PLASMON HEAD WITH HYDROSTATIC GAS BEARING FOR NEAR FIELD PHOTOLITHOGRAPHY
A low-cost approach to near field nano-scale photolithography using a plasmonic head with hydrostatic gas bearings. The hydrostatic gas bearing flies the plasmonic head at less than 100 nm, and more preferably less than 50 nm, above the photo-resist without the need to spin the substrate. The plasmonic head concentrates short-wavelength surface plasmons into about sub-100 nm regions on the photo-resist and can pattern features of about 80 nm or less.
1 . A photolithography system for creating a pattern of exposed regions in a photo-resist layer on substrate, the photolithography system comprising:
a head suspension assembly comprising a load beam having a flexure at a distal end, and a plurality of channels;
a covering layer extending over the channels to form gas conduits;
a slider comprising a first surface attached to the flexure and a second surface facing the substrate, the first surface of the slider including a plurality of ports fluidly coupled to the conduits, the ports extending through the slider and exiting through holes in at least one air bearing surface located on the second surface;
a near field assembly on the slider that emits radiation onto at least one region of the photo-resist in response to incident radiation, the region having a maximum dimension of less than about 100 nanometers;
a laser assembly adapted to supply the incident radiation;
a source of pressurized gas delivered to the conduits to maintain a clearance between the near field assembly and the photo-resist layer of less than about 100 nanometers; and
a controller adapted to synchronize activation of the laser assembly with the position of the substrate relative to the near field assembly.
2 . The photolithography system of claim 1 comprising:
a base plate at a proximal end of the head suspension; and
a flexible conduit fluidly coupling the conduits on the head suspension to a source of pressurized gas.
3 . The photolithography system of claim 1 wherein the near field assembly comprises a near field transducer located on an edge of the slider.
4 . The photolithography system of claim 1 comprising an aperture structure extending from the first surface to the second surface of the slider, the aperture structure comprising a material substantially reflective to the incident radiation and an aperture having a cross-sectional size less than a wavelength of the incident radiation.
5 . The photolithography system of claim 1 wherein the substrate is one or more of flexible, rigid, planar, non-planar, or cylindrical.
6 . The photolithography system of claim 1 wherein the laser assembly supplies radiation at a first wavelength and the near field assembly emits radiation at a second shorter wavelength in response to incident radiation.
7 . The photolithography system of claim 1 wherein the region of radiation emitted onto the photo-resist has a maximum dimension of less than about 80 nanometers.
8 . The photolithography system of claim 1 wherein the region of radiation emitted onto the photo-resist has a maximum dimension of less than about 60 nanometers.
9 . The photolithography system of claim 1 wherein the pattern comprises features having a size less than about a wavelength of the incident radiation.
10 . The photolithography system of claim 1 wherein the pattern comprises features having a size less than about 50% of a wavelength of the incident radiation.
11 . The photolithography system of claim 1 wherein the pattern comprises features having a size less than about 20% of a wavelength of the incident radiation.
12 . The photolithography system of claim 1 comprising a sensor monitoring the clearance between the near field assembly and the photo-resist layer.
13 . The photolithography system of claim 1 wherein the clearance between the near field assembly and the photo-resist layer of less than about 50 nanometers.
14 . The photolithography system of claim 1 wherein the clearance between the near field assembly and the photo-resist layer of less than about 20 nanometers.
15 . A plasmonic head for creating a pattern of exposed regions in a photo-resist layer on substrate, the plasmonic head comprising:
a head suspension assembly comprising a load beam having a flexure at a distal end, and a plurality of channels;
a covering layer extending over the channels to form gas conduits;
a slider comprising a first surface attached to the flexure and a second surface facing the substrate, the first surface of the slider including a plurality of ports fluidly coupled to the gas conduits, the ports extending through the slider and exiting through holes in at least one air bearing surface located on the second surface, the ports adapted to emit a gas to maintain a clearance between the second surface and the photo-resist layer of less than about 100 nanometers; and
a near field assembly on the slider that emits radiation onto a region of the photo-resist in response to incident radiation with a maximum dimension of less than about 100 nanometers.
16 . A method for forming a pattern in photo-resist layer on a substrate using a photolithography system, the method comprising the step of:
delivering a pressurized gas through gas conduits in a head suspension to ports on a slider;
ejecting the pressurized gas from the ports in the slider to create a hydrostatic gas bearing with a clearance between a near field assembly and a photo-resist layer of less than about 100 nanometers;
directing incident radiation from a laser assembly to the near field assembly;
emitting a region of radiation from the near field assembly onto the photo-resist in response to the incident radiation with a maximum dimension of less than about 100 nanometers; and
synchronizing activation of the laser assembly with a position the substrate relative to the near field assembly to form the pattern.