Abstract: A system and method for the precise and uniform material removal or delayering of a large area of a sample is provided. The size of the milled area is controllable, ranging from sub-millimeter to multi-millimeter scale and the depth resolution is controllable on the nanometer scale. A controlled singularly charged ion beam is scanned across the sample surface in such a manner to normalize the ion density distribution from the sample center toward the periphery to realize uniform delayering.

Abstract: An ion source is disclosed which utilizes independently powered electrodes that are isolated with a series of insulators. The ion source comprises an anode electrode with a hollow interior, where the anode is disposed between a cathode and an anti-cathode. A magnet or electro-magnet imposes a magnetic field in an axial direction through the bore of the anode. Gas is introduced into the anode area at a controllable pressure. The ion source includes a first voltage differential between the anode and cathode for the production of plasma and a second voltage differential between the anode and the anti-cathode for extraction of ions from the plasma, forming an ion beam, which is preferably of a narrow diameter at low beam energy. In particular, the voltage differential between the anti-cathode and anode is adjusted to control the initial beam divergence of extracted ions. An optional focus electrode with an independent power supply further focuses the ion beam.

Abstract: An audible alarm detector is disclosed, consisting of a microphone, band-pass filter, counter and controller. The microphone converts the acoustic signal to an electrical signal for further processing. The band-pass filter removes frequencies different from the nominal frequency of a pulsed tone alarm. The counter detects the fundamental frequency of the filtered signal in sequential time intervals. The controller compares the counter's output for each time interval with the nominal count for the expected alarm frequency. The controller also compares the results from sequential time intervals against the nominal time-sequence of the anticipated, pulsed-tone alarm. A sufficiently close match results in a positive detection condition. An audible alarm detection method is also disclosed, consisting of low-pass filtering, followed by baseline-comparison, followed by counting, followed by discrimination based on counts, followed by comparison of discriminator output sequence versus the nominal sequence.

Abstract: An apparatus for preparing specimens for microscopy including equipment for providing two or more of each of the following specimen processing activities under continuous vacuum conditions: plasma cleaning the specimen, ion beam or reactive ion beam etching the specimen, plasma etching the specimen and coating the specimen with a conductive material. Also, an apparatus and method for detecting a position of a surface of the specimen in a processing chamber, wherein the detected position is used to automatically move the specimen to appropriate locations for subsequent processing.

Abstract: An apparatus for preparing specimens for microscopy including equipment for providing two or more of each of the following specimen processing activities under continuous vacuum conditions: plasma cleaning the specimen, ion beam or reactive ion beam etching the specimen, plasma etching the specimen and coating the specimen with a conductive material. Also, an apparatus and method for detecting a position of a surface of the specimen in a processing chamber, wherein the detected position is used to automatically move the specimen to appropriate locations for subsequent processing.

Abstract: An apparatus for preparing specimens for microscopy including equipment for providing two or more of each of the following specimen processing activities under continuous vacuum conditions: plasma cleaning the specimen, ion beam or reactive ion beam etching the specimen, plasma etching the specimen and coating the specimen with a conductive material. Also, an apparatus and method for detecting a position of a surface of the specimen in a processing chamber, wherein the detected position is used to automatically move the specimen to appropriate locations for subsequent processing.

Abstract: An ion source is disclosed which utilizes independently powered electrodes that are isolated with a series of insulators. The ion source comprises an anode electrode with a hollow interior, where the anode is disposed between a cathode and an anti-cathode. A magnet or electro-magnet imposes a magnetic field in an axial direction through the bore of the anode. Gas is introduced into the anode area at a controllable pressure. The ion source includes a first voltage differential between the anode and cathode for the production of plasma and a second voltage differential between the anode and the anti-cathode for extraction of ions from the plasma, forming an ion beam, which is preferably of a narrow diameter at low beam energy. In particular, the voltage differential between the anti-cathode and anode is adjusted to control the initial beam divergence of extracted ions. An optional focus electrode with an independent power supply further focuses the ion beam.

Abstract: A milling device is disclosed for the preparation of microscopy specimens or other surface science applications through the use of ion bombardment. The device provides the ability to utilize both gross and fine modification of the specimen surface through the use of high and low energy ion sources. Precise control of the location of the specimen within the impingement beams created by the ion sources provides the ability to tilt and rotate the specimen with respect thereto. Locational control also permits the translocation of the specimen between the various sources under programmatic control and under consistent vacuum conditions. A load lock mechanism is also provided to permit the introduction of specimens into the device without loss of vacuum and with the ability to return the specimen to ambient temperature during such load and unload operation. The specimen may be observed and imaged during all active phases of operation.

Abstract: A milling device is disclosed for the preparation of microscopy specimens or other surface science applications through the use of ion bombardment. The device provides the ability to utilize both gross and fine modification of the specimen surface through the use of high and low energy ion sources. Precise control of the location of the specimen within the impingement beams created by the ion sources provides the ability to tilt and rotate the specimen with respect thereto. Locational control also permits the translocation of the specimen between the various sources under programmatic control and under consistent vacuum conditions. A load lock mechanism is also provided to permit the introduction of specimens into the device without loss of vacuum and with the ability to return the specimen to ambient temperature during such load and unload operation. The specimen may be observed and imaged during all active phases of operation.

Abstract: An apparatus for preparing specimens for microscopy including equipment for providing two or more of each of the following specimen processing activities under continuous vacuum conditions: plasma cleaning the specimen, ion beam or reactive ion beam etching the specimen, plasma etching the specimen and coating the specimen with a conductive material. Also, an apparatus and method for detecting a position of a surface of the specimen in a processing chamber, wherein the detected position is used to automatically move the specimen to appropriate locations for subsequent processing.

Abstract: An electrical power converter for an incoming AC transformer connected to a multiphase power source and having multiple secondary windings. Each secondary winding is connected to multiple switching cells, each of which functions like a matrix converter. The secondary windings can be either single or multi-phase and more than one transformer can be provided such that the multiple secondary windings can be distributed among individual transformers. The output of at least two of the switching cells are connected in series. The switching cells can be either bi-directional or unidirectional and can also have a three-phase input. A combination of IGBTs and diodes can form the switching cells.

Abstract: Foaming of molten glass or the like as it enters a vacuum refining vessel is enhanced by altering the incoming stream so as to increase its surface area and/or retarding the passage of the stream through the vacuum headspace so as to increase its exposure to the vacuum.

Abstract: A melt of a material such as glass is inductively heated at a stage intermediate an initial liquefying stage and a refining stage. The function of the intermediate induction heating stage is essentially limited to raising the temperature of the melt a relatively minor amount to a refining temperature. Therefore, the induction heating stage may be compact with an intensified heating rate and rapid throughput, thereby permitting the induction heating zone to be a "cold" walled vessel without an appreciable effect on efficiency.

Abstract: A lid construction for a heating vessel. Discrete insulating members are supported by water cooled pipes above the vessel. The cooling pipes fit into grooves along the vertical side walls of the insulating members. Each member has a support independent from the supports for the other members so that an individual member can be removed within having to remove additional members.

Abstract: In the process for refining glass or the like by vacuum, the collapse of foam is expedited by heating the headspace within the vacuum chamber.

Abstract: Converting thermally meltable materials to a liquefied state is carried out on a lining of pulverulent material. As liquefied material is drained from the surface, additional unmelted material is fed onto the surface to maintain the lining substantially intact.

Abstract: Glass or the like is melted by liquefying batch materials in a first stage by means of radiant heating, and further advancing the melting process in a second stage where the melt is heated by induction heating. Another aspect of the invention provides a residence zone at the exit of the induction heating stage to aid elimination of gaseous inclusions.

Abstract: In a glass batch liquefying process, batch-entrained nitrogen is purged by contacting the batch with a substantially nitrogen-free gas in a pretreating stage.

Abstract: Converting thermally meltable materials to a liquefied state is carried out on a lining of pulverulent material. As liquefied material is drained from the surface, additional unmelted material is fed onto the surface to maintain the lining substantially intact.

Abstract: The initial step of melting glass, converting particulate batch materials to a partially melted, liquefied state, is carried out on a support surface of batch. As liquefied batch is drained from the surface, additional batch is fed onto the surface to maintain the surface substantially constant.The questions raised in reexamination request No. 90/000,701, filed Dec. 31, 1984 have been considered and the results thereof are reflected in this reissue patent which constitutes the reexamination certificate required by 35 U.S.C. 307 as provided in 37 CFR 1.570(e).