P394 – Exit Slit Unit ESM (A-branch) NSLS-II
Application
Exit slit unit for soft X-ray synchrotron radiation
Year of delivery
2015
Installation site
ESM beamline at synchrotron radiation source NSLS-II, USA
Design Features
-
Double slit mechanism – vertically and horizontally defining slits.
-
Motorized and encoded slits opening, symmetric opening, non-linear opening characteristics.
- OFHC slit blades.
- Manual slit unit translation along beam axis.
- Isolated bias plate with phosphorus screen.
- Photodiode behind vertically defining slit.
- Adjustable support structure.
Performance Features
- Precision and slit opening repeatability smaller than 100 nm.
- Parallelism smaller than 0.6 µm over 10 mm edge length.
- Straightness smaller than 0.5 µm over 10 mm edgle length.
- Very small deviation (submicrometer) of the slit opening calibration curve from the theoretical non-linear slit opening function.
Outer Dimensions
Technical specifications and performance values
General
Vacuum chamber
Chamber type
cylindrical, horizontal axis
Main flanges
DN160CF cluster flanges
Material
1.4301
Base pressure
10-10 mbar range
Translation along beam axis
(manual)
Range
± 100 mm
Support structure
adjustment ranges
Height
± 5 mm
Lateral
± 5 mm
Longitudinal
± 5 mm
Yaw
± 1°
Horizontally defining slit (HDS)
Slit blades
Material
OFHC
Straightness
< 0.10 µm over 10 mm (1σ)
Parallelism
0.03 µm /mm
(10 µm slit opening)
0.01 µm /mm
(25 µm slit opening)
-0.01 µm /mm
(50 µm slit opening)
Slit opening
Range
4 µm to 9.7 mm
Repeatability
± 0.10 µm
(up to 370 µm slit opening)
Resolution (design value)
0.006 µm /motor fine step
(1/16, recommended)
0.05 µm /encoder count
Vertically defining slit (VDS)
Slit blades
Material
OFHC
Straightness
< 0.10 µm over 10 mm (1σ)
Parallelism
-0.02 µm /mm
(15 µm slit opening)
-0.04 µm /mm
(25 µm slit opening)
-0.05 µm /mm
(50 µm slit opening)
Slit opening
Range
3 µm to 10 mm
Repeatability
± 0.02 µm
(up to 355 µm slit opening)
Resolution (design value)
0.006 µm /motor fine step
(1/16, recommended)
0.05 µm /encoder count
Performance Test Results
Slit width calibration (HDS)
Slit opening repeatability (HDS)
Slit blades parallelism (HDS)
Slit blades parallelism (HDS)
Slit blades parallelism (HDS)
Slit width calibration (VDS)
Slit opening repeatability (VDS)
Slit blades parallelism (VDS)
Slit blades parallelism (VDS)
Slit blades parallelism (VDS)
