Abstract: A method for fabricating thin smooth films of a planar metal oxide superconductor is disclosed. Fabrication of the superconductor film comprises depositing, on a substrate, a film of the planar metal oxide superconductor having a thickness greater than desired, and thinning at least a portion of the superconductor film to the desired thickness. In a particular embodiment of the method, thinning comprises exposing the superconductor film to a low energy ion beam directed at grazing incidence to the superconductor surface. Thin superconductor films fabricated in accordance with this method typically have substantially smooth surfaces and can have relatively low RF loss. These films can be advantageously used, inter alia, in RF striplines, microwave cavities and waveguides, bolometers, SQUIDs, and other Josephson junction devices.
Abstract: Described is a method for forming epitaxial films comprising successive layers of at least ternary and at least quaternary III-V material grown by metalorganic vapor-phase epitaxy. Between the steps of growing successive layers, the growth chamber is first flushed, advantageously in successive steps using a pair of gaseous Group V hybrides, a few monolayers of binary III-V material are then deposited, and then the growth chamber is again flushed. As a result, interfaces are sharper and interfacial defects are reduced. Also described are quantum well lasers made according to the inventive method.
Type:
Grant
Filed:
June 15, 1989
Date of Patent:
August 28, 1990
Assignee:
AT&T Bell Laboratories
Inventors:
Ralph A. Logan, Tawee Tanbun-ek, Henryk Temkin
Abstract: Disclosed is a method of semiconductor device fabrication involving the detection of water in a dielectric layer that is part of the body of such device. At relatively high values of a voltage applied across the dielectric layer, water that is present in the dielectric decomposes and releases protons. Varying the applied voltage gives rise to a displacement current. The released protons contribute an ionic component to the displacement current. The ionic component is detected.
Type:
Grant
Filed:
August 18, 1989
Date of Patent:
July 3, 1990
Assignee:
American Telephone and Telegraph Company
Inventors:
John M. Andrews, Jr., Nadia Lifshitz, Gerald Smolinsky
Abstract: A new method for fabricating optical assemblies (OAs), which achieves increased throughput and reduced unit cost by mass producing optical subassemblies (OSAs), is disclosed. In accordance with this method, at least two OSAs are simultaneously produced by initially forming at least two corresponding sets of electrically conductive regions on the surface of a substrate. At least two optoelectronic devices are mounted on the surface of the substrate, with each device in electrical contact with one of the two conductor sets. Afterward, the substrate is separated into at least two parts, with each part including one of the optoelectronic devices and one of the conductor sets, constituting an OSA. Each OSA is then incorporated into an OA.
Type:
Grant
Filed:
May 17, 1989
Date of Patent:
May 22, 1990
Assignee:
AT&T Bell Laboratories
Inventors:
Richard J. Pimpinella, John M. Segelken
Abstract: A method for fabricating a polarization rotator which includes a thin film waveguide exhibiting essentially zero linear birefringence in the absence of an externally applied stress, as well as an optical system incorporating said rotator, is disclosed.
Type:
Grant
Filed:
October 19, 1987
Date of Patent:
December 12, 1989
Assignee:
American Telephone and Telegraph Company
Abstract: Apparatus comprising a bakeable high vacuum system using cryopumps is disclosed. Auxiliary cooling means in thermal contact with the primary pumping stage of the cryopump remove heat from the cryopump, whereby the walls of the cryopump may be heated during operation of the cryopump, such that the cryopump can be baked. This can result in substantially improved attainable pressure in the system.
Type:
Grant
Filed:
November 23, 1988
Date of Patent:
October 17, 1989
Assignee:
American Telephone Telegraph Company, AT&T Bell Laboratories