Abstract: An apparatus for improving dose uniformity in the PLAsma Doping (PLAD) ion implantation of a target material is described. By providing means for simultaneously biasing both the electrode, upon which the target is disposed, and a separately biasable concentric structure introduced about the electrode and sufficiently close to the target, together with means for adjustable bias variation between the electrode and the structure one can sufficiently adjust the shape of the implantation plasma, e.g. induced electric field and plasma sheath thickness, in order to effectively provide a uniform dose distribution during PLAD ion implantation processes.

Abstract: A molecular drag compressor includes a rotor disk and a stator that defines a tangential flow channel having an inlet and an outlet. A stationary baffle is disposed in the tangential flow channel adjacent to the outlet. The baffle is spaced from the rotor disk by a gap. A surface of the baffle facing the rotor disk has surface irregularities including peaks for defining the gap and valleys between the peaks for accumulation of particles. The surface irregularities may form a series of grooves. The molecular drag compressor is preferably utilized in a high vacuum pump which includes an axial turbomolecular compressor and a molecular drag compressor. Additional features which limit the effect of particulate accumulation in molecular drag compressors are disclosed.

Abstract: A peristaltic pump comprises a rotatable drum 2 having rollers 5 or cams 5' for squashing a flexible tube 9 against a profiled surface 10 of a presser plate 7. Tube 9 is mounted between supports 14 and 15 on presser plate 7 and is automatically movable between an inoperative and operative (pumping) position by pivotal movement of plate 7 about axis 8 produced by an electro mechanical actuator. A flexible membrane 33 is sandwiched between rollers 5 or cams 5' for eliminating shear forces on the tube 9. The construction of the pump and shape of profile 10 are such as to mimimise pulsations in the output flow. Systems for supplying a sample for analysis to spectroscopic apparatus using the peristaltic pump are also described.

Abstract: A sample delivery system for a flow-through NMR analysis is provided, which utilizes pressurized gas as a means for conveying a sample into and out of an NMR spectrometer. Two sources of gas pressure, a forward pressure and back pressure, oppose the sample within the tubing of the sample delivery system and the tubing of the flow-through system which are operatively coupled together. Conveyance of the sample in any direction within the tubing is achieved by adjusting the pressure differential. Precise positioning of the sample in the magnetic field center and complete removal of the sample from the NMR spectrometer when analysis is complete are achieved by using a signal processor which receives signals from the NMR detector or other detectors positioned along the length of the tubing. These signals provide an indication of the position of the sample in the tubing. The signal processor uses this information to adjust the forward and back pressure, thereby achieving the desired positioning of the sample.

Abstract: A method and apparatus are provided which increase the collimation of sputter deposited films by increasing the mean free path (MFP) of sputtered atoms so as to reduce redirecting collisions with the buffer gas. This is accomplished by reducing buffer gas pressure while employing mechanisms to maintain or increase plasma electron density so as to sustain the plasma in the absence of normally required gas pressure. A first mechanism used to permit reduced gas pressure is to provide gas flow directly to the immediate region of the plasma discharge rather than to another remote area of the sputter deposition chamber. A second mechanism used to permit reduced gas pressure is to provide an electron emitting source near the plasma discharge to increase the plasma electron density without requiring further ionization of buffer gas atoms. These two mechanisms can be used either alone or together, as desired, in view of the circumstances presented.

Abstract: A broadband optical detector is disposed to measure the total intensity I(.lambda., .alpha.) attributed to a portion of the optical spectrum passed by a sharp bandgap optical transmission element as the bandgap is caused to translate over a desired wavelength interval by a band gap control parameter, T. The differential spectrum of the incident optical radiation is recovered by the differentiation of I(.lambda., .alpha.) in respect to the parameter T.

Abstract: An optical pulse propogating in an optical guide of an electro-optic medium interacts with a coplanar RF traveling wave to shift the optical wavelength. The RF phase is resynchronized to the optical pulse phase with spatial periodicity to provide a desired phase relationship between RF and optical radiation. A unidirectional incremental wavelength shifter comprises a frequency multiplexer for soliton communication and a symmetrical sideband modulator of this type varies the spectral width of probe illumination in an atomic absorption spectrometer probe beam.

Abstract: Disclosed is a low cost computer tomographic (CT) scanner system specifically designed for radiation therapy treatment planning. A 512-channel photo-diode array with digitizing electronics converts image intensifier optical projection data directly into digital signals and has a dynamic range on the order of 100,000:1. The new simulator includes a rotating gantry, an X-ray generator with radiographic and fluoroscopic modes and a therapy style patient support assembly. Results on head and body size phantoms indicate that the simulator X-ray generator and image intensifier tube (IIT) with multi-channel photo-detector can produce photon statistic limited CT images. Software and hardware compensation methods are described which minimize geometrical distortions. Low noise, high input impedance electronics are employed which are phase-locked to the line frequency.

Abstract: An apparatus is described for carrying out solid phase microextraction and analysis of analytes in a fluid carrier in which a fiber within a housing is vibrated by a vibrating means during microextraction. The housing contains access means so that the carrier and analytes can be brought into contact with the vibrating fiber during the extraction stage. In a preferred embodiment of the present invention, the vibrating means comprises a membrane, a solenoid for vibrating the membrane, a frame, a retainer mounted on the frame for holding the solenoid, a holder for the membrane, and a retainer arm having one end connected to the retainer and the other end attached to the holder. A method for microextraction and analysis is also described in which a vibrating fiber is placed into contact with analytes to be analyzed in a suitable carrier deposited in a container for a sufficient period of time for microextraction to occur.

Abstract: An apparatus and method for precisely calibrating the transfer arm of a multiple station wafer processing system without breaking vacuum and with a minimum of system downtime is provided. A system of determining and properly aligning the crystallographic orientation of the wafers before processing as well as monitoring the orientation of individual wafers during wafer transfer between processing stations is also provided.

Abstract: A thin film which is substantially free of measurable surface defects due to second-phase inclusions is disclosed. The film is composed of multilayered strata of a first metal oxide interspersed with single molecular layers of a second metal oxide, where the second metal oxide is effective to absorb second-phase defects which form in the first oxide layers.

Abstract: The present invention provides an X-ray generating apparatus with a shield structure having an electron beam collimating aperture and heat transfer device. The shield structure is made of thermally conductive material and placed in the discharge space between an electron source and rotating anode target. The shield structure is formed by a concave top surface facing the electron source, a flat top surface facing the anode target, and inner and outer walls wherein a linear dimension of the inner wall is substantially smaller than the linear dimension of the outer wall. The inner wall surrounds the beam collecting aperture. The heat transfer device is placed in a beveled portion of the shield structure. The heat transfer device includes an extended coiled wire formed from thermally conductive material and conductively attached to the knurled interior of the shield structure to transfer heat to the cooling liquid passing through inflow and outflow chambers of the shield structure.

Abstract: A turbomolecular pump comprises a pump body housing a gas inlet and a gas exhaust port and a plurality of pumping assemblies with interleaved rotors and stators located within the pump body. The rotors are secured to a rotating shaft that is supported by at least one rotatable support and driven by a motor. At least one stator of the pumping assemblies is provided with at least one spiral channel adapted to push and eject the gases from an area proximal to the shaft toward an area distal from the shaft and vice versa.

Abstract: A stationary target anode of an X-ray device is provided, having stepped high Z button configuration. By minimizing the diameter of the central, X-ray producing section of the button, and incorporating a thin lip extending therefrom to a diameter approximately twice that of the central portion, internal and interface stresses are minimized. A flexible structure is also provided to support the button/substrate assembly and provide minimal resistance as the substrate radially expands during heating, thereby minimizing induced stress on the target and preventing fatigue and failure of the support target.

Abstract: The thin film heat treatment apparatus for heating the wafers or foil sheets provides a conductively heated table disposed within a vacuum chamber, a heat radiation preventing device that is installed adjacent to the conductively heated table and forms a space with the top of the heater table by surrounding the foil sheet or wafer placed on the top of the heater table.

Abstract: A mass spectrometer system for performing a separation of ions from neutrals and mass analyzing ions comprising an ion generating source with an ion introduction system, a radio-frequency ion guide and a mass analyzer disposed within a vacuum chamber. The radio-frequency ion guide is positioned with respect to the ion introduction system so that a main axis of the radio-frequency ion guide is angled toward a central axis of the ion introduction system. The trajectory of the ions is diverted toward the main axis of the radio-frequency ion guide while neutrals continue their flow along the central axis. The ions from the ion introduction system are transported via the radio-frequency ion guide to the mass analyzer.

Abstract: A chromatography system and method employing an empirical method for determining the ratio ##EQU1## for a chromatography column with improved accuracy by establishing experimental conditions for at least one of the parameters of temperature, pressure and flow and measuring the other parameters and calculating the ratio ##EQU2## using the Poiseville equation for a chromatography column.

Abstract: Longitudinally collapsible apparatus for compacting packing material within a tubular liquid chromatography column. The apparatus includes a first support member, a second support member and a movable support member. The movable support member is releasably connectable to the second support member for support thereby. When released from the second support member, the movable member is adapted to ride on guide members extending between the first and second support members. A compression mechanism is supported on the movable support member to mote therewith to a longitudinally collapsed position for the apparatus. The compression mechanism comprises a reversible drive for an axially movable rod carrying a movable piston. With the movable support member secured to the second support member, the piston of the compression mechanism is movable in an end of the tubular column when the column is supported on the first support member.

Abstract: The present invention is directed to a dual frequency capacitively-coupled plasma apparatus for materials processing. According to a first aspect of the present invention, a dual frequency triode reactor includes a VHF (30-300 MHz) RF power supply capacitively coupled to an upper reactor electrode and an HF (0.1-30 MHz) RF power supply capacitively coupled to a lower reactor electrode to which the wafer is attached. The VHF power supply is used to generate and control formation of a low sheath potential, high density plasma for minimum device damage and rapid etching/deposition while the HF power supply is used to provide a DC bias to the wafer substrate. According to a second aspect of the present invention, a tailored, powered upper electrode, at least a portion of which is generally conical in shape, is employed to provide a uniform etch across the diameter of the wafer.

Abstract: A method for treating M-degree oversampled impulse response data in real time includes generating N initial pseudo-data points derived from an N tap digital filter, processing each datum therewith, down sampling by a factor of r and displacing the processed datum toward the time origin by an appropriate amount. After fourier transform of the data set, the spectral background information bears improved fidelity to the actual spectral noise.