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If you by accident unload a cassette without evacuating the exchange-chamber, you must tick 'EXCH EVAC' and load your cassette onto stage and unload it to the autoloader again.
If you by accident unload a cassette without evacuating the exchange-chamber, you must tick 'EXCH EVAC' and load your cassette onto stage and unload it to the autoloader again.
= Calibration of condition file =
From the EBX menu on workspace 1, open the calibration window ‘Clb’. From this window, a previously used condition file (calibration file) dedicated to a certain aperture setting and current setting is loaded, re-calibrated, and saved again.
1 Load and restore a condition file, click ‘Select condition file...’, choose the file from the list, e.g. ‘0.2nA_ap7’ and click OK. Restore the file by clicking ‘RESTOR/Edit Parameter...’. From the RESTOR window, click ‘Excecute’; the machine will now restore the conditions of the colum, this will take a few minutes. Exit the RESTOR window by clicking ‘Cancel’.
 
2 Execute ‘CURRNT’ click ‘CURRNT/Execute’. The program ends by stating the average value of five measurements of the e-beam current; write this average current in the logbook.
3 Execute  INITAE; click 'INITAE/Execute'.
4 Execute INITBE; click 'INITBE/Execute'.
5 Execute the pre-defined set of sub-programs called ‘daily’: click 'Commands/Batch...'. Click ‘Condition file...’, choose ‘daily’, and click OK and execute. This set of programs takes around 8-10 minutes to run.
6 Edit and execute ‘DRIFT’: click ‘DRIFT/Edit Parameter...'. Select ‘Acquisition of bottom BE mark’, and click ‘Save’ and ‘Execute’. Exit the window by clicking ‘Cancel’. If you are calibrating the high current of a double-current exposure you should increase the scan width to 40 microns and note the position of the drift mark. When calibrating the low current of a double-current exposure, make sure DRIFT scans the same drift mark as the high-current condition file.
7 Edit and execute the ‘HEIMAP’ sub-program parameters:
With the path DRF5M, which is recommended for first print exposures (mask writing mode), HEIMAP is executed right before the machine exposes, and the machine will use the HEIMAP settings saved at this point. The e-beam software can only save and use one setting, even if you expose two wafers/chips. Therefore, perform and save HEIMAP with the settings you wish to perform right before exposure.
When the exposure is performed in direct writing mode, i.e. the pattern is aligned to P and Q marks on the wafer or virtual chip mark detection is obtained, the result of HEIMAP is discarded and can be omitted in initial calibration. In this case, HEIMAP can be executed to check the substrate has been mounted correctly in the cassette.
HEIMAP measures the height of the substrate with a laser beam, the beam spot size onto the substrate is 0.94 mm x 0.08 mm. It is important to measure height at substrate positions where the beam is not deflected from holes or mesas.
1. Click 'HEIMAP/Edit Parameters...'. Enter
    Material type: Wafer (unless you expose a mask)
    Material size: The size of loaded wafer in units of inches, i.e. 2, 4 or 6. If you use the chip cassette or the 65mm stamp cassette, choose 3".
    Multi-piece window: the location of the wafer/chip. You should perform HEIMAP on all loaded wafers/chips.
    Zigzag: use X->Y
    Number of height measurement points X, Y: standard is 5 in both X- and Y-direction.
    Height data measurement pitch: define the pitch of the measurements points to fit the size of the exposed pattern.
    Insert an offset to the measurements if your pattern is located away from (0,0).
    DO NOT change any other parameters in HEIMAP
2. Save the settings by clicking 'Save', and execute the program.
3. When the program has been executed, the result of the test will appear in the result-display area of the calibration window. The measured height in the 25 points should not deviate more than +/- 50 mu.
(8 Execute SETWFR and CHIPAL - If you are aligning in semi-automatical mode, see section 7)
9 Save the condition file by clicking 'Save/Edit Parameter...'. Click 'Acquisition of latest status' to the right and (after the parameters appear in the window) click 'Apply/Save'. Note in the status line that the condition file has been saved.
= Exposure of mgn-files =
1 Open the exposure program, ‘Exp’, from the EBX Menu.
2 Find and load your magazine file: click ‘File/Magazine File’ and choose the magazine file from the location ‘/home/eb0/jeoleb/job/danchip’.
3 Check that the name of the desired magazine-file appears in the Magazine filename field, then click ‘Execute’.
4 Click ‘YES’ if you agree on the information in the ‘Pattern Writing Execution Check’-window.
Before the exposure starts, some inital calibration will be performed such as CURRNT and HEIMAP. When measuring HEIMAP, the last saved condition of HEIMAP will be used.
After finished exposure, the machine will display whether the exposure succeeded.
= Alignment of wafers or chips =
Alignment of wafer or chip requires specific training.
First time you align on a set of wafer marks, you need to optimise the gain settings of the scan. This is done by the subprogram ACGRG.
When the gain settings are known, you can execute SETWFR and CHIPAL.
== AGCRG ==
Open and edit AGCRG, in the program window
    Enter the measured (from pre-aligner output) P mark position
    Click 'RG mark detect condition: Setting' and adjust scan width and position. Use a large scan width (200-600 microns). In 'Scan type' choose 'fine scan', 'box scan' and choose the correct mark (cross or L-shaped). Start with an 'X only' scan.
    Save and execute AGCRG
        If the program finds the mark, ask the program to transfer the gain settings to SETWFR P (both rough and fine) or SETWFR Q. Scan again with same settings but choose 'Y only' in the 'RG mark detect conditions'.
        If the program does not find the mark, try a larger scan width and execute AGCRG again, and/or try to scan 'Y only' instead.
AGCRG
Open and edit AGCRG, in the program window
    Enter the measured (from pre-aligner output) P mark position
    Click 'RG mark detect condition: Setting' and adjust scan width and position. Use a large scan width (200-600 microns). In 'Scan type' choose 'fine scan', 'box scan' and choose the correct mark (cross or L-shaped). Start with an 'X only' scan.
    Save and execute AGCRG
        If the program finds the mark, ask the program to transfer the gain settings to SETWFR P (both rough and fine) or SETWFR Q. Scan again with same settings but choose 'Y only' in the 'RG mark detect conditions'.
        If the program does not find the mark, try a larger scan width and execute AGCRG again, and/or try to scan 'Y only' instead.
If the program does not find the mark you can find it manually using the SEM. Remember to minimise the use of SEM:
    Open the Stage program from EBX menu
    In 'sspvideo' click beam/beam-off
    Move stage to mark position (setting/movement)
    In 'sspvideo' click 'change/BE SEM'
    open 'adjust' and 'Setting' and start the SEM.
    Find the mark ROUGHLY and turn off the SEM again.
Enter approximate mark position into AGCRG and execute AGCRG again.
== SETWFR ==
1. Before saving your condition file you should run the sub program 'SETWFR'.
SETWFR will scan your P and Q marks and align the exposure to the position of these.
From the calibration window, click 'SETWFR/Edit parameters'. Fill out the SETWFR parameters.
    Choose measurement mode 'Semi Auto'
    enter the material size and slot number (e.g 4A)
    enter the material center offset (from the pre-alignment) and L-edit coordinates of P mark and Q mark.
    In P-mark rough/fine scan settings, adjust scan settings and enter the width of your marks. Also check the gain settings are ok.
    Repeat point 4 for Q-mark rough/fine
    Click save and execute the program.
SETWFR
1. Before saving your condition file you should run the sub program 'SETWFR'.
SETWFR will scan your P and Q marks and align the exposure to the position of these.
From the calibration window, click 'SETWFR/Edit parameters'. Fill out the SETWFR parameters.
    Choose measurement mode 'Semi Auto'
    enter the material size and slot number (e.g 4A)
    enter the material center offset (from the pre-alignment) and L-edit coordinates of P mark and Q mark.
    In P-mark rough/fine scan settings, adjust scan settings and enter the width of your marks. Also check the gain settings are ok.
    Repeat point 4 for Q-mark rough/fine
    Click save and execute the program.
Standard gain setting for gold wafer marks or etched marks (5-10 µm deep):
BE Coarse gain
1
BE Middle gain
14
WAVE offset
128
BE Fine gain
128
BE offset
2020
If the program cannot find the marks, you can either adjust the scan conditions, or gain settings. Also, test SETWFR again with 'OFFSET (P-mark)' from the pre-aligner output.
Find the mark manually and let SETWFR scan the mark to align the sample:
As a last alternative, you can chose to find the mark manually; this is however not recommended.
    SETWFR will ask you whether you wish to find the mark manually, click OK.
    In 'sspvideo' click 'change/SEM'
    open 'adjust' and 'Setting' and start the SEM.
    Center the mark ROUGHLY and turn off the SEM again as fast as possible.
    Click to continue the SETWFR scan at your present position
    It might be necessary to repeat the procedure with the Q-mark.
Please note that you should NOT align with the SEM but only roughly center the mark so you are sure the mark will be scanned with your scan settings.
When the subprogram 'SETWFR' has found the P and Q marks
    When SETWFR executes successfully feedback the 'P mark offset' to the OFFSET in the sdf file and re-compile the mgn-file.
If SETWFR cannot find your marks:
    Unload the cassette, unmount your chip/wafer and remove the resist from your chip/wafer marks. Mount, pre-align and load your sample again and execute the exposure using manual alignment (see procedure in troubleshooting, section 8).
== CHIPAL ==
Before saving your condition file you should run the sub program 'CHIPAL'.
CHIPAL will scan 1 or 4 of your chip marks and align the exposure to the position of these. Also, if HSWITCH is set to measure height in chip mark positions, the beam will be focused to the (average) height of the substrate near chip marks.
During calibration, CHIPAL can be tested on one chip by the subprogram CHIPAL:
From the calibration window, click 'CHIPAL/Edit parameters'. Fill out the CHIPAL parameters:
    Choose 'mode 1' if you have 1 chip mark per chip or 'mode 4' if you have 4 chip marks per chip
    If 'AGRCG' is executed, the machine will optimise the gain settings before mark detection; this is not recommended. Use instead same gain settings as in SETWFR. If the gain settings need to be adjusted for chip mark detection, use the subprogram 'AGRCG' on your chip mark (see section 7.1)
    Leave 'Height measurement execution', 'HEIGHT' and 'SUBHEI' unmarked.
    Enter the center position of one of your chips in 'Chip center coordinate position'; this position is in wafer coordinate systems.
    Enter chip mark positions of M1-M4 in chip coordinate system, i.e. if you have a chip mark 1 mm x 1 mm from the center of the chip, M1 coordinates are (X,Y)=(1000,1000).
    Save and execute the program.
If the program can not detect your chip marks, change the scan conditions ('RG mark detection condition') and try again.
= Troubleshooting =
    No EBX Menu is open in any of the desktops: Open a console (click on arrow above the text ‘CPU’ on bottom menu bar) and from location (DTU)/ type ‘ebxmenu’.
    The ACHK or WRTEST programs are nowhere visible: Open Analysis form EBX Menu; from here you can find ACHK and WRTEST.
    I forgot to tick the EXCH EVAC before transferring my cassette from the e-beam writer to the autoloader: Transfer your cassette back into the e-beam ('Carry in'), then tick 'EXCH EVAC' on, and click 'Carry out' to transfer the cassette to the autoloader and pump down the exchange chamber
Basic unix operations
cd job
Change directory to 'job'
cd ..
Go one directory up (parent directory)
dir List the directories and folders
CTRL+p (CTRL+n) Scroll to previous (next) command
Click on middle mouse button
Copy highlighted text, or paste copied text
Tripple-click on left mouse button
Highlights all text in a window (works in some windows only)
== Calibration problems ==
    No current can be detected when executing CURRNT: Call one of the contact persons to get help.
    The DISTBE subprogram runs for more than 15 minutes: Stop the subprogram from the calibration window (Command/Subprogram Stop). Click 'DISTBE/Edit Parameter'. Click 'Settings'. Change the scan position by 0.2 microns, both in X and Y. Save and execute DISTBE again. If DISTBE runs successfully, acknowledge the write to memory request, and run the last subprogram of the 'daily' batch manually. If it does not help, call one of the contact persons for help.
    The detection of AE/BE or wafer marks gives an either too saturated or too noisy signal: Edit the AGCAE/AGCBE or AGCRG programs by entering the position of your AE/BE or wafer mark and execute the program. When the program finish successfully, apply the settings to other relevant subprograms; see 'the INITAE or INITBE mark cannot be detected' section.
    The INITAE or INITBE mark cannot be detected: The system has probably drifted too far away from the mark to be able to detect the mark. Increase the scan width by doing this:
        Highlight INITAE and click 'Edit parameter'
        From the INITAE window, click 'AE mark detection condition Setting'
        Increase the scan width to around 40 µm, click apply, and execute INITAE again
        If the mark has been detected, click Update in the INITAE-window when the subprogram has finished
        Decrease the scan width to its original value, click apply and execute INITAE again
    The same procedure applies to INITBE; here, the scan width can be increased to more than 40 µm, though. If the marks still cannot be detected, call one of the contact persons to get help.
    When the AE and BE marks has been found, the settings should be applied to all other relevant subprograms:
        Click 'Setting..' in the INITAE window
        Click 'Applies to another subprogram' in the 'detection condition' window
        Click 'All Select' in the 'applies to another subprogram' window; this highlights all subprograms on the list. Click 'Subprograms that can be set' to execute.
    The same procedure applies to the BE mark detection. Test whether subprograms can be executed by running e.g. SFOCUS and PDEFBE (quite short programs).
 
== Alignment problems ==
    SETWFR cannot detect my P and Q marks: Unload your wafer/chip, remove the resist from your wafer marks and repeat your exposure with manual alignment:
    Alignment commands for manual alignment (see 'sdf- and jdf-file preparation' manual):
    Change the global mark detection in the sdf-file: GLMDET M (i.e. manual detection). Recompile the magazine file.
    Calibrate as without alignment.
    Execute exposure, wait until the machine prompts for action:
        The machine will start a subprogram 'SETWFR' right before the exposure and move the stage to the position of the P-mark as stated in the jdf-file. Click 'YES' to manually align the machine to the global marks. In order to move the stage to the correct position of the P-mark (as detected with the optical pre-alignment), open the 'Stg' program from the EBX Menu.
           
        Move the target position (stage position) by clicking 'Setting...' and edit the X and Y parameters to the values found from the pre-alignment. Click 'Movement' to execute the movement.
        From the sspvideo (can be opened by 'Image' from the EBX Menu), start the SEM from 'Change/SEM'. Adjust the Brightness/Contrast and scan width by opening the Image Setting and Image Adjustment windows ('Setting...' and 'Adjustment...' buttons).
        Find the P-mark by adjusting the stage position using the step movement from the stage controller. When the mark is centered, click 'Pattern writing continuation' and repeat the procedure for the Q-mark. Finish the global alignment by clicking 'Pattern writing continuation', and the exposure will start.
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