Process for defining a chalcogenide material layer, in particular in a process for manufacturing phase change memory cells
AssigneesSTMicroelectronics S.r.l., Ovonyx, Inc.
InventorAlessandro Spandre
Life of this patent
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Abstract
A process for defining a chalcogenide material layer using a chlorine based plasma and a mask, wherein the portions of the chalcogenide material layer that are not covered by the mask are etched away. In a phase change memory cell having a stack of a chalcogenide material layer and an AlCu layer, the AlCu layer is etched first using a chlorine based plasma at a higher temperature; then the lateral walls of the AlCu layer are passivated; and then the chalcogenide material layer is etched at a lower temperature.
Claims28
A process for defining a chalcogenide material layer in the manufacture of a semiconductor integrated device, comprising the steps of:
- forming a stack including said chalcogenide material layer and a metal layer positioned above the chalcogenide material layer;
- forming a mask covering the metal layer;
- etching the metal layer through the mask using a chlorine based plasma;
- and
- dry etching said chalcogenide material layer through the mask using a chlorine based plasma, wherein said step of etching said metal layer is carried out at a first temperature and said step of dry etching is carried out at a second temperature that is lower than said first temperature.
A process for defining a chalcogenide material layer in the manufacture of a semiconductor integrated device, comprising the steps of:
- forming a stack including said chalcogenide material layer and a metal layer positioned above the chalcogenide material layer;
- forming a mask covering the metal layer;
- etching the metal layer through the mask using a chlorine based plasma;
- and
- dry etching said chalcogenide material layer though the mask using a chlorine based plasma, wherein said step of dry etching is carried out at a temperature between 20° C. and 35° C.
A process for defining a wafer having a chalcogenide material layer and a metal layer, comprising:
- dry etching said metal layer using a first chlorine based plasma at a first temperature;
- passivating said metal layer using a water vapor plasma;
- and
- dry etching said chalcogenide material layer after said passivating step using a second chlorine based plasma at a second temperature, wherein said first temperature is higher than said second temperature.
A process for defining a chalcogenide material layer in the manufacture of a semiconductor integrated device, comprising the steps of:
- providing said chalcogenide material layer;
- and
- dry etching said chalcogenide material layer using a plasma that includes chlorine and oxygen gases,
- wherein the process further comprising:
- forming a stack including said chalcogenide material layer and a metal layer positioned above the chalcogenide material layer;
- forming a mask covering metal layer;
- and
- etching the metal layer through the mask, wherein the dry etching step includes dry etching said chalcogenide material layer through the mask using the plasma that includes chlorine and oxygen gases, wherein said step of etching said metal layer is carried out at a first temperature and said step of dry etching is carried out at a second temperature that is lower than said first temperature.
Dependencies are inferred from the claim text.