Vacuum-integrated hardmask processes and apparatus
Vacuum-integrated photoresist-less methods and apparatuses for forming metal hardmasks can provide sub-30 nm patterning resolution. A metal-containing (e.g., metal salt or organometallic compound) film that is sensitive to a patterning agent is deposited on a semiconductor substrate. The metal-containing film is then patterned directly (i.e., without the use of a photoresist) by exposure to the patterning agent in a vacuum ambient to form the metal mask. For example, the metal-containing film is photosensitive and the patterning is conducted using sub-30 nm wavelength optical lithography, such as EUV lithography.
1. An apparatus for conducting photoresist-less metal mask formation, the apparatus comprising:
a metal-containing film deposition module comprising a reactor chamber for depositing a EUV-sensitive metal-containing film;
a metal-containing film patterning module comprising an Extreme Ultraviolet (EUV) photolithography tool with a source of sub-30 nm wavelength radiation;
a vacuum transfer module connecting the deposition module and the patterning module; and
a controller including one or more memory devices, one or more processors and system control software coded with instructions for conducting photoresist-less metal mask formation, the instructions comprising instructions for:
in the metal-containing film deposition module, depositing on a semiconductor substrate a EUV-sensitive metal-containing film of solid SnBr 4 having a thickness of between 5 and 200 nm;
transferring the substrate under vacuum to the metal-containing film patterning module; and
in the metal-containing film patterning module, patterning the metal-containing film with sub-30 nm resolution directly by EUV exposure having a wavelength in the range of 10 to 20 nm in a vacuum ambient to form a metal hardmask.
2. The apparatus of claim 1 , further comprising an ingoing load lock for transferring a substrate from the patterning module to the vacuum transfer module, and an outgoing load lock for transferring a substrate to the patterning module from the vacuum transfer module; and wherein the outgoing load lock functions as an outgassing module.
3. The apparatus of claim 1 , wherein according to the instructions the EUV exposure has a wavelength of 13.5 nm.
4. The apparatus of claim 1 , further comprising instructions for developing the pattern outside the patterning module to form the metal hardmask.
5. The apparatus of claim 4 , wherein the pattern development instructions comprise heating the semiconductor substrate to volatilize unexposed regions of the metal-containing film.
6. The apparatus of claim 1 , wherein the metal-containing film patterning module is a EUV lithography processing chamber for the patterning.
7. The apparatus of claim 1 , wherein according to the instructions the solid film is of SnBr 4 having a thickness of between 5 and 200 nm, and is deposited at a temperature between about 0 and 30° C. at a reactor pressure of less than 20 Torr.
8. The apparatus of claim 7 , wherein according to the instructions the solid film is of SnBr4 having a thickness of 10 nm, deposited at a reactor pressure maintained between 14 and 15 Torr at 20° C.
9. The apparatus of claim 7 , wherein according to the instructions the patterning by Extreme Ultraviolet lithography (“EUVL”) involves the following decomposition chemistry: SnBr 4 →Sn+2Br 2 .
10. An apparatus, comprising:
a semiconductor process cluster tool architecture comprising a plurality of processing modules, each of the modules configured for dry processing of a semiconductor substrate, and each of the modules connected by vacuum transfer module interfaces, such that organotin-based EUV resist film dry deposition, patterning and development modules are vacuum-integrated, the cluster tool architecture further comprising,
an organotin film dry deposition module comprising a reactor chamber for dry depositing an EUV-sensitive organotin film on a substrate,
a patterning module comprising an Extreme Ultraviolet (EUV) photolithography tool with a source of sub-30 nm wavelength radiation for exposing a portion of the EUV-sensitive organotin film on a substrate to EUV radiation to form a pattern,
a dry development module for removing an unexposed portion of the pattern in the organotin film on the substrate,
and vacuum transfer module interfaces connecting the deposition, patterning and development modules of the cluster tool architecture;
the apparatus further comprising:
a controller including one or more memory devices, one or more processors and system control software coded with instructions for conducting photoresist-less metal mask formation, the instructions comprising instructions for:
in the organotin film dry deposition module, dry depositing, on the semiconductor substrate the EUV-sensitive organotin film;
following the dry deposition, transferring the substrate under vacuum to the patterning module comprising the Extreme Ultraviolet (EUV) photolithography tool and exposing the portion of the organotin film on the substrate to EUV radiation to form the pattern;
and following the EUV patterning, transferring the substrate under vacuum to the dry development module for removing the unexposed portions of the pattern in the organotin film on the substrate.