Patents Assigned to Epsilon Limited Partnership
  • Patent number: 4874464
    Abstract: The present invention relates to a high throughput single crystal epitaxial deposition process which achieves increased uniformity, both wafer to wafer and across the wafer surface. There is provided an epitaxial deposition process characterized by low-level cooling periods which minimize temperature changes between deposition cycles and inter-cycle cleaning so that each new wafer is presented with a substantially equivalent deposition environment.
    Type: Grant
    Filed: March 14, 1988
    Date of Patent: October 17, 1989
    Assignee: Epsilon Limited Partnership
    Inventors: Dennis L. Goodwin, Mark R. Hawkins, Wayne L. Johnson, Aage Olsen, McDonald Robinson
  • Patent number: 4789771
    Abstract: An apparatus and method for heating a substrate and associated rotatable susceptor in an epitaxial deposition reactor with an axially symmetric gas flow carrying deposition material include at least one chamber having a plurality of heat lamps. The chamber is generally symmetric with respect to an axis of the substrate. The chamber walls are coated to reflect light from the heat lamps. The outermost heat lamps can be energized to produce a higher temperature than the centrally located lamps to compensate for regions of the reactor which provide access to the substrate and, therefore, promote thermal losses. The spacing of the heat lamps may be varied to compensate for thermal non-uniformity of the heating cavity. The substrate may be rotated, on the rotatable susceptor, to average the thermal environment to which the substrate is exposed.
    Type: Grant
    Filed: March 27, 1987
    Date of Patent: December 6, 1988
    Assignee: Epsilon Limited Partnership
    Inventors: McDonald Robinson, Ronald D. Behee, Wiebe B. deBoer, Wayne L. Johnson
  • Patent number: 4654509
    Abstract: In an epitaxial deposition reactor with an axially symmetric gas flow carrying the deposition materials, apparatus and method for heating the substrate and associated susceptor uniformly is described. The apparatus includes at least one chamber having a plurality of heat lamps passing therethrough, the chamber being generally disposed symmetrically with respect to an axis of the substrate. The walls of the chamber are appropriately coated to reflect the light from the heat lamps and the outermost lamps can be energized to produce a higher temperature than the centrally located lamps to compensate for regions of the reactor that provide access to the substrate and therefore promote thermal losses. The spacing of the lamps can be varied also to compensate for thermal non-uniformity of the heating cavity. In a first embodiment, a lower chamber can be a chamber similar to the first chamber with the exception that the lamps are rotated 90.degree..
    Type: Grant
    Filed: October 7, 1985
    Date of Patent: March 31, 1987
    Assignee: Epsilon Limited Partnership
    Inventors: McDonald Robinson, Ronald D. Behee, Wiebe B. deBoer, Wayne L. Johnson