Method of manufacturing a semiconductor device
AssigneeFujitsu Limited
InventorsKenji Sugishima, Tadakazu Takada
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Abstract
A method of manufacturing a semiconductor device having a multi-layer structure comprises the steps of patterning in accordance with a predetermined pattern a thin film of photoresist formed on a film to be etched which has been formed on a semiconductor substrate, etching the film to be etched partly by an isotropic etching using said patterned film as a mask, completing the etching by an anisotropic etching in the direction of its depth, resulting in tapered or inclined sides on the etched film. The isotropic and anisotropic etchings may be carried out in the same apparatus by changing the reactive gases used in these etchings and/or the conditions of each etching, such as the amount of gas, the gas pressure and the applied radio frequency power.
Claims36
A method of manufacturing a semiconductor device with a multi-layer structure on a semiconductor substrate to have a more uniform thickness of at least one of the layers, said method comprising the steps of
- forming a masking film with a predetermined pattern on a selected one of said layers that is to be etched in forming said multi-layer structure,
- isotropically etching each portion of said layer exposed by said pattern to a substantial depth of said selected layer with a respective etchant, leaving at least a lower part of each said exposed portion of said selected layer, said isotropic etching resulting in the removal of at least some of said selected layer underneath said masking film at the edges of said predetermined pattern, and
- completing removal of said selected layer in an area of each said lower part by anisotropic etching so that the lower surface of said selected layer has said predetermined pattern,
- wherein the combination of said etchings result in the selected layer having said predetermined pattern with tapered edges.
Dependencies are inferred from the claim text.