Patents Represented by Law Firm Workman Nudegger & Seeley
  • Patent number: 5942131
    Abstract: A surface having an exposed silicon/silica interface is cleaned by ah HF dip, followed immediately by a rinse in citric acid, followed by a rinse in deionized water. Low pH of the citric acid significantly prevents the formation of a charge differential between the silica and silicon portions of the surface, which charge differential would otherwise cause any silica particles present to remain on the silicon portion of the surface. Surfactant properties of the citric acid help remove any silica particles from the surface. The deionized water rinse then removes the citric acid from the surfaces, leaving a very clean, low particulate surface on both the silica and silicon portions thereof, with little or no etching of the silicon portion.
    Type: Grant
    Filed: June 17, 1997
    Date of Patent: August 24, 1999
    Assignee: Micron Technology, Inc.
    Inventors: Karl M. Robinson, Michael A. Walker