User Manual for

1
User Manual for
Flat-Panel Detectors at
23A SWAXS Endstation
2
Table of Contents
1. System setting
page
1‐ 1
System configurations of Flat Panel sensor C10158DK-3957(X)
3
1‐ 2
Controls of the Detector
7
1‐ 3
Software HiPic
10
1‐ 4
Dark Current File Setting
17
2. Data reduction
2‐ 1
Data reduction (Background subtraction)
18
2‐ 2
Data collection and Transfer
19
2‐ 3
Data reduction with Fit2D (single mode)
21
2‐ 4
Data reduction with Fit2D Marco
26
3. Data Manipulation
3‐ 1
Beam center allocation
28
3‐ 2
WAXS q-calibration
33
3‐ 3
Combine 2D images (by Image J)
42
3‐ 4
Combine 2D images (by Fit2D)
44
3‐ 5
Combine 2D images (by Hi Pic 9.1)
3‐ 6
Standard samples: Ag-behenate and sPS
50
51
4. GIWAXS mode
4‐ 1
Instrument Calibration for GIWAXS setup
4‐ 2
The procedure of pole figure conversion from GIWAXS image
52
56
3
1-1. The System configurations of Flat Panel
sensor C10158DK-3957(X)
Flat-Panel
Detector
X-ray
Sample holder
Holder for
Detector
Scheme 1. The System configurations of Flat Panel detector for wide angle
x-ray scattering (WAXS) purpose at Beam line 23A, NSRRC
4
1-1-1. The Technical specification of Flat Panel sensor
C10158DK-3957(X)
5
1-1-2. Dimensional outline of C10158DK-3957(X)
Thickness of carbon fiber on top cover : 0.2 mm
Thickness of carbon fiber inside cover : 0.1 mm
1-1-3. Installing the Detector System and Overview
9V power supply
LVDS
Flat panel censor C10158DK-3957(X)
Windows
Computer
Software
Hipic
Ni PCI-1424
6
1-1-4. The real photon-sensitive area of C10158DK3957(X)
2.0mm
1.5mm
4.5mm
8.5mm
8.0mm
120.8 mm
7
1-2. Detector Controls
1-2-1. Activate the device and software.
(1) Turn on the power for power supply
(2) Double click the icon of Hi-Pic 9.1 on Desktop
,and Click OK to execute.
,
(3) The HiPic software control panel.
(4) Acquisition → Acquire, you can see the “acquisition control”.
Set “Exposure time”. (maximum 10 s for each frame), left click the “Acquire”
button then the acquisition getting start (Internal trigger mode).
1
2
3
4
8
1-2-2. Function Description
• Dark Current
Dark current (obtained without light) arises from thermal energy within the
Flat-Panel detector. If one wants to collect dark current data, please close the beam
and run the operation procedures as following pages.
Attention!!!
One should set the same exposure time for sample and dark current.
• Image acquisition
Acquire Mode
The measurement of very weak signals sometimes requires longer integration
times. Integration is generally performed in the background, so that the PC can be used
for other tasks while integration is going on. It works both in internal and external
trigger mode.
Analog Integration Mode (see page. 10)
The Analog Integration mode allows to accumulate images after image
acquisition.
• Trigger System (internal trigger and external trigger mode)
Trigger system is used to synchronize the BL23A detecting system. Hi-Pic 9.1
has two trigger modes (internal trigger and external trigger mode).
In internal trigger mode, Flat-Panel detector automatically and repeatedly
initiates acquisitions and outputs the signal. In external trigger mode, the detector
will not acquire a image until the trigger input signal (come from Pilatus) goes.
Attention!!!
If one want to collect SAXS and WAXS data simultaneously, please select “external” trigger source.
If one want to collect WAXS data independently, please select “internal” trigger source.
9
1-2-3. Trigger mode setting
•
Set the trigger mode of Flat-Panel
(1) Confirm the trigger mode: File → Options… → Camera
(2) Select Trigger Source mode. Set “internal” or “external” and click OK to execute.
3
4
10
1-3. How to operate Flat-Panel C10158DK
using Software HiPic.
•
Image acquisition in Acquire mode
1-3-1. Startup of Control Interface for Flat-Panel
(1) Click
or Acquisition→Acquire to open acquisition control .
(2) Set exposure time. (maximum 10 s for each frame; one can use Analog
Integration mode for longer exposure time for the setting)
(3) Right Click
or Acquisition→Sequence to open dialog and choose
“show sequence dialog”
1
2
3
Attention!!!
For weak intensity, please set the exposure time as 10 sec. if
strong scattering intensity, please set less exposure time, so
the maximum count is below the saturation limit of
130,000 ct .
11
Under Hi-Pic 9.1 / Sequence Control / Data Storage dialog,
(4) Set data storage mode: choose “HD <individual files – all modes>”
(RAM: store manually; HD: store automatically )
(5) Select the destination file path.
(6) Set filename and the file type. Data To TIFF Sequence(.tif) is recommended for
the convenience of data reduction processing by Fit2D. And Save the setting.
(the file will be saved automatically after measurement)
5
4
6
R46
Under Hi-Pic 9.1 / Sequence Control / Acquisition dialog,
(7) Set Acquisition mode as “Acquire” and set the frame number as “3” (No. of loops).
7
3
12
1-3-2. Start up of SPEC program for data collection.
A. In internal mode,
(8) When computer setting of Flat-Panel and Supersonic is ready,
• type “shutteron” to open the shutter for releasing X-rays to sample area . After
executing each running, please type “shutteroff ” to close the shutter, or type
“beamon $time
” to open the shutter for $time seconds then closed shutter
automatically. $time should be more than data collection time. This allows
some check and push-button processing time.
(9) Start running the measurement
Under Hi‐ Pin 9.1 / Sequence Control / Acquisition dialog,
Click “start” to start data collection.
3
9
If data collection is 5 sec/3 frames, one will get 3 files as:
filename001.tif
filename002.tif
filename003.tif
13
B. In external mode,
(10) Under Hi‐ Pin 9.1 / Sequence Control / Acquisition dialog, click
“start” to stand by the data collection.
(11) When computer setting of Flat-Panel, Supersonic, and Pilatus is ready,
type “psaxs $time” or “psaxsrock $time” in SPEC to start running.
11
If data collection is 5 sec/3 frames, one will get 3 files as:
filename001.tif
filename002.tif
filename003.tif
Attention!!!
Please always collect more than two image frames.
In the external trigger mode: the first image output by the 1st external trigger
CANNOT be used, due to the extra background accumulated during the
waiting time.
14
1-3-3. Image acquisition in Analog Integration mode
For WAXS data collection more than 10 s in one image, please execute below
steps:
(1) Under Sequence Control, set “Analog Integration” mode and number of loop
as “1”. (obtain one image after the measurement)
(2) Under Acquisition Control, set exposure time and number of images.
Click “Integrate” to start running.
(3)The file will be NOT saved automatically after measurement. Please right‐ Click
and choose “Save as” or FileSave as to save data.
If this dialog doesn’t appear, please click “” at the top right.
15
Recommend:
One should duplicate the data: (1) one set of raw data, and (2) the other set for
dark current‐ subtracted data, in case the background subtraction needs to be
modified later on.
Under Acquisition dialog, duplicate the data.
(1) File→save as to duplicate the data.
Ag‐ behenate
16
Attention!!!
One should set the same exposure time for sample and background in data acquisition.
The background‐ subtracted 1D profile should be obtained after data reduction
(Fit2D).
In Acquire mode,
total exposure time = number of loop * exposure time for each frame
(# of output image = number of loop )
In Analog Integration mode,
total exposure time = number of loop * number of exposures * exposure time for each frame
(# of output image = number of loop )
If user would like to obtain one image with long acquisition time in each sample, please set the
number of loop as “1”.
The maximum intensity (saturation counts) for each frame is 130,000.
Hint
One should set:
Dark current
1. the same exposure time for dark current
2. Only collect one image of dark current (# of image = 1)
As doing dark‐ subtracted, the dark current count will be subtracted in each frame.
Background (substrate)
1. The same acquisition time (number of exposure time for each frame) for sample
and background
 If measurements are interrupted owing to synchrotron X-ray beam lost. After X-ray
beam coming back (re-injection), please re-collect dark current and background
scattering again for consistent background subtraction (detailed below).
17
1-4. Setting for Dark Current File
(1) File→Options…→Correction →Background to open setup dialog.
(2) Get the dark current file .
(3) Click OK to save the setting.
Dark current image
1
1
2
3
18
2-1. Data reduction (Background subtraction)
1. Background subtraction
(1) Right‐ click and select “Do Background subtraction”.
(2) Select “(Y)” to obtain background subtracted data.
1
2
19
2-2. Data Collection and Transfer out to User’s
Folder)
User need put all related data into user folder for data reduction use.
Detector End (Old data will be removed regularly)
1.
2.
3.
Mount NAS on {Client} as Network Drive with user account
Download data files from {Detector End} to {Storage} through {Client}
by using FTP client
Do data reduction on {Client} or users’ laptops which can mount NAS as
Network Drive
20
 Data download procedures
(1) Connect to destination Detector End
(2) Establish connection in a new tab
(3) Download the data into user folder
21
2-3. Data reduction with Fit2D <single frame>
(1) Double click the icon of fit2D on Desktop
(2) Click “I ACCEPT “ to execute.
(3) Set the 1st and 2nd dimension of arrays as “1032” (pixel number of C9258DK, and
the pixel number of C10158DK is 2352) and click “OK” toward the main menu.
(4) Click “Powder Diffraction”
2
4
3
22
(5)
(6)
(7)
(8)
Click “Input” to input data.
Click “UP DIR” to search in file directory and select file.
Confirm the parameters and click “OK”.
Check the information and click “OK” to continue.
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6
7
8
23
(9) Click “cake”.
(10) Before integration, one should set the beam center. Please refer Section 3‐ 1. (All
calibration and reduction parameters will be ready before user operation. e.g. If
you have known beam center, please click “keyboard” to input the coordinate.)
(11) Set the circle sector area by 1→4. Click “Integrate “ to execute.
9
10
11
12
3

4
Counter‐ clockwise

1

2
24
(13) Correct the experimental geometry parameters and click “OK”.
(14) Correct the NUMBER OF AZIMUTHAL BINS to 1, and rectify the NUMBER
OF RADIAL/2-THETA BINS to 1032, and then click “OK”.
(15) Correct the Q-scan re-binning parameters and click “OK”.
13
15
14
25
(16)
(17)
(18)
(19)
Click “EXIT”.
Click “OUTPUT” to output data.
Click “CHIPLOT” to select the output type.
Correct the filename and click “
” to obtain the output file.
16
18
17
19
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2-4. Data reduction with Fit2D Marco
1. Create Macro File via “FP Data Reduction Protocol”
(1) Open the program “FP Data Reduction Protocol” and select the data
folder what the data in you want to reduce. And input the all parameters
you need to make data reduction
(2) Radial Bins: the pixel number of C9258DK is 1032, and the pixel
number of C10158DK is 2352
(3) Click the “Total Integrate” or not, you can choose total area
integration or arc area integration. If you use arc area integration, you
must input the other parameters on Start Azimuth, End Azimuth,
Inner Radius, and Outer Radius field.
(4) Run “FP Data Reduction Protocol” to generate the macro file
(TEXTIMAGE_INTE.MAC, and TEXTIMAGE_CAKE.MAC) on
your data folder.
1
2
3
4
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2. Run Fit2D program with marco files.
(5) In main menu of Fit2D, click ‘MACROS / LOG FILE’.
*Please go through once cake integration and return to main menu.
(6) In MACROS/LOG FILE MENU of Fit2D, click ‘RUN MACRO’.
(7) SELECT the macro file created by Fit2DMacro (TEXTIMAGE.mac,
IMAGEPLATE.mac,
or TIFF.mac)
5
6
28
3-1. Beam Center Allocation
(1) Double click the icon of fit2D on Desktop
(2) Click “I ACCEPT” to execute.
(3) Set the 1st and 2nd dimension of arrays as “1032” (pixel number of FP) and
click “OK” toward main menu.
(4) Click “Powder Diffraction”
(5) Click “Input” to input data.
2
3
4
5
29
(6)
(7)
(8)
(9)
Click “UP DIR” to search file in fie directory and select the standard sample data.
Confirm the parameters and click “OK”.
Check the information and click “OK” to read image.
Click “beam center” to enter the sub menu.
6
7
8
9
30
There are three methods to find the beam center:
1.
2.
3.
If the beam center is obtained, one can directly input the X and Y coordinates by
clicking “keyboard”.
If the beam center is unknown and a transmission pattern is collected, one can
determine the beam center by “2D Gaussian fit”.
If both beam center or transmission data are not given, one can determine the
beam center by putting standard sample (e.g. Ag-behenate) in beam and take
the scattering pattern. selecting 3 points with the left mouse button. The “circle
coordinates” method is: select several points define a circle and the beam
center will be assigned to the center of the circle.
1. determine the beam center by direct input
(10) Click “keyboard”.
(11) Input the known X-and Y-coordinate of beam center and click “OK”.
10
11
31
2. Determine the beam center by “2D Gaussian fit”
(10) Click “2D Gaussian fit”.
(11) Choose “two click mode” to determine beam center (the right corner appear
“ONE CLICK” indicate “Now is two click mode”)
• 1st click on the direct beam mark.
•
2nd click on the direct beam mark (left corner).
(12) After identification, beam center will be shown as “+”.
10
Two click mode
11
12
32
3. Determine the beam center by “circle coordinates”
(10) Click “circle coordinates”.
(11) Choose “two click” method to determine beam center.
(12) Select several points of the same scattering ring with the left mouse button. They
can define a circle, and the beam center will be assigned to the center of the circle.
•
1st click on the central image.
•
2nd click on the high‐ magnification image in left corner.
(13) Click “Click here to finish” to identify.
After identification, beam center will be shown as “+”.
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13
1st click
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4
3 2
1
12
6
11
10
7
8
9
2nd click
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3-2. WAXS q-calibration (instrumental parameters)
(1). rotation angles of the detector
(2). tilt angles of the detector
(3). sample-to-detector distance
3-2-1. Output the raw standard sample profile
(1) Double click the icon of fit2D
(2) Click “I ACCEPT” to execute.
(3) Set the 1st and 2nd dimension of arrays as “1032” (pixel number of FP) and
click “OK” toward main menu.
(4) Click “Powder Diffraction”
(5) Click “Input” to input calibration data.
2
3
4
5
34
(6)
(7)
(8)
(9)
Click “UP DIR” to search file in fie directory and select file.
Confirm the parameters and click “OK”.
Click “OK” to read the image.
Click “calibrant” as calibration mode.
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7
8
9
35
(10) Select “user defined” method (we used a calibration material not already in Fit2D
program).
(11) Put a list of d-spacings in a text file (Ag.txt). Search in fie directory and select the
calibration text file.
(12) Input speculated sample-to-detector distance, X-ray wavelength, pixel size, “NO”
in the X-ray wavelength refine, and “YES” in the beam center refine. After that,
click “OK”.
10
11
12
In Section 3-1, the beam
center is determined via
circle coordinate (defining
one circle. The position
may
be
offset
from
accurate beam position.
Therefore, user should
refine the beam center,
which can be calibrated by
multiple std peaks.
36
(13) Use the first peak in text file as datum point and utilize “two click” to select
several points in the scattering ring.
•
1st click on the central image.
•
2nd click on the high-magnification image (left corner).
(14) Click “Click here to finish” to identify. Fit2D will fit the rings corresponding to the
d-spacings (recorded in TXT file).
(15) Click “cake” to start integration.
13
1st click

2nd click
15
14
1
4
9
5
2
7
8
3
6
37
(16) Before running integration, one should set the beam center.
Please refer to section 3-1. if beam setting is ready, click “no change”.
(17) Set a circular sector with inner radius, outer radius, and azimuth angle delta by
1→4 points. Notice that the azimuth angle must be calculated with counterclockwise rotation.
(18) After Fit2D computing, one can obtain the correct sample-to-detector distance
and detector curvature. Click “OK” to next.
(19) Correct number of azimuthal bins as “1” and click “OK”.
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17
2
1
4
3
18
19
Attention!!!
Record the parameters
for data analysis.
33
38
(20→24) Save data:
Click “output →
chiplot →
filename→
choose destination folder and correct filename → OK”.
20
22
21
23
24
39
3-2-2. Establish a linear calibration of wavevector transfer q
1. Obtain the peak position.
Plot data by Origin and utilize Gaussian-fit to find the peak position.
40
2. Obtain polynomial correction formula
(1) Record all the peak positions in col (a), type the corresponding theoretical values
in column, and plot.
(2) Utilize “fit polynomial” to fit the data correlation.
(3) Set the polynomial order as “5”, choose “show formula on graph”, and click “OK”
to obtain polynomial correction formula.
1
2
3
41
3. Revise 1D WAXS profile of standard sample
(1) Input polynomial correction formula in a text file.
(2) set the approximation correction formula p(x) equal to that:
col(e) = p(x) = p(col(c))
to calibrate and obtain accuracy q value.
1
2
4. Compare the q‐ calibrated and standard profiles.
FP2D-Ag-std
14000
Ag std
20101225-8K
12000
Intensity(a.u.)
10000
8000
6000
4000
2000
0
0.2
0.4
0.6
Å
q(
-1
)
0.8
1.0
42
3-3. Combine 2D images (by Image J)
If user collects multi-frame data, one can combine a number of 2D images into
one for a better presentation.
1. Startup of Image J
(1) Double click the icon of ImageJ.
2. Import the multi‐ frames of data.
(2) File → Import → Image Sequence
(3) Open the image.
(4) Use File name contains to select the images and set the
parameters for frames-combination, and click “OK”.
2
3
4
43
(5) Click “↑”or “↓” to check each frame
5
3. Combine the multi-frames data.
(6) Image
→ Stacks → Z Projects…
(7) Set the parameters and choose the projection type as Average Intensity.
Click “OK” to output a “Intensity-averaged” file.
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7
44
3-4. Combine 2D images (by Fit2D)
• Startup of Fit2D image‐ combination
e.g. combine 3 images into one image
(1) Double click the icon of Fit2D
(2) Click “image processing (general)”.
(3) Click “input”.
(4) Click “UP DIR” to search in file directory and select file.
(5) Check the pixel input limit and click “OK” to read the 1st image.
2
3
4
5
45
(5) Click “exchange” to load another image.
(6) Click “input”.
(7) Click “UP DIR” to search in file directory and select the 2nd image.
(8) Check the pixel input limit and click “OK” to read the image.
5
6
7
8
46
(9-10) Click “maths → 
add ” to combine the two images and output it.
(11) Click “EXIT” to exit out the sub menu.
(12) Click “exchange” to show non‐ combined (1st) image. (Combination execution
will
overwrite the being viewed image.)
(13) Click “input” to load the 3rd image.
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11
10
12
13
47
(14) Click “UP DIR” to search in file directory and select the image.
(15) Check the pixel input limit and click “OK” to read the image.
(16-17) Click “maths →
add ” to combine the two images and output it.
14
15
16
17
48
(18) Click “EXIT” to exit out the sub menu.
(19) Click “output” to startup data output.
(20) Click “TIFF 8 bit” as file format.
(21) Click “Yes” to allow using the file
18
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20
21
49
(22) Input the lower limit of range as “0”. (Range: 0 ~ suggested value)
(23) Input the upper limit of range as “suggested value”.
22
•
•
23
The combined image would be saves in the same folder with fit2D.exe.
The filename of the combined image would be the same with the third loaded image.
50
3-5. Combine 2D images (by Hi Pic 9.1)
(1)
(2)
(3)
(4)
(5)
Double click the icon of Hi-Pic 9.1
Open image file: File --> Open
Processing  Arithmetic… to open dialogue.
Choose “F=F+D+C”.
Set the parameters, select another image file, and click “Proceed” to execute.
2
3
4
5
51
51
3-6. Standard samples: Ag-behenate and sPS
• Ag-Behenate
14000
12000
Intensity(a.u.)
10000
8000
6000
4000
2000
0
0.0
0.2
0.4
0.6
0.8
1.0
-1
q (Å )
• sPS
sPS_1D Gas (Co sen)
sPS_Mythen (Co sen)
sPS_2D FP
Intensity (a. u.)
600
2D FP image of
sPS
300
0
0.4
0.6
0.8
1.0
1.2
-1
q (Å )
1.4
1.6
52
4. GIWAXS mode
4-1. Instrument Calibration for GIWAXS setup
We have developed a standard procedure to correct the GIWAXS profile distortion
measured with the Flat Panel detector, due to the instrumental geometric parameters
(rotation and tilt angles of the detector and the sample-to-detector distance) together with
that given by beam reflection and sample size effect in GIWAXS; this includes the
calibrations of scattering wave vector q and q-resolution (δq) of the GIWAXS profiles.
4-1-1. Principle
Samples mixed from Ag-behenate powder and Si powder (AgSi) were prepared in
powder (bulk) and thin film forms. Since the peak positions and peak widths of the
standard sample AgSi are known, we can correct the wave vector q and q-resolution (δq)
via the following calibration steps. First, the AgSi bulk in transmission WAXS was first
conducted to calibrate the three instrumental parameters: rotation angle (θR) and tilt angle
(θT) of the detector and sample-to-detector (S-D) distance via fit2D software. These
parameters were then applied to the 1D GIWAXS profiles (out-of-plane and in-plane)
measured for an Ag-Behenate-Si thin film. The hence obtained GIWAX profiles display
obvious broadened and offset peaks from that given by WAXS, due presumably to the
beam reflection and sample size effects. A standard interpolation method (via a
polynomial fitting) was adopted to place these peaks back to the corrected q-positions
(with 0.5% accuracy), so that the both in-plane and out-of-plane GIWAXS can largely
overlap the WAXS profiles of the AgSi sample. The same q-correction obtained then can
apply to other GIWAXS profiles measured under the same instrument geometry for
unknown samples (same instrument setting and sample size).
Flat Panel Det.
∆θd
∆θb: view angle from sample point to beam source
∆θs: view angle from sample point to detector
∆θd: view angle from detector pixel to whole sample
∆Q=4πcosθ∆θ/λ
pixel
∆θs
∆Q/Q=cotθ∆θ
2
[∆θ] =∑θ
2
i
∆θb
sample
Scheme 1. Geometry distortion in GIWAXS measurement
beam source
53
AgSi_bulk out_of_plane
AgSi_film 0.15o out-of-plane
AgSi_film 0.15o in-plane
(b)
Intensity (a. u.)
(a)
2
4
6
8
10
12
14
16
18
20
22
24
-1
q (Å )
Figure (a). 2D-GISAXS pattern of AgSi thin film. In-plane and out-of-plane GISAXS profiles as the
function of qxy and qz were integrated from the left and right sectors, respectively.
Figure (b). 1D-GISAXS profiles of standard AgSi bulk and AgSi thin film (in-plane and out-of-plane).
4-1-2. Correct scattering wavevector q (step 1-3)
Step 1: Obtain instrument setting parameters
Conduct transmission WAXS with the standard AgSi powder sample, and obtain the three instrumental
parameters: (1). Sample-to-detector (SD) distance, and (2). rotation (θR) and (3) tilt (θT) angles of the FP
detector, with respect to the beam incidence, using fit2D software.
Step 2: Obtain GIWXAS profiles of AgSi film with SD, θR, and θT.
Conduct GIWAXS for an AgSi film, and obtain 1D in-plane and out-of-plane GIWXAS (as illustrated in
the Figure (b) below) via sector integration (Figure (a)), using fit2D with the three previous determined
parameters of SD, θR, and θT.
Step 3: Obtain q correction function by polynomial fit
Plot GISAXS peak positions vs. std peak positions, and obtained the polynomial fit for the q-correction
function. For better accuracy, third ordered of polynomial fit with s “3” with intercept set as “0” were
used, as shown blow. With the calibrated q-axis, GIWAXS profile of Ag-Si film now can overlap that
measured for the Ag-Si powder in transmission WAXS.
22
peak position of AgSi std (nm-1)
20
Model
Polynomial
Equation
y = Intercept + B1*x^1 + B2*x^2 + B3*
x^3
Weight
No Weighting
0.00152
Residual Sum of
Squares
18
1
Adj. R-Square
Value
16
Intercept
B
14
Standard Error
0
--
B1
1.02546
0.00473
B2
0.00212
9.07676E-4
B3
-6.58633E-5
3.50865E-5
(c)
12
10
8
6
4
2
qreal = 1.02546*qmea+0.00212* qmea -0.000065863* qmea
2
3
0
0
2
4
6
8
10
12
14
16
18
20
peak position of AgSi film (nm-1)
Figure (c). Polynomial correlation profile and function for wave vector q calibration.
54
2
δ (qsam) = 0.00162+ 0.04279*q – 0.00333 *q – 0.0025 *q
Intensity (a. u.)
106
standard AgSi bulk
AgSi film (out-of-plane)
δqmeasured
polynomial fitting
(e)
0.06
Intensity (a.u.)
105
0.04
104
0.02
103
102
2
4
6
8
10
12
14
16
18
20
22
24
26
28
0.00
0.0
30
δq /peak width, FWHM (Å-1)
0.08
AgSi Bulk out_of_plane
AgSi film 0.15o out_of_plane (correction)
AgSi film 0.15o in_plane (correction)
(d)
3
0.5
1.0
1.5
2.0
q (Å-1)
q (nm-1)
Figure (d). 1D WAXS profile of standard AgSi bulk and 1D GIWAXS profiles of AgSi film.
Figure (e). 1D WAXS profile of AgSi powder and 1D GIWAXS profiles (out-of-plane and in-plane) of
Ag-Behenate-Si thin film. A third degree polynomial is used to correct the peak q-resolution.
Step 4: Obtain the q-resolution function of GIWAXS
(1) Measure the peak widths of the standard sample thin film of Ag-behenate with FP detector.
(2) Obtain Instrument resolution δqinstr2 = δqGIWAXS2 – δqstd2 (qstd is the peak width of the sample
measured in a high resolution WAXS mode for intrinsic sample peak widths)
(3) Build a δqinstr-resolution function from all the δqinstr values, using a polynomial fit.
(4) Unknown sample peak width δqsam2 (at q) = δqGIWAXS2 – δqinstr2
Ag_film (correction)
Intensity (a. u.)
(f)
2
3
4
5
6
7
8
-1
q (nm )
Figure (f). 1D GIWAXS profiles of AgSi film and the Gaussian fitting peak.
55
4-1-3. Correction Table of q-resolution for GIWAXS
The instrument q-resolution (peak broadening due to wavelength resolution, detector
pixel resolution, beam divergence, and sample size), δqinstr, on the GIWAXS peak is
estimated from error propagation: δqinstr = (δq2GISAXS − δq2std samp)1/2. Interpolating all the
obtained δqinstr values for the samples peaks (via a polynomial fitting), we can obtain the
instrument q-resolution as a function of q, at the specific instrument setting. With the
instrument q-resolution function, the unknown sample peak widths then can be deduced
using δqSam = (δq2GISAXS − δq2instr)1/2.
sample
Ag-behenate
powder
Si powder
Std. Peak
Corrected
Correction
Peak Std peak
width
GIWAXS peak Accuracy
#
(Å-1)
(FWHM)
(Å-1)
(%)
δqstd
Measured peak
GIWAXS (FWHM)
δqGIWAXS
(sam.+instru.)
Extracted
instrument qresolution
(FWHM)
δqinstr
Re-calculated
instrument qresolution
(FWHM)
δqinstr*
Accuracy of fitted
instru. q-resolution
(%)
δqinstr − δqinstr *
δqinstr *
1
0.1076
0.00789
2
0.2152
0.2152
0.00
0.00487
0.0118
0.01075
0.01065
0.92
3
0.3228
0.3221
0.22
0.00519
0.0161
0.01524
0.015
1.57
4
0.4304
0.4319
0.35
0.00554
0.0197
0.0189
0.01922
1.67
5
0.538
0.5387
0.13
0.00599
0.0239
0.02314
0.02329
0.64
6
0.6456
0.6456
0.00
0.00652
0.0272
0.02641
0.02718
2.93
7
0.7532
0.7554
0.29
0.00694
0.0327
0.03196
0.03089
3.34
8
0.8608
0.8623
0.17
0.00739
0.0352
0.03442
0.03439
0.09
9
0.9684
0.9692
0.08
10
1.076
1.079
0.28
11
1.1836
1.1858
0.19
13
1.3988
1.3877
0.79
0.03356
0.0585
0.04792
0.04809
0.36
15
1.614
1.643
1.80
0.01782
0.0669
0.06448
17
1.8292
1.824
0.28
0.02782
1
1.9994
0.05558
0.05384
0.0538
0.07
0.0138
Table 1. Peak positions and deviation (%) of after GIWAXS q-calibration for an AgSi thin film. (out-ofplane). Peak width of true standard AgSi bulk, measured AgSi thin film, and convoluted instrumental
smearing. [photon E: 15 keV / SD distance: 142.35 mm / peak width by Gaussain fit]
56
4-2. The procedure of pole figure conversion from
GIWAXS image
1. Load image
File → load image (ex: xxx.tif)
2. Rotation the image
Processing → image correction → rotation → manully entering a value (deg): → Process
Step 1
57
Step 2
Step 3
The image after Rotation
58
3. Define the beam center
Processing → find center → manual set (New beam center can be find form
from fit2D software)
4. Establish pole figure
Analysis → WAXD → fiber-liker:Fraser correction
Step 1
59
Step 2
Wavelength : 0.082657 nm
Sample tile angle : 0.2 degree
Detector pixel size : 0.05 mm (for FP detector)
Sample-to-Detector distance : 130 mm
5. Output file
File → Save → Floating point tiff file (image format)
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