Rework and stripping of complex patterning layers using chemical mechanical polishing
A method utilizing a chemical mechanical polishing process to remove a patterned material stack comprising at least one pattern transfer layer and a template layer during a rework process or during a post pattern transfer cleaning process is provided. The pattern in the patterned material stack is formed by pattern transfer of a directed self-assembly pattern generated from microphase separation of a self-assembly material.
1. A method for making a semiconductor structure comprising:
forming a patterned template layer over a pattern transfer layer located on a hardmask layer, wherein the patterned template layer comprises at least one opening exposing a portion of the pattern transfer layer, and wherein the forming the patterned template layer over the pattern transfer layer comprises:
providing a template layer over the pattern transfer layer,
forming a photoresist layer on a top surface of the template layer,
patterning the photoresist layer to define the at least one opening in the photoresist layer, and
transferring the at least one opening into the template layer,
wherein the template layer has a multilayer structure comprising an organic planarization layer (OPL) present on the pattern transfer layer and an antireflective coating (ARC) layer present on the OPL;
forming a patterned structure in the at least one opening, the patterned structure comprising a first self-assembled region and a second self-assembled region;
removing the second self-assembled region to provide a first pattern, wherein the first pattern is defined by the first self-assembled region;
transferring the first pattern into the pattern transfer layer to provide a second pattern formed in a patterned pattern transfer layer; and
performing chemical mechanical polishing (CMP) to remove the first self-assembled region, the patterned template layer and the patterned pattern transfer layer while leaving the hardmask layer unremoved.
2. The method of claim 1 , further comprising performing an anisotropic etch to remove a major portion of the first self-assembled region prior to the performing the CMP, wherein the CMP removes a residue of the first self-assembled region that remains on exposed surfaces of the patterned template layer and the patterned pattern transfer layer after performing the anisotropic etch.
3. The method of Claim 1 , wherein the ARC layer comprises a SiARC.
4. The method of claim 1 , wherein the first self-assembled region comprises a first component of a block copolymer and the second self-assembled region comprises a second component of the block copolymer.
5. The method of claim 4 , wherein the block coploymer comprises poly(styrene-b-methyl methacrylate), poly(styrene-b-vinyl pyridine), poly(styrene-b-butadiene), poly(styrene-b-isoprene), poly(styrene-b-alkenyl aromatics), poly(isoprene-b-ethylene oxide), poly(styrene-b-(ethylene-propylene)), poly(ethylene oxide-b-caprolactone), poly(butadiene-b-ethylene oxide), poly(styrene-b-t-butyl (meth)acrylate), poly(methyl methacrylate-b-t-butyl methacrylate), poly(ethylene oxide-b-propylene oxide), poly(styrene-b-tetrahydrofuran), poly(styrene-b-dimethylsiloxane), poly(styrene-b-ferrocenyldimethylsilane), poly(styrene-b-isoprene-b-ethylene oxide), poly(styrene-b-isoprene-b-methyl methacrylate), or poly(styrene-b-ferrocendimethylsilane-b-isoprene).
6. The method of claim 1 , wherein the hardmask layer comprises titanium nitride or silicon oxide.
7. The method of claim 1 , wherein the performing the CMP is conducted under a pressure from 0.5 psi to 2 psi.
8. The method of claim 1 , wherein the forming the patterned structure comprises:
depositing a self-assembly material in the at least one opening; and
annealing the self-assembly material to cause microphase separation of the self-assembly material, wherein the self-assembly material is a block copolymer.
9. The method of claim 1 , wherein the pattern transfer layer comprises another OPL and another ARC present on the another OPL.
10. The method of claim 9 , wherein the another OPL comprises near-frictionless carbon (NFC) material, diamond-like carbon, polyarylene ether, or polyimide.
11. The method of claim 9 , wherein the another ARC layer comprises a silicon-containing ARC (SiARC).
12. The method of claim 1 , wherein the performing the CMP comprises using a CMP slurry.
13. The method of claim 12 , wherein the CMP slurry comprises silicon abrasive particles.
14. The method of claim 12 , wherein the CMP slurry has a pH value from 6 to 10.5.
15. The method of claim 1 , wherein the hardmask layer is present over a substrate.
16. The method of claim 15 , wherein the substrate comprises silicon, silicon oxide, aluminum, aluminum oxide, gallium arsenide, ceramic, quartz, or copper.
17. The method of claim 15 , further comprising transferring the second pattern into the hardmask layer prior to the performing the CMP.