METHOD AND SYSTEM FOR XENON FLUORIDE ETCHING WITH ENHANCED EFFICIENCY
Provided herein is an apparatus and a method useful for manufacturing MEMS devices. An aspect of the disclosed apparatus provides a substrate comprising an etchable material exposed to a solid-state etchant, wherein the substrate and the solid-state etchant are disposed in an etching chamber. In some embodiments, the solid state etchant is moved into close proximity to the substrate. In other embodiments, a configurable partition is between the substrate and the solid-state etchant is opened. The solid-state etchant forms a gas-phase etchant suitable for etching the etchable material. In some preferred embodiments, the solid-state etchant is solid xenon difluoride. The apparatus and method are advantageously used in performing a release etch in the fabrication of optical modulators.
1 . A method for fabricating a microelectromechanical systems device comprising:
disposing within an etching chamber a substrate comprising an etchable material, and
disposing within the etching chamber a solid etchant, wherein the solid etchant forms a gas-phase etchant capable of etching the etchable material.
2 . The method of claim 1 , wherein the microelectromechanical systems device is an optical modulator.
3 . The method of claim 1 , wherein the solid etchant is solid xenon difluoride.
4 . The method of claim 3 , further comprising:
disposing the substrate on a support; and
positioning the support and the solid xenon difluoride such that the support and the solid xenon difluoride are less than about 10 cm apart.
5 . The method of claim 1 , wherein the etchable material comprises molybdenum.
6 . The method of claim 1 , wherein the etchable material comprises silicon.
7 . A method for fabricating a microelectromechanical systems device comprising:
disposing a substrate within an etching chamber;
extending an etchant module into the etching chamber, wherein
a solid etchant is supported on the etchant module, and
the solid etchant forms a gas-phase etchant capable of etching a material on the substrate; and
allowing the gas-phase etchant to etch the material.
8 . The method of claim 7 , wherein the microelectromechanical systems device is an optical modulator.
9 . The method of claim 7 , wherein the solid etchant is solid xenon difluoride.
10 . The method of claim 7 , wherein the material on the substrate comprises molybdenum or silicon.
11 . The method of claim 7 , wherein extending the etchant module comprises positioning the etchant module such that a distance between the etchant module and the substrate is not more than 10 cm.
12 . A method for fabricating a microelectromechanical systems device comprising:
providing solid xenon difluoride within an etch chamber;
supporting a substrate comprising an etchable material within the etch chamber; and
etching the etchable material from the substrate with a vapor generated by the solid xenon difluoride.
13 . The method of claim 12 , wherein the microelectromechanical systems device is an optical modulator.
14 . The method of claim 12 , wherein the etchable material comprises molybdenum or silicon.
15 . The method of claim 12 , further comprising positioning the substrate and the solid xenon difluoride such that the substrate and the solid xenon difluoride are less than about 10 cm apart.
16 . A method for fabricating a microelectromechanical systems device comprising:
supporting a substrate comprising an etchable material within the etch chamber; and
positioning solid xenon difluoride sufficiently proximate to the substrate such that a vapor formed by the solid xenon difluoride etches the etchable material, wherein the substrate and the solid xenon difluoride are less than about 10 cm apart.
17 . The method of claim 16 , wherein the microelectromechanical systems device is an optical modulator.
18 . The method of claim 16 , wherein the etchable material comprises molybdenum or silicon.