Self aligned double patterning flow with non-sacrificial features
AssigneeApplied Materials, Inc.
InventorsBencherki Mebarki, Li Yan Miao, Kenlin C. Huang
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Abstract
Embodiments of the present invention pertain to methods of forming features on a substrate using a self-aligned double patterning (SADP) process. A conformal layer of non-sacrificial material is formed over features of sacrificial structural material patterned near the optical resolution of a photolithography system using a high-resolution photomask. An anisotropic etch of the non-sacrificial layer leaves non-sacrificial ribs above a substrate. A gapfill layer deposited thereon may be etched or polished back to form alternating fill and non-sacrificial features. No hard mask is needed to form the non-sacrificial ribs, reducing the number of processing steps involved.
Claims18
A method of forming patterned metal features on a substrate, the method comprising:
- forming a layer of sacrificial structural material on the substrate;
- patterning the layer of sacrificial structural material using a photolithography process to form a plurality of cores with first linewidths separated by first trenches and spaced according to a first pitch;
- forming a conformal layer of a dielectric spacer material over the plurality of cores without completely filling the first trenches there between;
- anisotropically etching the conformal layer to expose the plurality of patterned sacrificial structures;
- stripping away the exposed plurality of cores leaving a plurality of non-sacrificial dielectric spacers separated by second trenches and spaced according to a second pitch that is less than the first pitch;
- filling the trenches between the plurality of non-sacrificial dielectric spacers by forming a metal layer over the non-sacrificial spacers;
- and
- planarizing the substrate to create a substantially planar surface comprising areas of dielectric spacer material and areas of metal defining the patterned metal features.
A method of forming patterned polysilicon features on a substrate, the method comprising:
- forming a layer of sacrificial structural material on the substrate;
- patterning the layer of sacrificial structural material using a photolithography process to form a plurality of cores with first linewidths separated by first trenches and spaced according to a first pitch;
- forming a conformal layer of a polysilicon material over the plurality of cores without completely filling the first trenches there between;
- anisotropically etching the conformal layer to expose the plurality of cores;
- stripping away the exposed plurality of cores leaving a plurality of non-sacrificial polysilicon features separated by second trenches and spaced according to a second pitch that is less than the first pitch;
- filling the trenches between the plurality of non-sacrificial polysilicon features by depositing a dielectric gapfill layer over the polysilicon features;
- and
- planarizing the substrate to create a substantially planar surface comprising areas of polysilicon separated by areas of dielectric defining the patterned polysilicon features.
Dependencies are inferred from the claim text.