P506 – Exit Slit Unit HINESS HEPS IHEP CAS
Application
Exit slit unit for soft X-ray radiation
Year of delivery
2024
Installation site
HINESS beamline at High Energy Photon Source, Institute of High Energy Physics, China
Design Features
-
Double slit mechanism – vertically and horizontally defining slits.
- Motorized and encoded slits opening, symmetric opening, non-linear opening characteristics.
- OFHC slit blades.
-
Electrical isolation of horizontally defining slit blades.
- Isolated bias plate with fluorescing screen.
- Manually retractable photodiode.
-
EtherCAT based motion control system, synchronized encoder readout, software with server-client architecture, TCP-IP protocol, EPICS interface.
- Adjustable support structure.
Performance Features
- Precision and slit opening repeatability smaller than 150 nm.
- Parallelism smaller than 0.55 µm over 10 mm edge length.
- Straightness smaller than 0.2 µm over 10 mm edge length.
- Very small deviation 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
Horizontally defining slit (HDS)
Slit blades
Material
OFHC
Straightness
< 0.50 µm over 25 mm (1σ)
Parallelism
-0.01 μm /mm
(ca. 50 μm slit opening)
0.002 μm /mm
(ca. 100 μm slit opening)
0.05 μm /mm
(ca. 150 μm slit opening)
Slit opening
Range
1.70 µm to 4.10 mm
Repeatability
0.10 μm at ca. 50 μm slit opening
0.09 μm at ca. 100 μm slit opening
0.08 μm at ca. 150 μm slit opening
Resolution (design value)
0.00156 µm /motor fine step
(1/64, recommended)
0.05 µm /encoder count
Vertically defining slit (VDS)
Slit blades
Material
OFHC
Straightness
< 0.30 µm over 30 mm (1σ)
Parallelism
-0.04 μm / mm
(ca. 53 μm slit opening)
-0.02 μm /mm
(ca. 152 μm slit opening)
Slit opening
Range
2 µm to 4 mm
Repeatability
0.04 μm at ca. 23 μm slit opening
0.06 μm at ca. 52 μm slit opening
0.04 μm at ca. 151 μm slit opening
Resolution (design value)
0.00156 µm /motor fine step
(1/64, 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)
Residual gas analysis
