Abstract: Disclosed is a laser useful in, e.g., photolithography or medical surgery. In one embodiment, the laser comprises a discharge chamber and heat-generating electronics that are enclosed in a baffled enclosure that requires less cooling air to reliably cool the components in the enclosure than previous unbaffled enclosures. A method of reducing the amount of conditioned air is also provided. In a further embodiment, the laser has a heat-exchange system that acts quickly in response to changes in laser gas temperature by adjusting a flow-proportioning valve regulating water flow through a heat exchanger, thereby providing a continuously variable rate of heat exchange through the heat exchanger to maintain the lasing gas temperature constant. Methods of providing a laser beam and of improving the uniformity of a laser beam are disclosed, as are photolithography methods utilizing a laser and method of this invention.
Type:
Grant
Filed:
March 12, 1998
Date of Patent:
February 1, 2000
Assignee:
Cymer, Inc.
Inventors:
William N. Partio, Donald G. Larson, Igor V. Fomenkov, Anthony J. de Ruyter, Palash P. Das
Abstract: Disclosed is a laser useful in, e.g., photolithography or medical surgery. In one embodiment, the laser comprises a discharge chamber and heat-generating electronics that are enclosed in a baffled enclosure that requires less cooling air to reliably cool the components in the enclosure than previous unbaffled enclosures. A method of reducing the amount of conditioned air is also provided. In a further embodiment, the laser has a heat-exchange system that acts quickly in response to changes in laser gas temperature by adjusting a flow-proportioning valve regulating water flow through a heat exchanger, thereby providing a continuously variable rate of heat exchange through the heat exchanger to maintain the lasing gas temperature constant. Methods of providing a laser beam and of improving the uniformity of a laser beam are disclosed, as are photolithography methods utilizing a laser and method of this invention.
Type:
Grant
Filed:
January 5, 1996
Date of Patent:
May 5, 1998
Assignee:
Cymer, Inc.
Inventors:
Tom A. Watson, William N. Partlo, Donald G. Larson, Igor V. Fomenkov, Anthony J. de Ruyter, Palash P. Das
Abstract: Disclosed are copolymers of ethylene and alkyl acrylate monomers and methods of making those copolymers. Said copolymers exhibit increased melt-point temperatures and decreased hardness over similar conventional copolymers.
Type:
Grant
Filed:
June 7, 1995
Date of Patent:
May 20, 1997
Assignee:
Chevron Chemical Company
Inventors:
Jerry G. Latiolais, Nicholas R. Galante, J. Paul Gathright, James H. Wang
Abstract: Disclosed is a process for esterifying and/or transesterifying a polymer having a polyethylenic backbone and pendant acid and/or ester moieties comprising contacting a melt of the polymer with a transesterifying compound so that the polymer undergoes esterification and/or transesterification but not alcoholysis. The esterified or transesterified polymer also has pendant ester moieties which differ in kind and/or number from the unreacted polymer. In one embodiment, the process also comprises adding an amount of a transition metal salt that is effective to promote oxygen scavenging. Also in a further embodiment, the process comprises irradiating the transesterified polymer with actinic radiation to reduce the induction period before oxygen scavenging commences.Also disclosed are compositions comprising a component which comprises an ethylenic or polyethylenic backbone and a pendant or terminal moiety comprising a benzylic, allylic, or ether-containing radical.
Type:
Grant
Filed:
June 7, 1995
Date of Patent:
May 6, 1997
Assignee:
Chevron Chemical Company
Inventors:
Ta Y. Ching, Kiyoshi Katsumoto, Steven P. Current, Leslie P. Theard
Abstract: Disclosed is a process for producing normal alpha olefins having less than 1.0% saturates content, and typically no more than 0.40% saturates content. The process involves forming a mixture of normal alpha olefins and tri(higher)alkyl aluminum compounds, contacting this mixture with a cobalt-containing transalkylation catalyst, and hydrolyzing the normal alpha olefin/transalkylation catalyst mixture to minimize the amount of saturates formed. In one embodiment, the catalyst is a cobalt- and nickel-containing transalkylation catalyst. After hydrolysis, the resulting normal alpha olefins contain essentially no Group VIII metal that is capable of transalkylation.
Type:
Grant
Filed:
September 1, 1994
Date of Patent:
April 23, 1996
Assignee:
Chevron Chemical Company
Inventors:
Loren W. Hedrich, Alfred N. Kresge, Roger C. Williamson