Process for etching photomasks
OwnerMark Mueller, Serguei Komarov +1inventors
InventorsMark Mueller, Serguei Komarov, Ki-Ho Baik
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Abstract
Method and apparatus for etching a metal layer disposed on a substrate, such as a photolithographic reticle, are provided. In one aspect, a method is provided for processing a substrate including positioning a substrate having a metal photomask layer disposed on a silicon-based material in a processing chamber, introducing a processing gas at a flow rate of greater than about 350 sccm with the processing gas comprising an oxygen containing gas, a halogen containing gas, and optionally, an inert gas, into the processing chamber, generating a plasma of the processing gas in the processing chamber, generating a bias of about 50 watts or less, and etching exposed portions of the metal layer disposed on the substrate.
Claims31
A method for processing a photolithographic reticle, comprising:
- positioning the reticle on a support member in a processing chamber, wherein the reticle comprises a metal photomask layer formed on a silicon-based substrate and a patterned resist material deposited on the metal photomask layer;
- introducing a processing gas at a flow rate of at least 300 sccm, wherein the processing gas comprises an oxygen containing gas and a halogen containing gas;
- delivering power to the processing chamber to generate a plasma of the processing gas;
- supplying a bias power to the support member of greater than about 5 watts;
- and
- removing exposed portions of the metal photomask layer.
A method for processing a photolithographic reticle, comprising:
- positioning the reticle on a support member in a processing chamber, wherein the reticle comprises a chromium-based photomask layer formed on an optically transparent silicon-based material and a patterned resist material deposited on the chromium-based photomask layer;
- introducing a processing gas comprising chlorine gas and oxygen gas at a flow rate of at least 350 sccm, wherein the molar ratio between the chlorine gas and the oxygen gas is between about 1:1.5 and about 4:1;
- maintaining a chamber pressure between about 2 milliTorr and about 50 milliTorr;
- delivering power to the processing chamber of about 1000 watts or less to a coil disposed in the processing chamber to generate a plasma;
- supplying a bias power to the support member of greater than about 5 watts;
- and
- etching exposed portions of the chromium-based photomask layer;
- and
- removing the chromium-based photomask layer at a removal rate ratio of chromium-based photomask layer to resist material of about 1:1 or greater.
A method for processing a photolithographic reticle, comprising:
- positioning the reticle on a support member in a processing chamber, wherein the reticle comprises a chromium-based photomask layer formed on an optically transparent silicon-based material and a patterned resist material deposited on the chromium-based photomask layer;
- introducing a first processing gas comprising an inert gas, a halogen containing gas, and an oxygen containing gas, wherein the halogen containing gas and the oxygen containing gas have a flow rate of about 100 sccm or less;
- delivering power to the processing chamber of about 1000 watts or less to a coil disposed in the processing chamber to generate a plasma;
- introducing a second processing gas comprising a halogen containing gas and an oxygen containing gas, wherein the halogen containing gas and the oxygen containing gas have a flow rate of at least 350 sccm;
- delivering power to the processing chamber of about 1000 watts or less to a coil disposed in the processing chamber to maintain a plasma;
- supplying a bias power to the support member of greater than about 5 watts;
- and
- etching exposed portions of the chromium-based photomask layer.
The method of claim 26, wherein the second processing gas has an oxygen containing gas flow rate between about 150 sccm and 400 sccm, wherein the oxygen containing gas is selected from the group of oxygen, carbon monoxide, carbon dioxide, and combinations thereof.
Dependencies are inferred from the claim text.