Patents by Inventor Mani R. Gupta

Mani R. Gupta has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4692205
    Abstract: The use of silicon-containing polyimide as an oxygen etch barrier in a metal lift-off process and as an oxygen etch stop in the fabrication of multi-layer metal structures is described. In practice, a lift-off layer is applied on a substrate, followed by a layer of silicon-containing polyimide and a layer of photoresist. The photoresist is lithographically patterned, and the developed image is transferred into the silicon-containing polyimide layer with a reactive ion etch using a CF.sub.4 /O.sub.2 gas mixture. The pattern is transferred to the lift-off layer in a reactive ion etch process using oxygen. Subsequent blanket metal evaporation followed by removal of the lift-off stencil results in the desired metal pattern on the substrate. In an alternate embodiment, the silicon-containing polyimide can be doped with a photoactive compound reducing the need for a separate photoresist imaging layer on the top.
    Type: Grant
    Filed: January 31, 1986
    Date of Patent: September 8, 1987
    Assignee: International Business Machines Corporation
    Inventors: Krishna G. Sachdev, Ranee W. Kwong, Mani R. Gupta, Mark S. Chace, Harbans S. Sachdev