1. A filter media comprising a fine fiber layer and a filtration substrate layer, the substrate layer comprising a synthetic polymer, the substrate having a thickness of 25 to 800 microns and a basis weight of about 8 to 200 gm-m\u22122, the fine fiber layer having a thickness no greater than 30 microns and a basis weight of about 0.5 to 50 g-m\u22122, the fine fiber comprising a fiber size of about 0.01 to 2 micron.
2. The media of claim 1 wherein after exposure to air at 140\xb0 F. and 100% relative humidity for 16 hours at least 50% of the fine fiber remains substantially unchanged for filtration.
3. The media of claim 2 wherein a temperature of 160\xb0 F. is used for 3 hours.
4. The media of claim 1 wherein the fine fiber has a diameter of 0.01 to 0.5 microns.
5. The media of claim 1 wherein the fine fiber has a diameter of 0.1 to 0.2 microns.
6. The media of claim 1 wherein the substrate comprises a spun bonded fabric.
7. The media of claim 1 wherein the substrate comprises a woven or non-woven fabric having a basis weight of 0.5 to 150 gm-m\u22122.
8. The media of claim 1 wherein the substrate comprises a polyolefin.
9. The media of claim 8 wherein the substrate comprises a polyethylene.
10. The media of claim 8 wherein the substrate comprises a polypropylene.
11. The media of claim 6 wherein the spun bonded fabric comprises polyolefin spun bonded fabric.
12. The media of claim 11 wherein the polyolefin spun bonded fabric comprises polypropylene spun bonded fabric.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A system, comprising:
an objective lens configured to focus a charged particle beam in an object plane;
a first condenser lens disposed in a beam path of the charged particle beam upstream of the objective lens;
a deflector disposed in the beam path between the first condenser lens and the objective lens, the deflector configured to change an angle of incidence of the charged particle beam in an object plane; and
an aberration corrector disposed in the beam path between the deflector and the objective lens, the aberration corrector configured to compensate aberrations introduced by the objective lens,
wherein the aberration corrector is configured to not compensate aberrations introduced by the first condenser lens, and the system is a charged particle beam column.
2. The system according to claim 1, further comprising a second condenser lens disposed in the beam path between the deflector and the objective lens, wherein the aberration corrector is configured to correct aberrations introduced by the second condenser lens.
3. The system according to claim 2, further comprising a beam scanner disposed in the beam path between the aberration corrector and the object plane, wherein the beam scanner is configured to scan a location of incidence of the charged particle beam across the object plane.
4. The system according to claim 3, wherein the aberration corrector comprises a plurality of multipole lens elements.
5. The system according to claim 3, wherein the aberration corrector comprises a mirror configured to reflect the charged particle beam.
6. The system according to claim 2, wherein the aberration corrector comprises a plurality of multipole lens elements.
7. The system according to claim 2, wherein the aberration corrector comprises a mirror configured to reflect the charged particle beam.
8. The system according to claim 1, further comprising a beam scanner disposed in the beam path between the aberration corrector and the object plane, wherein the beam scanner is configured to scan a location of incidence of the charged particle beam across the object plane.
9. The system according to claim 8, wherein the aberration corrector comprises a plurality of multipole lens elements.
10. The system according to claim 8, wherein the aberration corrector comprises a mirror configured to reflect the charged particle beam.
11. The system according to claim 1, wherein the aberration corrector comprises a plurality of multipole lens elements.
12. The system according to claim 1, wherein the aberration corrector comprises a mirror configured to reflect the charged particle beam.
13. The system according to claim 1, further comprising a charged particle beam source upstream, wherein the first condenser lens disposed in the beam path between the objective lens and the charged particle beam source.
14. A method, comprising:
condensing a charged particle beam while introducing first aberrations into the charged particle beam to provide a first condensed charged particle beam;
deflecting the condensed charged particle beam to provide a deflected charged particle beam;
focusing the deflected charged particle beam on a specimen while introducing second aberrations into the deflected charged particle beam; and
compensating the second aberrations while leaving the first aberrations uncompensated to provide a compensated charged particle beam.
15. The method according to claim 14, further comprising:
further condensing the deflected charged particle beam while introducing third aberrations on the beam; and
compensating the third aberrations.
16. The method according to claim 15, further comprising scanning a location of incidence of the compensated charged particle beam across the specimen.
17. The method according to claim 14, further comprising scanning a location of incidence of the compensated charged particle beam across the specimen.
18. A system, comprising:
an objective lens configured to focus a charged particle beam in an object plane;
a deflector disposed in a beam path of the charged particle beam upstream of the objective lens; and
an aberration corrector disposed in the beam path between the deflector and the objective lens,
wherein the aberration corrector is configured to compensate aberrations introduced by components located in the beam path downstream of the deflector without compensating aberrations introduced by components located in the beam path upstream of the deflector, and the system is a charged particle beam column.
19. The system according to claim 18, further comprising a first condenser lens disposed in the beam path upstream of the deflector.
20. The system according to claim 18, further comprising a charged particle beam source, wherein the deflector is disposed in the beam path between the objective lens and the charged particle beam source.