EBL Auto Alignment Protocol

EBL auto alignment protocol
Outline
- Mark Position Measurement
- Mark Detection
- Auto Alignment
Section I. Mark Position Measurement
- Place cassette upside-down, onto the circular Teflon platform located on the manual alignment fixture
- Remove the backing plate of the exposure aperture (A, B, C or D) by rotating the locking tab and aligning the keyway to facilitate the backing plate removal
- Place the sample into the exposure aperture with the PMMA coated side, facing DOWN
- Secure the backing plate onto the exposure aperture. Place the cassette on the microscope as shown in the image below
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- Turn the alignment stage power on
- Position the plate (face down), align the plate edge to build-in guiders and lock the plate
- Move the camera right underneath the aperture to be used
- Do theta adjustment. Focus on the sample, turn the backing plate of the aperture to adjust the theta
- Once theta adjustment is done, move the stage to align the longitude edge of the window with the microscope cross. Press the “//CE” button to activate the position meter. Move to the opposite longitude edge and record the position X
- Use the same technique to find Y. The center of the window should be at (X/2, Y/2)
- Move stage to (X/2, Y/2). Press “//CE” button again to zero the readings
- Move the microscope cross to the position of PQRS, record the coordinates, ignore the dot
- Blow off the entire cassette with dry Nitrogen Gas. A nitrogen gun is located in the rear of the laboratory
Section II. Mark Detection
- L-clk STGCOM
- L-clk EDIT PARAMETER
- L-clk SELECT (Opens Selection Menu)
- L-clk %2A, %2B, %2C, or %2D (highlight the sample location: Multi-piece cassette)
- L-clk APPLY
- L-clk CANCEL (Closes Selection Menu)
- L-clk MOVE (will move the stage to the CENTER of the APERTURE opening)
- Select RELATIVE POSITION* (For movement option)
- Enter the X (inverted) and Y coordinates of one alignment mark (The coordinated recorded in step #12 in Section I) Note: Only the X coordinate is inverted.
- L-clk MOVE (will move stage to the ALIGNMENT mark – P, Q, R or S)
- Select lens 4 on the console (This gives broader field of view).
- Press MAG button. Press DOWN ARROW to minimize magnification
- Press SEI button. Now the mark should appear on the screen. (Note: the line could be very thin with low current, e.g. I= 100pA. In this case, press UP ARROW to zoom in for better view)
- Move the stage to center the alignment mark to the center of display. Write down the coordinates of the mark (X4, Y4)
- Press CLR button to disable SEI. Switch to Lens 5
- Move the stage to (X5’,Y5’), where X5=X4+70 µm, Y5=Y4-50 µm. This set of coordinates gives the rough position of the mark under Lens 5.
- Press SEI. Center the mark to the center of the display. Write down the accurate coordinates under Lens 5 (X5, Y5)
- Deselect Rapid Scan. Set SPD to 55. Press SEI, ADD, MD, BLK buttons successively. Now mark detection signals should be displayed on the screen
- Press SEI, ADD, MD, BLK buttons successively. Now mark detection signals should be displayed on the screen
- Adjust the MAG to separate the peaks, and then GAIN button to increase the size of the peaks. In case of uneven peaks, use the X-ATTEN knob to even them out as best as possible
- Write down the GAIN and X-ATTEN values
Section III. Auto Alignment
- Calculate Theory Coordinates (XT, YT) of the mark. XT=XC+XD, YT=YC+YD, where is XC, YC are the coordinates of window center, XD, YD are the coordinates of the mark in CAD file.
- Calculate the Shift Amount: ΔX1=X5-XT, ΔY1=YT-Y5. (X5, Y5) are from step #17 in Section II.
- In SETWFR, select P mark detection and change both rough and fine scanning parameters. Input the GAIN and X-ATTEN values. Input calculated Shift Amount (ΔX1, ΔY1) into Material Offset.
- Click SAVE and RUN. Markers will be scanned and a shift amount will be displayed in the CALIBRATION window. This is the Modified Shift Amount (ΔX2, ΔY2).
- Change Material Offset to (ΔX2, ΔY2). Select PQRS marks and change rough/fine scan parameters for QRS marks. Click SAVE and RUN. Markers will be scanned and a shift amount will be displayed in the CALIBRATION window. This is the Final Shift Amount (ΔX3, ΔY3).
- Change the material offset to the final shift amount in SETWFR.
- In SDF file, change the window to the one with sample loaded. Change OFFSET to the final offset.
- In JDF file, change markers parameters are the same as designed. Make sure the dose is correct.
- Compile new MGN file.
- Do Array Check and expose the pattern.