Abstract: An apparatus and method for implanting a desired chemical species in a semiconductor substrate. The apparatus comprises a target chamber, a holder to hold a substrate in the target chamber for implantation, a pump to pump the target chamber down to a desired pressure, a pressure lock to enable a substrate to be passed into the target chamber for loading on the holder while the target chamber is at sub-atmospheric pressure, an ion beam generator for generating and directing a beam of ions containing said desired species at a surface of a substrate on said holder, and a reactive gas supply to feed a reactive gas into the target chamber while the chamber is maintained by the pump at the desired pressure, to provide a desired partial pressure of the reactive gas in the target chamber to reactive with and volatilise unwanted contaminants on surfaces in the target chamber.

Abstract: A system for implanting ions of a prearranged chemical species into a plurality of semiconductor wafers. A beam analyzing arrangement receives an ion beam and selective separates various ion species in the beam on the basis of mass to produce an analyzed beam exiting the analyzing arrangement. A wafer scanning arrangement scans a plurality of wafers through the accelerated ion beam. The analyzing arrangement has an ion dispersion plane associated therewith and the source arrangement has an associated ion emitting envelope including an area pf substantial extension in a plane parallel to the ion dispersion plane and produces an ion beam characterized by a beam envelope which retains an area of substantial extension in a plane paralled to ion dispersion plane throughout the region between the source and the analyzing arrangement and by ions entering the analyzing arrangement travelling substantially either toward or from a common apparent line object perpendicular to the ion dispersion plane.

Abstract: Method and apparatus for the control of the rate of emission of electrons added to an ion implantation beam to neutralize charging effects on semiconductor wafers being processed. A net charging current, or equivalent voltage, is sensed continuously, but is sampled only when a selected wafer, or multiple selected wafers, are positioned to receive the entire cross section of the ion beam. The sampled charging current is used to control the addition of charge-neutralizing electrons to the ion beam, thereby eliminating problems that ensue from the use of an averaged charging current that is sensed without regard to the relative beam position or the number of wafers being processed.

Abstract: A system and methods for handling semiconductor wafers and dummy wafers in semiconductor process equipment such as an ion implanter. Tray assemblies are provided, each of which is adapted for releasably holding and automatically aligning a standard semiconductor wafer cassette next to a dedicated dummy-wafer cassette. The dummy wafers are used to complete a full load of wafers when there are insufficient wafers in the standard cassette. The trays are mounted on the paddles of a load lock carousel, which indexes the trays to an unloading/loading station. There, an indexer assembly picks up and indexes the tray so that the standard and dummy wafers can be selectively lifted by a vertical transport mechanism to a pivotal wafer chuck for transfer into the process equipment.

Abstract: A dual mechanical movement scanning system for ion implantation includes a radial scan arm which is mounted at a fixed pivot point external to the system vacuum chamber and penetrates the chamber and supports the wafer paddle or wheel within the chamber. The fast-scan component is provided by rotation of the paddle on the support arm; the slow-scan component is provided by pivotal movement of the scan arm itself. The drive system which reciprocally pivots the radial scan arm is configured geometrically so that controlled movement of one arm of the drive system is translated as l/r velocity of the rotational axis relative to the beam path. The wafer paddle can be constructed to provide a variable implant angle and to use a component of centrifugal force to hold the wafers in place without clamps or other mechanical means.

Abstract: A bulk acoustic wave delay line adapted to increase triple-transit signal suppression by selective aperture limiting, the device including a bulk acoustic wave-supporting body having a planar end face at each end of the bulk acoustic wave propagation path, the device also including an annular absorbing structure disposed on at least one of the end faces immediately adjacent to and surrounding a transducer for absorbing the portion of the propagating bulk acoustic wave energy impinging on an end face not covered by the transducer.

Abstract: A bulk wave acoustic wave device with electrodes fabricated on a crystal in the form of arrays each having a plurality of closely spaced electrodes, one array being angularly disposed with respect to the other to provide at least one pair of matching electrodes notwithstanding uncontrolled beam wander within the crystal.

Abstract: A bulk acoustic wave delay line including a body of acoustic wave supporting material and having at least one planar surface capable of reversably converting longitudinal wave mode acoustic energy to shear wave mode acoustic energy, the delay line also including at least one transducer for converting electromagnetic wave energy to acoustic wave energy and vice versa for propagating said acoustic wave energy along a path, a major portion of which supports shear wave mode energy and which path is at least partially defined by the mode converting planar surface, the planar surface being treated to increase the attenuation of propagating acoustic wave energy thereat by a predetermined amount, the attenuation provided at said planar surface being relatively frequency independent as compared to the attenuation per unit time of the propagating acoustic wave energy in the delay line body whereby triple transit signal suppression is significantly increased while still maintaining a relatively wide band frequency respo