System and method for measuring a sample by x-ray reflectance scatterometry
A system and method for measuring a sample by X-ray reflectance scatterometry. The method may include impinging an incident X-ray beam on a sample having a periodic structure to generate a scattered X-ray beam, the incident X-ray beam simultaneously providing a plurality of incident angles and a plurality of azimuthal angles; and collecting at least a portion of the scattered X-ray beam.
1. A method of measuring a sample by X-ray reflectance scatterometry, the method comprising:
directing an X-ray generated within a first sub-chamber through a X-ray transmissive region that is formed between the first-sub chamber and a second sub-chamber towards a sample having a periodic structure and located within a second sub-chamber to generate a scattered X-ray beam, the incident X-ray beam simultaneously providing a plurality of incident angles and a plurality of azimuthal angles;
suppressing, by a magnetic electron suppression device that is positioned within the first sub-chamber, electrons emitted, in addition to the X-ray, from the X-ray source as a result of illumination of the X-ray source with an electron beam from an electron gun;
and
collecting at least a portion of the scattered X-ray beam.
2. A system for measuring a sample by X-ray reflectance scatterometry, the system comprising:
a first sub-chamber;
a second sub-chamber;
an X-ray source that is located within the first sub-chamber and is configured to generate an X-ray beam that passes through a X-ray transmissive region formed between the first-sub chamber and the second sub-chamber;
a sample holder located within the second-sub-chamber and is configured to position a sample having a periodic structure;
optics positioned between the X-ray source and the sample holder, the optics is configured to focus the X-ray beam to provide an incident X-ray beam to the sample, the incident X-ray beam simultaneously having a plurality of incident angles and a plurality of azimuthal angles;
a magnetic electron suppression device positioned within the first sub-chamber; wherein the magnetic electron suppression device is configured to suppress electrons emitted, in addition to the X-ray, from the X-ray source as a result of illumination of the X-ray source with an electron beam from an electron gun; and
a detector that is configured to collect at least a portion of a scattered X-ray beam from the sample.
3. The system according to claim 2 wherein the X-ray transmissive region is a window.
4. The system according to claim 2 , wherein the magnetic electron suppression device is positioned above the X-ray beam.
5. The system according to claim 2 , wherein the magnetic electron suppression device is in contact with the electron gun.
6. The system according to claim 2 , wherein at least a part of the magnetic electron suppression device is positioned above a top of the X-ray transmissive region.
7. The system according to claim 2 , wherein the electron gun is configured to illuminate a X-ray source that is an anode, wherein the anode is configured to emit radiation towards the second sub-chamber.
8. The system according to claim 7 wherein the anode comprises at least one material out of carbon, Rhodium and molybdenum.
9. The system according to claim 2 wherein the electron gun comprises at least a portion located within the first sub-chamber.
10. The system according to claim 2 wherein the detector is a two-dimensional detector.
11. The system according to claim 2 wherein the detector is a scanning slit detector.
12. The system according to claim 2 wherein the optics comprises a monochromator.
13. The system according to claim 2 wherein the optics comprises a toroidal multilayer monochromator.
14. The system according to claim 2 wherein the sample holder is a rotatable sample holder.
15. The system according to claim 2 wherein the X-ray beam has an energy that does not exceed 1 keV.
16. The system according to claim 2 wherein the sample comprises a periodic structure; wherein the optics is configured to provide the incident X-ray beam to the periodic structure; wherein the at least portion of the scattered X-ray beam from the sample comprises at least a portion of scattered X-ray beam from the periodic structure.
17. The system according to claim 16 comprising a processor that is configured to estimate a shape of the periodic structure by inversion of scattering solutions relative to the at least portion of the scattered X-ray beam from the periodic structure.
18. The system according to claim 2 comprising a processor; wherein the incident X-ray beam is collimated; and wherein the processor is configured to analyze multiple orders of the at least portion of the scattered X-ray beam from the sample.
19. The system according to claim 2 wherein the magnetic electron suppression device is mechanically coupled to a top wall of the second sub-chamber via a mechanical interface.