Morphology and Spectroscopy of Nanoscale Regions using X-Rays Generated by Laser Produced Plasma
A system and method is disclosed for generation of a nanoplasma and/or nanofluorescence. The system includes an emissions source of soft x-rays. The emissions source can include a laser system as an energy source and target material that acts as a radiation source when illuminated by the laser system. The system further includes focusing optics particularly suited for manipulation of wavelengths associated with x-rays. The focusing optics can focus the x-rays onto a desired target so that a nanoplasma or nanofluorescent spot can be formed to have a diameter of less than 200 nm. Radiation from the nanoplasma or nanofluorescent spot can be examined, for example using a spectrometer, in order to perform a highly-selective material analysis of the desired target. Other applications include using the nanoplasma for nanoablation and/or nanodeposition processes.
1 . A nanoplasma-generating device, comprising:
an emissions source that includes a short-pulse laser system and a radiation source, the laser system operable to generate a laser pulse having an energy density sufficient to form a point plasma at the radiation source that emits short-wavelength radiation; and
a focusing optic for receiving the short-wavelength radiation from the radiation source and focusing the radiation onto a target to form a nanoplasma.
2 . A device according to claim 1 , wherein said short-wavelength radiation has a wavelength in a range of 0.5 nm to 15 nm.
3 . A device according to claim 1 , wherein said focusing optic includes at least one Bragg multilayer coating.
4 . A device according to claim 1 , wherein said focusing optic includes at least one of a grazing incidence optical element and a diffractive optical element.
5 . A device according to claim 1 , wherein said focusing optic is for focusing the radiation onto the target such that the nanoplasma has a diameter of less than 200 nm.
6 . A device according to claim 1 , further comprising a positioning stage for positioning the target.
7 . A device according to claim 1 , wherein the laser pulse generated by the short-pulse laser system has a pulse width of less than one nanosecond and an energy of at least 200 mJ.
8 . A device according to claim 7 , wherein the radiation source comprises a metallic tape.
9 . A device according to claim 8 , wherein the focusing optic comprises a first relay condenser, an intermediate aperture, and a second relay condenser, wherein the first relay condenser is operable to receive the short-wavelength radiation from the radiation source and focus the radiation onto the intermediate aperture, and wherein the intermediate aperture permits the passage of the short-wavelength radiation to the second relay condenser, and wherein the second relay condenser is operable to receive the short-wavelength radiation from the intermediate aperture and focus the radiation onto the target.
10 . A device according to claim 1 , further comprising an analyzing assembly for performing a spectroscopic analysis of the target based on radiation emitted from the nanoplasma.
11 . A device according to claim 1 , wherein the nanoplasma causes ablation of material of the target.
12 . A device according to claim 1 , wherein a reactive gas is provided in the vicinity of the target, wherein the nanoplasma causes reaction of the reactive gas so that a resultant is produced and deposited on the target.
13 . A method for generating a nanoplasma comprising:
providing a laser pulse having an energy density sufficient to form a point plasma at a radiation source so as to generate short-wavelength radiation;
generating a nanoplasma by focusing the short-wavelength radiation onto a spot on a target.
14 . A method according to claim 13 , wherein said short-wavelength radiation has a wavelength in a range of 0.5 nm to 15 nm.
15 . A method according to claim 13 , wherein step of focusing is performed at least in part by an optical element having a Bragg multilayer coating.
16 . A method according to claim 13 , wherein said step of focusing is performed at least in part by at least one of a grazing incidence optical element and a diffractive optical element.
17 . A method according to claim 13 , wherein the nanoplasma has a diameter of less than 200 nm.
18 . A method according to claim 13 , further comprising a step of controlling a positioning stage in order to position the target.
19 . A method according to claim 13 , wherein the laser pulse has a pulse width of less than one nanosecond and an energy of at least 200 mJ.
20 . A method according to claim 19 , wherein the radiation source comprises a metallic tape.
21 . A method according to claim 20 , wherein the focusing of the short-wavelength radiation comprises:
receiving short-wavelength radiation from the radiation source at a relay condenser and focusing the radiation onto an intermediate aperture;
permitting the passage of the short-wavelength radiation through the intermediate aperture to a second relay condenser; and
receiving the short-wavelength radiation at the second relay condenser and focusing the radiation onto the spot on the target.
22 . A method according to claim 13 , further comprising performing a spectroscopic analysis of the target based on radiation emitted from the nanoplasma.
23 . A method according to claim 13 , wherein the generating of the nanoplasma includes ablating an amount of material from the target.
24 . A method according to claim 13 , further comprising providing a reactive gas in the vicinity of the target, wherein the generating of the nanoplasma includes causing reaction of the reactive gas so that a resultant is produced and deposited on the target.
25 . A nanofluorescence-generating device, comprising:
a short-pulse laser system operable to generate a laser pulse having an energy density sufficient to form a point plasma at a radiation source that emits short-wavelength radiation; and
a focusing optic operable to receive the short-wavelength radiation from the radiation source and focus the radiation onto a target so that a nanofluorescent spot is formed.
26 . A device according to claim 25 , wherein the laser pulse has a pulse width of less than one nanosecond and an energy of at least 200 mJ.
27 . A device according to claim 26 , wherein the radiation source comprises a metallic microtarget.
28 . A device according to claim 27 , wherein the focusing optic comprises:
a first parabolic reflector having a focal point substantially aligned with the radiation source, the first parabolic reflector comprising multilayer interference films operable to reflect and substantially collimate short-wavelength radiation emitted by the radiation source; and
a second parabolic reflector having a focal point substantially aligned with the target, the parabolic reflector comprising multilayer interference films operable to reflect and focus short-wavelength radiation onto a spot on the target having a diameter less than 200 nm so as to generate a nanofluorescent spot.
29 . A device according to claim 25 , further comprising an analyzing assembly for performing a spectroscopic analysis of the target based on radiation from the nanofluorescent spot.
30 . A device according to claim 25 , wherein the nanofluorescent spot has a diameter of less than 200 nm.
31 . A method for generating a nanofluorescent spot comprising:
providing a laser pulse having an energy density sufficient to form a point plasma at a radiation source that emits short-wavelength radiation; and
generating a nanofluorescent spot by focusing the short-wavelength radiation onto a spot on a target.
32 . A method according to claim 31 , wherein the laser pulse has a pulse width of less than one nanosecond and an energy of at least 200 mJ.
33 . A method according to claim 32 , wherein the generating of the short-wavelength radiation source comprises a metallic microtarget.
34 . A method according to claim 33 , wherein the focusing of the radiation comprises:
reflecting and collimating the short-wavelength radiation emitted by the radiation source with a first parabolic reflector having a focal point substantially aligned with the radiation source, the first parabolic reflector comprising multilayer interference films; and
reflecting and focusing the short-wavelength radiation onto the spot on the target with a second parabolic reflector having a focal point substantially aligned with the target, the second parabolic reflector comprising multilayer interference films.
35 . A method according to claim 31 , further comprising performing a spectroscopic analysis of the target based on radiation from the nanofluorescent spot.
36 . A method according to claim 31 , wherein the nanofluorescent spot has a diameter of less than 200 nm.