System and method for wafer-scale fabrication of free standing mechanical and photonic structures by ion beam etching
A method for fabrication of free standing mechanical and photonic structures is presented. A resist mask is applied to a bulk substrate. The bulk substrate is attached to a movable platform. The bulk substrate is exposed to an ion stream produced by a reactive ion beam etching source. The platform is moved relative to the ion stream to facilitate undercutting a portion of the bulk substrate otherwise shielded by the mask.
1. A method for simultaneous fabrication of multiple free standing mechanical and photonic structures, comprising the steps of:
applying a resist mask to a bulk substrate;
attaching the bulk substrate to a movable platform;
forming with a collimated reactive ion beam etching (RIBE) source a RIBE ion stream comprising ions that chemically react with the bulk substrate material;
collimating the RIBE ion stream via ion optics;
exposing the bulk substrate to the RIBE ion stream directed at the movable platform; and
moving the platform relative to the ion stream to facilitate undercutting a portion of the bulk substrate otherwise shielded by the mask to simultaneously mill multiple nanostructures with the RIBE ion stream.
2. The method of claim 1 , wherein the bulk substrate comprises diamond.
3. The method of claim 1 , wherein moving the platform comprises laterally displacing the platform in a plane substantially parallel to the ion stream.
4. The method of claim 1 , wherein moving the platform comprises tilting the platform relative to a plane substantially parallel to the ion stream.
5. The method of claim 4 , wherein a tilt angle of the platform relative to the ion stream is in the range of 10 degrees to 80 degrees.
6. The method of claim 4 , wherein moving the platform further comprises rotating the platform relative to the ion stream.
7. The method of claim 3 , further comprising the step of adjusting the ion stream according to the orientation and/or position of the platform relative to the ion stream.
8. The method of claim 1 , wherein the ion stream comprises oxygen ions, and the substrate comprises diamond.
9. The method of claim 1 , wherein the ion stream comprises fluorine ions, and the substrate comprises quartz.
10. The method according to claim 1 , wherein the ion stream produced by the collimated reactive ion beam etching source comprises a beam diameter in the range of 4 cm to 22 cm.
11. The method according to claim 6 , wherein the ion stream produced by the collimated reactive ion beam etching source comprises a beam diameter in the range of 4 cm to 22 cm.
12. A method for simultaneous fabrication of multiple free standing mechanical and photonic structures, comprising the steps of:
applying a resist mask to a bulk substrate;
attaching the bulk substrate to a movable platform;
forming with a collimated reactive ion beam etching (RIBE) source a RIBE ion stream comprising ions that chemically react with the bulk substrate material;
collimating the RIBE ion stream via ion optics;
exposing the bulk substrate to the RIBE ion stream directed at the movable platform;
top down etching the substrate, wherein the ion beam is perpendicular to a top surface of the substrate; and
moving the platform relative to the ion stream to facilitate undercutting a portion of the bulk substrate otherwise shielded by the mask to simultaneously mill multiple nanostructures with the RIBE ion stream.
13. The method of claim 12 , wherein moving the platform comprises laterally displacing the platform in a plane substantially parallel to the ion stream and tilting the platform relative to a plane substantially horizontal to the ion stream in the range of 10 degrees to 80 degrees.
14. The method of claim 13 , wherein moving the platform further comprises rotating the platform relative to the ion stream.