Integral patterning of large features along with array using spacer mask patterning process flow
AssigneeApplied Materials, Inc.
InventorsChristopher Dennis Bencher, Jing Tang
Life of this patent
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Abstract
Embodiments of the present invention pertain to methods of forming patterned features on a substrate having an increased density (i.e. reduced pitch) as compared to what is possible using standard photolithography processing techniques using a single high-resolution photomask while also allowing both the width of the patterned features and spacing (trench width) between the patterned features to vary within an integrated circuit.
Claims22
A method of forming patterned features on a substrate, the method comprising:
- forming a sacrificial structural layer of a core material on the substrate;
- forming a protective layer of a protective material on the sacrificial structural layer;
- patterning the sacrificial structural layer and the protective layer to form patterned structures and regions of exposed substrate, the patterned structures including at least two narrow patterned structures having a first linewidth and a first spacing and at least one wide patterned structure having a second linewidth which is greater than the first linewidth, the narrow and wide patterned structures each comprising a layer of the protective material over a layer of the core material;
- etching the protective material such that the protective material is substantially removed from the at least two narrow patterned structures (leaving behind at least two narrow cores) and a portion of the protective material remains on the at least one wide patterned structure (leaving behind a protective portion on a wide core);
- forming a conformal layer of a spacer material over the remaining structures and exposed substrate;
- anisotropically etching the conformal layer to expose the at least two narrow cores and regions of exposed substrate;
- and
- removing the at least two narrow cores.
A method of patterning a substrate having a layer of protective material formed over a sacrificial layer of core material using a single high-resolution photomask, the method comprising:
- depositing a layer of photoresist over the layer of protective material;
- patterning the layer of photoresist by exposing the layer of photoresist to radiation through the single high-resolution photomask and developing the layer of photoresist to form a first pattern defined by the high-resolution photomask, the first pattern including a plurality of narrow structures having a first width and a first pitch and at least one wide structure having a second width greater than the first width;
- transferring the first pattern into the layer of protective material and the layer of core material to form patterned stacks of protective material over sacrificial material including a plurality of narrow stacks corresponding to the plurality of narrow structures and at least one wide stack corresponding to the at least one wide structure;
- and
- etching the layer of protective material using a self-limiting isotropic etch process to remove substantially all protective material from the plurality of narrow stacks leaving behind a plurality of narrow cores and leaving protective material on the at least one wide stack.
Dependencies are inferred from the claim text.