Abstract: Scavenger compositions useful for purifying process gas streams, such as process gas streams, such as hydrogen, nitrogen, noble gases, diborane, and hydride gases from Groups IVA-VIA of the Periodic Table, such as arsine, phosphine, silane, germane, hydrogen selenide, and hydrogen telluride, and mixtures thereof, to remove water, oxygen, and other oxidant and Lewis acid impurities therefrom, such scavenger comprising a porous, high surface area inert support having thereon an active scavenging species, formed by the deposition on the support of a Group IA metal and pyrolysis thereof at a selected elevated temperature on said support.

Abstract: An in-line detector system for real-time detection of impurity concentration in a flowing gas stream. In a specific aspect, the system may comprise a purifier unit for selective purification of gas from the gas stream, and an impurity addition unit for imparting a predetermined concentration of impurity to the gas stream, whereby the resulting concentration sensings of the purified gas, and the impurity-enhanced gas are usefully employed to calibrate an impurity concentration sensor, for continuous accurate sensing of impurity concentration in the flowing gas stream. The system may utilize hygrometric sensors in the case of water as a critical impurity, or surface acoustical wave (SAW) devices coated with suitable impurity-affinity coatings. The system has particular utility in monitoring low impurity concentration levels (e.g., from about 0.1 ppm to about 100 ppm) in gas streams employed in vapor-phase processes such as chemical vapor deposition in the manufacture of semiconductor devices.

Abstract: A method for cleaning an exhaust gas containing ammonia and at least one silicon-containing compound selected from the group consisting of silane and chlorosilanes, which comprises contacting the exhaust gas with a scavenger comprising a metal salt which forms tight complexes with ammonia. This ammine-forming metal salt may be immobilized on a porous solid support. Suitable ammine-forming metal salts include the sulfates, nitrates, chlorides, bromides, iodides, and hydroxides of copper, cobalt, iron, and nickel. Suitable supports include materials which are compatible with the gas mixtures being cleaned and the reaction products of the sorption process and which are stable under the conditions of use. Useful support materials include zeolites, aluminosilicates, alumina, silica, silica gel, kieselguhr, and activated carbon.

Abstract: An endpoint detector for gas purifiers which contains a detection element comprising a small amount of a highly reactive metal coated on an insulator and exposed to the gas stream being purified. This metal does not react with the gas being purified, but does undergo reaction with the impurity species. As this metal reacts with impurities in the gas stream, its conductivity decreases. The change in conductivity signals that the wave front of impurity-containing gas has reached the sensor, and thus the purifier has reached the end of its useful life. The use of a thin coating of reactive metal as the detection element gives the sensitivity that is required to sense sub-part-per-million levels of impurities. This resistance change sensor may be combined with a thermal measurement to detect the presence of exothermic conditions indicative of a large pulse of impurity gas.

Abstract: A sorbent composition comprising a first sorbent bed of hygroscopic aluminosilicate sorbent and a second sorbent bed comprising an aluminosilicate sorbent impregnated with an aqueous base solution, whereby the hygroscopic aluminosilicate sorbent provides an initial contact zone to protect upstream gas and processing equipment from reaction products resulting from back-diffusion of water which will occur in the absence of the first sorbent.

Abstract: An in-line detector system for real-time detection of impurity concentration in a flowing gas stream in which purified and unpurified volumes of gas from the flowing gas stream are subjected to concentration sensing, to determine a corrected impurity concentration value for the flowing gas stream. The system in a preferred embodiment employs a manifold in flow communication with a purifier unit, a main flow conduit through which the flowing gas stream is passed, and a sensor port, with a selectively positionable valve to flow gas through a purifier loop of the manifold to the sensing port, and alternately through a bypass loop of the manifold without passage through the purifier unit, for comparative impurity sensing of gas in the respective loops. The system may utilize hygrometric sensors in the case of water as a critical impurity, or surface acoustical wave (SAW) devices coated with suitable impurity-affinity coatings. The system has particular utility in monitoring low impurity concentration levels (e.g.

Abstract: A scavenger composition having utility for removal of water and silicon mu-oxide impurities from chlorosilanes, such scavenger composition comprising:(a) a support; and(b) associated with the support, one or more compound(s) selected from the group consisting of compounds of the formula:R.sub.a-x MCl.sub.xwherein:M is a metal selected from the group consisting of the monovalent metals lithium, sodium, and potassium; the divalent metals magnesium, strontium, barium, and calcium; and the trivalent metal aluminum;R is alkyl;a is a number equal to the valency of metal M; andx is a number having a value of from 0 to a, inclusive; andwherein said compound(s) of the formula R.sub.a-x MCl.sub.x have been activated for impurity-removal service by a reaction scheme selected from those of the group consisting of:(i) reaction of such compound(s) with hydrogen chloride to form a first reaction product therefrom, followed by reaction of the first reaction product with a chlorosilane of the formula:SiH.sub.4-y Cl.sub.

Abstract: A scavenger composition having utility for removal of water and silicon mu-oxide impurities from chlorosilanes, such scavenger composition comprising:(a) a support; and(b) associated with the support, one or more compound(s) selected from the group consisting of compounds of the formula:R.sub.a-x MCl.sub.xwherein:M is a metal selected from the group consisting of the monovalent metals lithium, sodium, and potassium; the divalent metals magnesium, strontium, barium, and calcium; and the trivalent metal aluminum;R is alkyl;a is a number equal to the valency of metal M; andx is a number having a value from 0 to a, inclusive; andwherein said compound(s) of the formula R.sub.a-x MCl.sub.x have been activated for impurity-removal service by a reaction scheme selected from those of the group consisting of:(i) reaction of such compound(s) with hydrogen chloride to form a first reaction product therefrom, followed by reaction of the first reaction product with a chlorosilane of the formula:SiH.sub.4"y Cl.sub.