Extreme ultraviolet patterning process with resist hardening
A photolithography patterning stack and method for forming the same. The stack includes a plurality of patterned silicon oxide lines. A plurality of patterned silicon germanium lines each underlie and contact one patterned silicon oxide line of the plurality of patterned silicon oxide lines. The photolithography patterning stack further comprises a plurality of layers underlying the plurality of patterning silicon germanium lines. The method includes patterning at least a photoresist layer of a photolithographic patterning stack. The patterning exposing portions of a silicon germanium layer of the photolithographic patterning stack. A germanium oxide layer is formed in contact with the patterned photoresist layer and the portions of the silicon germanium layer. A plurality of silicon oxide layers is formed from the germanium oxide layer. Each of the silicon oxide layer is in contact with one of the portions of the silicon germanium layer.
1. A method of forming a photolithographic patterning structure, the method comprising:
patterning at least a photoresist layer of a photolithographic patterning stack, the patterning exposing portions of a silicon germanium layer of the photolithographic patterning stack;
forming a germanium oxide layer in contact with the patterned photoresist layer and the portions of the silicon germanium layer; and
forming, from the germanium oxide layer, a plurality of silicon oxide layers each in contact with one of the portions of the silicon germanium layer.
2. The method of claim 1 , wherein forming the plurality of silicon oxide layers comprises:
performing an anneal, wherein the anneal converts portions of the germanium oxide layer in contact with the portions of the silicon germanium layer into the plurality of silicon oxide layers.
3. The method of claim 1 , further comprising:
removing photoresist residue after the patterning of the photoresist layer, wherein the germanium oxide layer is formed after the photoresist residue has been removed.
4. The method of claim 1 , further comprising:
removing remaining portions of the germanium oxide layer after the plurality of silicon oxide layers has been formed; and
removing the patterned photoresist layer.
5. The method of claim 4 , further comprising:
transferring a pattern defined by the plurality of silicon oxide layers to the silicon germanium layer, the transferring forming a plurality of patterned silicon germanium lines; and
transferring a pattern defined by the plurality of patterned silicon germanium lines to one or more underlying layers of the photolithographic patterning stack.
6. The method of claim 1 , wherein patterning at least the photoresist layer comprises utilizing an Extreme Ultraviolet lithography process.
7. The method of claim 1 , further comprising
forming a titanium nitride layer of the photolithographic patterning stack over a substrate;
forming a tetraethyl orthosilicate based layer of the photolithographic patterning stack on and in contact with the titanium nitride layer;
forming one of an organic planarization layer or amorphous carbon layer of the photolithographic patterning stack on and in contact with the tetraethyl orthosilicate based layer; and
forming the silicon germanium layer on and in contact with the one of an organic planarization layer or amorphous carbon layer.