, Ge—Sb—Te, Bi—Te, and Zn—Te thin films are provided. ALD processes are also provided for forming Se—containing thin films, such as Sb—Se, Ge—Se, Ge—Sb—Se, Bi—Se, and Zn—Se thin films are also provided. Te and Se precursors of the formula (Te,Se)(SiR.sup.1R.sup.2R.sup.3).sub.2 are preferably used, wherein R.sup.1, R.sup.2, and R.sup.3 are alkyl groups. Methods are also provided for synthesizing these Te and Se precursors. Methods are also provided for using the Te and Se thin films in phase change memory devices.