Patents by Inventor Yosias Melaku

Yosias Melaku 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: 6653058
    Abstract: A method of removing photoresist material from a semiconductor substrate includes providing a semiconductor substrate having a patterned photoresist mask. A layer comprised of polymer material is formed over the patterned photoresist mask. The layer comprised of polymer material and a portion of the patterned photoresist mask are then removed. The layer comprised of polymer material is preferably formed by introducing a process gas into a plasma environment and is preferably formed with less thickness in a low aspect ratio area relative to a high aspect ratio area.
    Type: Grant
    Filed: September 6, 2001
    Date of Patent: November 25, 2003
    Assignee: Lam Research Corporation
    Inventors: Vahid Vahedi, Yosias Melaku
  • Patent number: 6432832
    Abstract: A method of performing a shallow trench isolation etch in a silicon layer of a layer stack is disclosed. The layer stack includes a silicon layer being disposed below a pad oxide layer, the pad oxide being disposed below a nitride layer, and the nitride layer being disposed below a photoresist mask. The etching takes place in a plasma processing chamber. The method includes flowing a first etchant source gas into the plasma processing chamber, forming a first plasma from the first etchant source gas, and etching through the nitride layer with the first plasma. The method further includes flowing a second etchant source gas into the plasma processing chamber, forming a second plasma from the second etchant source gas, and substantially removing the photoresist mask with the second plasma, wherein a substantial portion of the photoresist mask is removed from above the nitride layer before the silicon layer.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: August 13, 2002
    Assignee: Lam Research Corporation
    Inventors: Alan J. Miller, Yosias Melaku
  • Publication number: 20020018965
    Abstract: A method of removing photoresist material from a semiconductor substrate includes providing a semiconductor substrate having a patterned photoresist mask. A layer comprised of polymer material is formed over the patterned photoresist mask. The layer comprised of polymer material and a portion of the patterned photoresist mask are then removed. The layer comprised of polymer material is preferably formed by introducing a process gas into a plasma environment and is preferably formed with less thickness in a low aspect ratio area relative to a high aspect ratio area.
    Type: Application
    Filed: September 6, 2001
    Publication date: February 14, 2002
    Inventors: Vahid Vahedi, Yosias Melaku
  • Patent number: 6316169
    Abstract: A method of removing photoresist material from a semiconductor substrate includes providing a semiconductor substrate having a patterned photoresist mask. A layer comprised of polymer material is formed over the patterned photoresist mask. The layer comprised of polymer material and a portion of the patterned photoresist mask are then removed. The layer comprised of polymer material is preferably formed by introducing a process gas into a plasma environment and is preferably formed with less thickness in a high aspect ratio area relative to a low aspect ratio area.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: November 13, 2001
    Assignee: Lam Research Corporation
    Inventors: Vahid Vahedi, Yosias Melaku