Patents Represented by Attorney Robert A. Chittun
  • Patent number: 5124717
    Abstract: An ink jet printhead having an integral membrane filter fabricated over the surface of the printhead containing the ink inlet is disclosed. The individual printheads are obtained by a sectioning operation which cuts aligned and bonded channel and heater wafers. The mated wafers contain a plurality of printheads and must be separated. The integral membrane filter is formed on the channel wafer after it is anisotropically etched incorporating the etch resistant mask layer and prior to mating with the heater wafer. A patternable layer is deposited over the etch resistant masking layer and exposed, patterned and developed to establish the mesh filter. In one embodiment, the side of the channel wafer not patterned and etched is heavily doped to form an etch stop which increases the robustness of the membrane filter by ensuring that the masking layer remains intact during subsequent fabricating steps.
    Type: Grant
    Filed: December 6, 1990
    Date of Patent: June 23, 1992
    Assignee: Xerox Corporation
    Inventors: Michael R. Campanelli, William G. Hawkins, Donald J. Drake, James F. O'Neill