Abstract: A method for chemical vapor deposition of a film comprising tantalum onto a substrate includes introducing into a deposition chamber: (i) a substrate; (ii) a source precursor in the vapor state; and (iii) at least one carrier gas, and maintaining the temperature of the substrate within the chamber as from about 70.degree. C. to about 675.degree. C. for a period of time sufficient to deposit a film comprising tantalum on the substrate. The source precursor has a formula (I):Ta(I.sub.5-m-n-p)(Br.sub.m- p)(Cl.sub.n- p)(R.sub.p) (I)wherein m is an integer from 0 to 5, n is an integer from 0 to 4, p is an integer from 0 to 4, and R is selected from the group consisting of hydrogen, and lower alkyl.

Abstract: A branched alkylsilane includes a branched hydrocarbon backbone which has a linear or branched alkylsilyl moiety extending asymmetrically from the backbone such that the backbone has a first portion and a second portion extending from the moiety. The second portion has two carbon atoms more than the first portion, and the alkylsilyl moiety includes at least one hydrolyzable group bound to silicon for reacting with a substrate. A method for preparing a branched alkylsilane useful for chromatographic applications includes the steps of preparing a vinylidene olefin by dimerization of an .alpha.-olefin and reacting it with a monomeric silane having a silicon-hydrogen bond in the presence of a metallic catalyst such that the silicon-hydrogen bond is added to the vinylidene double bond of the vinylidene olefin thereby converting the double bond to a single bond and bonding the silicon of the monomeric silane to the vinylidene olefin to form a branched alkylsilane.

Abstract: Silsesquioxane polymers that are useful for preparing SiO.sub.2 -rich ceramic coatings are obtained as the polymeric reaction products from the hydrolysis and condensation of organosilanes having a .beta.-substituted alkyl group. A preferred silsesquioxane polymer is the polymeric reaction product obtained from .beta.-chloroethyltrichlorosilane. Coating compositions containing such silsesquioxane polymers dissolved in organic solvent may be applied to a substrate and converted to SiO.sub.2 -rich ceramic thin layers by evaporating the solvent and heating the coated substrate at moderate temperatures.

Abstract: Novel hydroxymethyltrialkoxysilanes of the formula: ##STR1## are produced by transesterifying a carboxylic acid ester of hydroxymethyltrialkoxysilane with an alcohol, and distilling the reaction mixture to remove the carboxylate of the alcohol. The carboxylic acid ester of hydroxymethyltrialkoxysilane is prepared by the reaction of an alkali metal carboxylate with chloromethyltrialkoxysilane, which in turn is prepared by the reaction of a trialkylorthoester with chloromethyltrichlorosilane by heating to reflux with removal of alkylchloride, followed by distillation to remove alkyl ester. The hydroxymethyltrialkoxysilanes and carboxylic acid esters thereof, as well as carboxymethyltrialkoxysilanes, are particularly useful in sol-gel processing by undergoing hydrolysis to yield hydroxymethylsilanetriol, and subsequent hydrolysis and polycondensation products.