Abstract: A vacuum pumping system comprises a primary foreline for receiving a gas stream from an outlet of a chamber, a first vacuum pump for evacuating the chamber, a second vacuum pump for evacuating the chamber, a first secondary foreline for conveying gas from the primary foreline to the first vacuum pump, a second secondary foreline for conveying gas from the primary foreline to the second vacuum pump, and valve means for selectively connecting a chosen one of the first and second secondary forelines to the primary foreline. The condition of the vacuum pumps is monitored during use. When both vacuum pumps are operating normally, the valve means is controlled to divert a first reactant-rich gas from the primary foreline into the first secondary foreline, and to divert a second reactant-rich gas from the primary foreline to the second secondary foreline, thereby inhibiting mixing of the first and second reactants within the vacuum pumps.

Abstract: An apparatus includes a foreline for conveying a waste stream which is drawn from a process chamber to a pumping mechanism. The foreline comprises an isolation valve for selectively isolating the pumping mechanism from the process chamber and a bypass positioned around the isolation valve. The apparatus further comprises a controller for actuating the isolation valve. The controller is configured to cause the isolation valve to be closed when the waste stream is initially drawn from the process chamber, during which time the waste stream is conveyed to the pumping mechanism via the bypass. The bypass includes means for inhibiting propagation of a flame front therethrough. The controller is configured to cause the isolation valve to be opened once a pressure within a region upstream of the isolation valve has been reduced below a value at which propagation of a flame front within the waste stream can be sustained.

Abstract: Apparatus and a method are provided for inhibiting the propagation of a flame front that is ignited by a pumping mechanism which draws a waste stream from a process chamber. The apparatus comprises a foreline for conveying the waste stream which is drawn from the process chamber to the pumping mechanism. The foreline comprises an isolation valve for selectively isolating the pumping mechanism from the process chamber and a bypass positioned around the isolation valve. The apparatus further comprises a controller for actuating the isolation valve. The controller is configured to cause the isolation valve to be closed when the waste stream is initially drawn from the process chamber. During which time the waste stream is conveyed to the pumping mechanism via the bypass, the bypass comprises means for inhibiting propagation of a flame front therethrough.

Abstract: A method is described of treating a gas stream exhausted from an atomic layer deposition (ALD) process chamber to which two or more gaseous precursors are alternately supplied. Between the process chamber and a vacuum pump used to draw the gas stream from the chamber, the gas stream is conveyed to a gas mixing chamber, to which a reactant is supplied for reacting with one of the gaseous precursors to form solid material. The gas stream is then conveyed to a cyclone separator to separate solid material from the gas stream. By deliberately reacting a non-reacted precursor to form solid material upstream from the pump, reaction within the pump of the non-reacted precursor and a second non-reacted precursor subsequently drawn from the chamber by the pump can be inhibited.

Abstract: A method is described of treating a gas stream exhausted from an atomic layer deposition (ALD) process chamber to which two or more gaseous precursors are alternately supplied. Between the process chamber and a vacuum pump used to draw the gas stream from the chamber, the gas stream is conveyed to a gas mixing chamber, to which a reactant is supplied for reacting with one of the gaseous precursors to form solid material. The gas stream is then conveyed to a cyclone separator to separate solid material from the gas stream. By deliberately reacting a non-reacted precursor to form solid material upstream from the pump, reaction within the pump of the non-reacted precursor and a second non-reacted precursor subsequently drawn from the chamber by the pump can be inhibited.

Abstract: Apparatus and a method are provided for inhibiting the propagation of a flame front that is ignited by a pumping mechanism which draws a waste stream from a process chamber. The apparatus comprises a foreline for conveying the waste stream which is drawn from the process chamber to the pumping mechanism. The foreline comprises an isolation valve for selectively isolating the pumping mechanism from the process chamber and a bypass positioned around the isolation valve. The apparatus further comprises a controller for actuating the isolation valve. The controller is configured to cause the isolation valve to be closed when the waste stream is initially drawn from the process chamber. During which time the waste stream is conveyed to the pumping mechanism via the bypass, the bypass comprises means for inhibiting propagation of a flame front therethrough.

Abstract: A vacuum pumping system comprises a primary foreline for receiving a gas stream from an outlet of a chamber, a first vacuum pump for evacuating the chamber, a second vacuum pump for evacuating the chamber, a first secondary foreline for conveying gas from the primary foreline to the first vacuum pump, a second secondary foreline for conveying gas from the primary foreline to the second vacuum pump, and valve means for selectively connecting a chosen one of the first and second secondary forelines to the primary foreline. The condition of the vacuum pumps is monitored during use. When both vacuum pumps are operating normally, the valve means is controlled to divert a first reactant-rich gas from the primary foreline into the first secondary foreline, and to divert a second reactant-rich gas from the primary foreline to the second secondary foreline, thereby inhibiting mixing of the first and second reactants within the vacuum pumps.

Abstract: In a method of inhibiting the deposition of aluminium within a vacuum pump during the pumping from a process chamber of a gas stream containing an organoaluminium precursor, chlorine is supplied to the gas stream upstream of the vacuum pump to react with the precursor to form aluminium chloride, which can pass harmlessly through the pump in its vapour phase.

Abstract: Apparatus is described for inhibiting the propagation of a flame front ignited by a pumping mechanism drawing a waste stream from a process chamber. A combustion chamber comprises an inlet for receiving the waste stream exhaust from the pumping mechanism and means for generating a flame for burning a flammable component of the waste stream. A pressure detector detects a pressure at a location through which the waste stream is drawn by the pumping mechanism, and a flame detector detects the presence of a flame in th combustion chamber. A controller regulates the delivery of at least one process fluid to the process chamber if the detected pressure is greater than a pressure above which the flame front can be sustained by the waste stream, or if there is no flame present in the combustion chamber.

Abstract: A seal assembly comprising a main O-ring seal element for engaging in a fluid tight manner opposed surfaces of two objects to be sealingly connected together and a barrier element positioned to protect all or a substantial portion of the surface of the main O-ring seal element against contact by the fluid when passing through the seal assembly from one object to the other object.