Technical Specifications of VLS

2 optical element of the beamline is a toroidal mirror M1 that focuses the beam on to the entrance slit S1. The low energy radiation is reflected by t...

0 downloads 98 Views 498KB Size
Technical Specifications of VLS- Plane Gratings for ARPES and XMCD beamlines Item:VLS- Plane Gratings for ARPES and XMCD beamlines Quantity:

5 (Five)

Important note to bidders:  

The price of the each grating shall be quoted separately A bidder may bid for one or more gratings mentioned in the tender

Bid evaluation criteria: 

The price of the each grating will be compared separately.



The supplier should be ready to provide one or more number of gratings pout of

the five gratings set.

1. Scope of the Tender The scope of the tender is the supply of five Varied Line Spacing Plane Gratings (VLS-PG) that will be used for the Angle Resolved Photo-Electron Spectroscopy (ARPES) and X-ray Magnetic Circular Dichroism (XMCD) beamlines on Indus-2 synchrotron source. These beamlines are proposed to be installed on a planar permanent magnet and APPLE-II type undulators, respectively. 2. Bidder qualification i) The supplier shall be an original manufacturer (OEM) of the item, or an authorized supplier of the OEM, or standard synchrotron beamline component supplier. ii) The company should have supplied at least six soft x-ray gratings in the past two years for synchrotron beamlines. The list of beamlines where similar gratings have been supplied by the company must be provided with the offer. iii) The supplier should have the facility for the metrology of these gratings. The details of the instruments available with the supplier for this purpose shall be mentioned in the offer.

3. Beamline details 3.1 ARPES beamline: A schematic optical design of the beamline is shown in Fig. 1. The monochromator design is a constant included angle, variable line spacing grating based system. The first

1

optical element of the beamline is a toroidal mirror M1 that focuses the beam on to the entrance slit S1. The low energy radiation is reflected by the mirror SM2 and falls on the grating. The higher energy radiation is reflected by the mirror SM1 on to the grating. The gratings proposed to be purchased for this beamline are named G1A, G2A, and G3A. G1A operates in the energy range: 80 eV to 270 eV, G2A operates in the energy range: 215 eV to 500 eV, and G3A operates in the energy range: 430 eV to 1000 eV. The gratings are rotated for wavelength selection and the mirrors are kept fixed. The gratings focus the xrays on the exit slit S2. The x-rays are finally focused on the sample using the toroidal mirror M2.

Side view: VLS-PG S1 S2 Toroidal Mirror, M1

SM1

SM2 Sample

Toroidal Mirror, M2

Top view:

18500 M1

9000

S1 3400.3 (4000)

SM1 997.6

VLS-PG 3600

S2 1500

1500

(SM2) (400)

Figure 1. Optical layout of ARPES beamline (Not to scale). The circled part shows the position of the monochromator where the gratings will be placed. (all distances are given in mm)

2

3.2 XMCD beamline: A schematic optical design of the beamline is shown in Fig. 2. The beamline is based on a Variable Included Angle Variable Line Spacing Plane Grating (VLS-PG) monochromator design. In this beamline, the first optical component is a water cooled toroidal mirror (TM1) that focuses the SR beam in the sagittal direction on to the water cooled slit S1 of the monochromator. The second optical element, a spherical mirror SM, which remains fixed during the energy scan, and focuses the beam behind the VLS-PG . A long plane mirror between the spherical mirror and the grating provides the variable included angles to the grating. The gratings proposed to be purchased for this beamline are G1X and G2X. Grating G1X operates in the energy range: 300 eV to 1,000 eV and the grating G2X operates in the energy range: 600 eV to 2,000 eV. The gratings focus the x-rays on the exit slit S2. The x-ray is finally focused on the sample using the toroidal mirror M2. The plane mirror and the grating movements are used to select the energy. Side view: S1

VLS-PG

SM

S2 Expt-1

TM1

Expt-2

PM M1 & M2

Top view:

18500

TM1

8000

S1

4086.6 0

SM

PM 486.6

VLS-PG 3600 S2 1500 M1 1500 & M2

Figure 2. Optical layout of XMCD beamline (Not to scale). The circled part shows the position of the monochromator where the gratings will be placed. (all distances are given in mm)

3

1200

4. Technical Specifications In this section, the detail technical specifications of the gratings are described. The groove density ( in units of lines/mm) variation of the VLS-PG is defined by the following equation for all the gratings: N(w) = No (1+a1w+ a2w2+ a3w3+…) where “No” is the groove density at the centre of the grating, and “w” is the distance measured from the centre of the grating along the meridional axis. All the gratings will be mounted in the inverted geometry, i.e., the grating rulings are facing downwards. Detail specifications of the gratings are given in the following Tables. Table 1: Technical specification of the grating (G1A) for the ARPES beamline, for the 80 eV to 270 eV energy range. Grating G1A Shape Planar Grating type Laminar (VLS) Geometrical dimension 130 × 30 mm2 (± 0.1 mm in both dim.) Optical dimension 120× 20 mm2 (± 1 mm in both dim.) Thickness 40 ± 0.5 mm Substrate material Silicon RMS slope error of the starting Meridional : ≤ 0.15 arcsec substrate Sagittal: ≤ 1.75 arcsec RMS substrate roughness ≤ 0.3 nm 1 Coating material Au or Pt Coating thickness 30 ± 10 nm Groove density at the center of 770 lines/mm ± 2 lines/mm the grating (No) Groove axis Perpendicular to the long axis (meridional axis) within ± 0.5o 2 3 Grating parameter G/L = 0.6 ± 25 % , GD = 19 ± 20% nm -4 -1 a1= - 5.52×10 mm (±1 %) Grating spacing parameters a2= 2.28 × 10-7 mm-2 (± 20%) The value of a3 for grating G1A is, -8.3 × 10-11 mm-3. The design value of a3 for the grating should be within ± 10% .

4

Table 2: Technical specification of the grating (G2A) for the ARPES beamline, for the 215 eV to 500 eV energy range. Grating Shape Grating type Geometrical dimension Optical dimension Thickness Substrate material RMS slope error of the starting substrate RMS substrate roughness Coating material1 Coating thickness Groove density at the center of the grating (No) Groove axis

G2A Planar Laminar (VLS) 130 × 30 mm2 (± 0.1 mm in both dim.) 120 × 20 mm2 (± 1 mm in both dim.) 40 ±0.5 mm Silicon Meridional : ≤ 0.15 arcsec Sagittal: ≤ 3 arcsec ≤ 0.3 nm Au or Pt 30 ± 10 nm 700 lines/mm ± 2 lines/mm

Perpendicular to the long axis (meridional axis) within ± 0.5o 2 3 Grating parameters G/L = 0.6 ± 25% , GD = 17 ± 20% nm Grating spacing parameters a1= - 5.54×10-4 mm-1 (±1 %) a2= 2.30 × 10-7 mm-2 (± 20%) The value of a3 for grating G2A is, - 8.5 × 10-11 mm-3. The design value of a3 for the grating should be within ± 10% . Table 3: Technical specification of the grating (G3A) for the ARPES beamline, for the 430 eV to 1,000 eV energy range. Grating Shape Grating type Geometrical dimension Optical dimension Thickness Substrate material RMS slope error of the starting substrate RMS substrate roughness Coating material1 Coating thickness Groove density at the center of the grating (No) Groove axis

G3A Planar Laminar or blazed (VLS) 130 × 30 mm2 (± 0.1 mm in both dim.) 120 × 20 mm2 (± 1 mm in both dim.) 40 ± 0.5 mm Silicon Meridional : ≤ 0.15 arcsec Sagittal: ≤ 3 arcsec ≤ 0.3 nm Au or Pt 30 ± 10 nm 1400 lines/mm ± 2 lines/mm

Perpendicular to the long axis (meridional axis) within ± 0.5o 2 3 Grating parameters G/L = 0.6 ± 25 % , GD = 8 ± 25 % nm Grating spacing parameters a1= - 5.54×10-4 mm-1 (±1 %) a2= 2.30 × 10-7 mm-2 (± 20%) -11 -3 The value of a3 for grating G3A is, - 8.5 × 10 mm . The design value of a3 for the grating should be within ± 70% .

5

Table 4: Technical specification of the grating (G1X) for the XMCD beamline, for the 300 eV to 1,000 eV energy range. Grating G1X Shape Planar Grating type Laminar (VLS) Geometrical dimension 150 mm × 30 mm (± 0.1 mm in both dim.) Optical dimension 140 mm × 20 mm (± 1 mm in both dim.) Thickness 40 ± 0.5 mm Substrate material Silicon RMS slope error of the starting Meridional: ≤ 0.15 arcsec substrate Sagittal: ≤ 2.5 arcsec RMS substrate roughness ≤ 0.3 nm rms Coating material1 Au or Pt Coating thickness 30 ± 10 nm Groove density at the center of 900 lines/mm ± 2 lines/mm the grating (No) Groove axis Perpendicular to the long axis (meridional axis) within ±0.5o 2 Grating parameters G/L = 0.6± 25% ; 3GD = 11 ± 25% nm Grating spacing parameters

a1 = -5.55×10-4 mm-1 (± 2 %) a2 = 2.31×10-7 mm-2 (± 20 %)

The value of a3 for grating G1X is, - 8.5 × 10-11 mm-3. The design value of a3 for the grating should be within ± 40% . Table 5: Technical specification of the grating (G2X) for the XMCD beamline, for the 600 eV to 2,000 eV energy range. Grating G2X Shape Planar Grating type Laminar (VLS) Geometrical dimension 150 mm × 30 mm (± 0.1 mm in both dim.) Optical dimension 140 mm × 20 mm (± 1 mm in both dim.) Thickness 40 ± 0.5 mm Substrate material Silicon RMS slope error of the starting Meridional: ≤ 0.15 arcsec substrate Sagittal: ≤ 2.5 arcsec RMS substrate roughness ≤ 0.3 nm rms 1 Coating material Au or Pt Coating thickness 30 ± 10 nm Groove density at the center of 1800 lines/mm ± 2 lines/mm the grating (No) Groove axis Perpendicular to the long axis (meridional axis) within ±0.5o 2 Grating parameters G/L = 0.6± 33% ; 3GD = 6 ± 30% nm a1 = -5.55×10-4 mm-1 (± 1 %) a2 = 2.31×10-7 mm-2 (± 20 %) The value of a3 for grating G2X is, -8.5×10-11 mm-3. The design value of a3 for the grating should be within ± 40% . Grating spacing parameters

6

Points common to the Table 1 to 4 1

A Pt binding layer or any compatible binding layer to the energy range of operation of the

gratings shall be mentioned in the offer. The details of the binding layer and the material of the coating layer will be decided at the design stage. 2

G/L: Groove Width/ Groove Spacing

3

GD: Groove Depth

Common specifications for all the gratings: 5. Holding Mechanism The gratings are to be manufactured in such a way, that they can be firmly held in the respective grating holders in the monochromator. The preferred grating profile for holding is shown in Fig. 3. If the supplier wants to use any other profile to hold the grating, then it shall be mentioned in the quotation. Please note that the scheme and all the dimensions shown for the grooves at the bottom of the grating are tentative and will be decided at the time of the design review, after the order is placed.

Figure 3: A schematic layout of the preferred grating holder profile. The dimensions of the groove are tentative and will be decided at the design stage. All dimensions are in mm. Typical tolerance on groove width and height is ± 0.1 mm. All other dimensions and tolerances are as per the Tables 1 to 5. 6. Thermal Load and Cooling Mechanism The maximum thermal load on the gratings is 60 watt (0.15 W/mm2). A cooling mechanism (a tentative scheme is shown in Fig. 4) for the gratings will be a part of the monochromator. The side face of the gratings ( length x height) where the cooling copper block is held, should be polished to < 1 micron meter rms roughness. This tender only covers the supply of the gratings. The installation, mounting, and fixing of the gratings is not within the scope of the present tender.

7

Grating Length 130/150 mm

40 mm

Figure 4: A schematic layout of the side cooling mechanism for the gratings

7. Design Review The design will be reviewed and approved by RRCAT before commencing the fabrication process of the gratings. All necessary information about the beamline required for the design of the grating will be provided after the purchase order. However it is the responsibility of the supplier to ensure the performance of the grating.

8. Safe packing The gratings shall be in OEM packing. They shall be packed with sufficient care so that they do not undergo any damage during transit and withstand tropical weather during the transport. The grating shall be packed and sealed in dry nitrogen gas or in a similar inert atmosphere. The packing shall ensure that there is no deterioration in the performance of the gratings at RRCAT with respect to that in factory. Shock sensor shall be provided on the packing box.

9. Acceptance Criteria The suppliers shall provide the test report for the following measurements: Before the start of groove manufacturing: 1. Roughness and slope error measurement of the substrate shall be provided, 2. The design of the grating grooves and the calculated diffraction efficiency curves shall also be provided.

8

The report of the above test will need approval of RRCAT before the fabrication of the gratings. After the fabrication of the grooves and before shipment: 1 Measurement of groove density No shall be carried out. 2 Measurement of groove profile of the gratings as per the finalized design will also be carried out. All the values of these tests shall be as per the values mentioned in Table 1-5. The test reports should be supplied to RRCAT before the shipment of the gratings. Only after the acceptance of the test reports by RRCAT in writing, the gratings should be shipped.

Compliance chart The supplier must fill the following compliance chart and send it as a part of the quotation: S. No

1

2

Supplier’s compliance

Tender requirements The supplier should quote separately for various gratings Bidder qualification: i. The supplier shall be an original manufacturer (OEM) of the item, or an authorized supplier of the OEM, or standard synchrotron beamline component supplier. ii. The company shall have supplied at least six soft X-ray gratings in the past three years for Synchrotron beamlines. The list of beamlines where similar gratings have been supplied by the company shall be provided with the offer. iii. The supplier shall have the facility for the metrology of these gratings. The details of the instruments available with the supplier shall be mentioned in the offer.

Technical specification of the grating (G1A) Parameter Indent specification Grating G1A Shape Planar Grating type Laminar (VLS) Geometrical dimension 130 × 30 mm2 (± 0.1 mm in both dim.) Optical dimension 120× 20 mm2 (± 1 mm in both dim.) Thickness 40 ± 0.5 mm Substrate material Silicon RMS slope error of the Meridional: ≤ 0.15 arcsec starting substrate Sagittal: ≤ 1.75 arcsec RMS substrate roughness ≤ 0.3 nm Coating material Au or Pt Coating thickness 30 ± 10 nm Groove density at the center 770 lines/mm

9

Supplier’s value

Remark

of the grating (No) Groove axis

Grating parameter

Grating spacing parameters

± 2 lines/mm Perpendicular to the long axis (meridional axis) within ± 0.5o G/L = 0.6 ± 25% , GD = 19 ± 20 % nm a1= - 5.52×10-4 mm-1 (±1 %) a2= 2.28 × 10-7 mm-2 (± 20%)

Technical specification of the grating (G2A) Parameter Indent specification Supplier’s value Grating G2A Shape Planar Grating type Laminar (VLS) Geometrical dimension 130 × 30 mm2 (± 0.1 mm in both dim.) Optical dimension 120 × 20 mm2 (± 1 mm in both dim.) Thickness 40 ±0.5 mm Substrate material Silicon RMS slope error of the Meridional: ≤ 0.15 arcsec starting substrate Sagittal: ≤ 3 arcsec RMS substrate roughness ≤ 0.3 nm Coating material Au or Pt Coating thickness 30 ± 10 nm Groove density at the center 700 lines/mm of the grating (No) ± 2 lines/mm Groove axis Perpendicular to the long axis (meridional axis) within ± 0.5o Grating parameter G/L = 0.6 ± 25% , GD = 17 ± 20% nm a1= - 5.54×10-4 mm-1 (±1 %) Grating spacing parameters a2= 2.30 × 10-7 mm-2 (± 20%)

Remark

Technical specification of the grating (G3A) Parameter Grating Shape Grating type

Geometrical dimension Optical dimension Thickness Substrate material RMS slope error of the starting substrate

Indent specification Supplier’s value G3A Planar Laminar or blazed (VLS) If both available, they may be quoted separately 130 × 30 mm2 (± 0.1 mm in both dim.) 120 × 20 mm2 (± 1 mm in both dim.) 40 ± 0.5 mm Silicon Meridional: ≤ 0.15 arcsec Sagittal: ≤ 3 arcsec

10

Remark

≤ 0.3 nm Au or Pt 30 ± 10 nm 1400 lines/mm ± 2 lines/mm Perpendicular to the long axis (meridional axis) within ± 0.5o Grating parameter G/L = 0.6 ± 25 %, GD = 8 ± 25 % nm a1= - 5.54×10-4 mm-1 Grating spacing parameters (±1 %) a2= 2.30 × 10-7 mm-2 (± 20%) Technical specification of the grating (G1X) Parameter Indent specification Supplier’s value Grating G1X Shape Planar Grating type Laminar (VLS) Geometrical dimension 150 mm × 30 mm (± 0.1 mm in both dim.) Optical dimension 140 mm × 20 mm (± 1 mm in both dim.) Thickness 40 ± 0.5 mm Substrate material Silicon RMS slope error of the Meridional: ≤ 0.15 arcsec starting substrate Sagittal: ≤ 2.5 arcsec RMS substrate roughness ≤ 0.3 nm rms Coating material Au or Pt Coating thickness 30 ± 10 nm Groove density at the center 900 lines/mm of the grating (No) ± 2 lines/mm Groove axis Perpendicular to the long axis (meridional axis) within ± 0.5o Grating parameter G/L = 0.6± 25% ; GD = 11 ± 25% nm a1 = -5.55×10-4 mm-1 (± 2 %) Grating spacing parameters a2 = 2.31×10-7 mm-2 (± 20 %) Technical specification of the grating (G2X) Parameter Indent specification Supplier’s value RMS substrate roughness Coating material Coating thickness Groove density at the center of the grating (No) Groove axis

Grating Shape Grating type Geometrical dimension

G2X Planar Laminar or blazed (VLS) 150 mm × 30 mm (± 0.1 mm in both dim.) Optical dimension 140 mm × 20 mm (± 1 mm in both dim.) Thickness 40 ± 0.5 mm Substrate material Silicon RMS slope error of the Meridional: ≤ 0.15 arcsec starting substrate Sagittal: ≤ 2.5 arcsec

11

Remark

Remark

RMS substrate roughness Coating thickness Coating Material1 Groove density at the center of the grating (No) Groove axis

Grating parameters Groove spacing parameters

≤ 0.3 nm 30 ± 10 nm Au or Pt 1800 lines/mm ± 2 lines/mm Perpendicular to the long axis (meridional axis) within ±0.5o 2 G/L = 0.6± 33%; 3GD = 6 ± 30% nm a1 = -5.55×10-4 mm-1 (± 1 %) a2 = 2.31×10-7 mm-2 (± 20 %)

Common points related to all the gratings 1 Holding Mechanism: as per the details in figure 3. 2 Thermal Load and Cooling Mechanism: as per details given in section 6. The side face of the gratings ( length x height) where the cooling copper block is held, should be polished to < 1 micron meter rms roughness. 3 Design review: The design will be reviewed and approved by RRCAT before commencing the fabrication process of the gratings. However it is the responsibility of the supplier to ensure the performance of the grating. 4 Acceptance Criteria: The suppliers shall provide the test report for the following measurements: Before the start of groove manufacturing: 1. Roughness and slope error measurement of the substrate shall be provided 2. The design of the grating grooves and the calculated diffraction efficiency curves shall also be provided The report of the above test will need approval of RRCAT before the fabrication of the gratings. After the fabrication of the grooves and before shipment: 1. Measurement of groove density No shall be carried out. 2. Measurement of groove profile of the gratings as per the finalized design will also be carried out. All the values of these tests shall be as per the values mentioned in Table 1-5. The test reports should be supplied to RRCAT before the shipment of the gratings. Only after the acceptance of the test reports by RRCAT in writing, the gratings should be shipped.

12