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KarlSuss MA-6 Aligner, karlsuss & karlsuss2

The Karl Suss MA-6 Contact Aligner system can perform precision mask-to-wafer front- or back-side alignment and near-UV photoresist exposure in hard- and soft- contact, as well as high and low vacuum contact; proximity is not available. Our current configuration accommodates 3", 4" and 6" wafers and pieces. SNF has two MA-6 aligners (karlsuss and karlsuss2).

Picture and Location

 KarlSuss1

This tool, karlsuss, is located at D1 on the Lab Map.

 

KarlSuss2

This tool, karlsuss2, is located at CD1 on the Lab Map.

Background

The Karlsuss MA-6/BA-6 contact aligner is a 1:1 contact alignment/exposure tool. Because the alignment is done manually on a wafer-to-wafer basis, the Karlsuss aligner is less suitable for high through-put IC production and more designed for applications in R&D projects and small scale production. Since it is a 1:1 exposure system, the resolution of the exposed patterns on the wafer is basically determined by the resolution of the mask used. Although the light available for exposure is the DUV (240nm) and the I-line (365nm) as in the ASML, the system is limited to a minimum of  1um (vacuum contact) in resolution compared to 0.45um or less on the ASML. This higher resolution on ASML is achieved through diffraction-limited precision reduction optics whereas in the Karlsuss resolution is maintained by exposing the wafer in contact with the mask. Sub-micron masks are expensive to make and it is recommended to use a reduction lithography system such as the ASML for those projects. In terms of alignment, it is limited to about +-0.5um (+-1.0um in practice) in alignment accuracy for the front-side and +-1.0um (larger in practice) for the back-side. If the resolution capability of the Karlsuss meets your requirements, it is a better tool to use when you have large fields and/or require many design variations on your mask.

 

 

 

Process Capabilities

Cleanliness Standard

The karlsuss appears in all three equipment groups (clean, semiclean, and gold) as part of the litho & analytical tools set.

 

Performance of the Tool

What the Tool CAN do

  • Contact 1:1 aligner
    • DUV and IR capability (karlsuss)
    • 4", 5", and 7" size mask holders available
    • Wafer sizes of 6", 4", 3", 2" and pieces down to few mm*
    • Maximum wafer thickness: 4.3mm
    • Split field microscope for top-side and bottom-side viewing
    • Split-field objective separation distances from 50mm to 100mm
    • Best resolution = 1 um or better in vacuum contact mode (1.0um hard contact, 2.5um soft contact)
    • Alignment accuracy of +-0.5um (+-1.0um practical) for front-side and +-1.0um (>>+-1.0um practical) for back-side
    • Allows alignment gaps of 1um-1000um
    • Ability to expose for long periods

     

What the Tool CANNOT do

  • proximity exposure is not available
  • Cannot align to pieces with less than 38mm spaced alignment marks
  • Although the tool can achieve sub-micron resolution in vacuum contact, sub-micron masks are expensive. It is recommended to use a reduction lithography tool like the ASML for sub-micron features and alignment requirements
  • Achieve best resolution without EBR
  • Achieve best alignment accuracy when using the tool to expose on the top surface of a thick layer (bonded SOI layer) of ~10's to 100's of microns and trying to align to alignment marks on the lower layer.

 

Process Monitoring

 

How to Become a User

 

  1. "All Litho" is required before training on any of the lithography tools. Contact the trainers for the class schedule and training materials (which must be reviewed before the class).
  2. Read all material on the SNF website concerning this tool, including Background, Process Capabilities, Operating Procedures and Process Monitoring.
  3. Print the SNF Shadowing Form on clean room paper and contact a qualified user of the wet bench to arrange to ‘shadow’ them while they use the tool. You are responsible to be with that labmember for the full time they are operating the tool, and it would be intelligent to ask questions and try to become as familiar as possible with the wet bench during this ‘shadowing.’  You may have to shadow the qualified user more than one time. The qualified user and you will have to sign the SNF Shadowing Form.
  4. Contact SNF training contact on the Equipment Summary page.

Operating Procedures: Frontside Align

  • Contact Aligner with 4 contact modes: soft contact, hard contact, low vacuum and vacuum
  • Mask Size: 4 inch , 5 inch and 7 inch, 5 inch mask holder is the default
  • Lamp settings are:
    KarlSuss1 (left one): CH2 = 365 nm, 15 mw/cm2
    by request only: CH1 = DUV, 240 nm
    KarlSuss2 (right one): CI1 = 365nm, 15 mw/cm2 or CI2 = 405nm, 30mw/cm2
  • Wafer size: pieces, 3 , 4 and 6 inch
  • Maximum wafer thickness: 4.3 mm
  • Largest exposure area: 4 and 6 inch diameter
  • Objective Separation: 38 to 100 mm
  • Alignment Marks: Mask Designer discretion (should be able to locate by eye)

Special Notes or Restrictions:

  • There is a two-hour limit on reservation length on this tool during prime time
  • Do not lean on machine while doing alignments

NOTE: BOLD ALL CAPS DESCRIBES A BUTTON ON THE MACHINE.

Startup

  1. Enable "karlsuss" or "karlsuss2"
  2. Front Panel
    POWER is left on - do not turn it off (top left side). If power is off, contact Maintenance!
  3. TV monitor
    Switch power ON.
  4. Constant Intensity Controller
    Verify desired lamp is selected:
    KarlSuss2 (right one): CH1 (365nm, 15 mw/cm2) or CH2 (405nm, 30mw/cm2)

    KarlSuss1 (left one): CH2 (365 nm, 15 mw/cm2)
    by request only: CH1 (DUV, 240 nm)
  5. Alignment Stage, center wafer stage
    Set X and Y stage micrometers to 10 (on red scale).
    Set wafer rotation to center point, rotation indicator should be centered.
  6. Keyboard:
    Make sure Multiple Exposure or BSA Microscope are not selected.
    Only when dealing with thicker resist you need to turn on the Multiple Exposure.
    No key light should be on or flashing!

 

Select and edit program

Keyboard

  • To select a program, press SELECT PROGRAM key until the desired program is selected
    Soft-Cont/Cont
    Hard-Cont/Cont
    LVac-Cont/Cont
    Vac--Cont/Cont
    (Proximity is not available)

  • To choose parameters, press EDIT PARAMETERS key, the keypad will flash (select MULTI EXPOS if needed).
    Press right or left arrow keys to scroll through the parameters.
    Press up or down arrow keys to change parameter settings, press and hold the Fast key to change faster.
    Soft and Hard contact:
    • Exposure time [seconds], check the log sheet for exposure time.
    • Alignment gap [um], 40 µm or higher is recommended.
    • WEC type (do not change)

    LowVacuum and Vacuum contact:
    • Exposure time [seconds]
    • Pre Vac [s] (do not change)
    • Full Vac [s] (do not change)
    • Vac Purge [s] (do not change)
    • Alignment gap [um]
    • WEC type (do not change)
    Press EDIT PARAMETERS again to execute the save, the flashing should stop. Verify program on display.

 

FOCUS and ALIGN WAFER (front side) for the first layer only

  1. Load the mask
  2. Load the wafer
  3. Expose

 

FOCUS and ALIGN WAFER (front side) for the second and subsequent layers

  1. Load the mask
  2. Locate alignment marks on mask
  3. Load the wafer
  4. FOCUS and ALIGN WAFER (front side)
  5. Expose

 

 

Load the mask

Verify that the microscope is in up position!

  • If not, press F1 and Enter and wait for microscope to lift up.

Press CHANGE MASK key.  This key and the Enter key will flash.  Do not hit Enter yet.

  • Carefully pull mask holder out, flip it over, and place it on the plastic tray at the left of the tool.
    Caution! Plastic tray could break if bumped into.
    5-inch mask holder is the default for both tools. There is one 4-inch mask holder in the drawers between the two tools.
    • If you would like to use the 4-inch mask holder, disconnect the vacuum hose at the tool (not the tray). Push in on the green knurled knob and gently pull on the hose. Store the 5-inch mask holder in the shelf between the two tools. Connect the vacuum hose to the 4-inch mask holder.  
  • Place the mask, chrome side up, onto the mask holder against the three pins. 
  • Press the flashing ENTER key to turn the vacuum on and verify that vacuum is holding mask.
  • Turn the mask holder over and carefully slide the mask holder back into the tool.
  • Press the flashing CHANGE MASK key to lock the mask holder into place.
  • Press F1 and Enter keys to lower microscope.

 

Locate alignment marks on mask


Objective Color Code:
5x: red
10x: yellow
20x: green

 

Keyboard

  • Press TOP/BOTTOM key, light should be on when focusing the mask (light off: focus on wafer).

Front Panel

  • TOP SUBSTRATE knobs, left or right objective, are for fine focusing.
  • SPLITFIELD knob: Center position for both objectives or single field, right or left objective.
  • Switch ILLUMINATION knob to TSA  (topside alignment).
  • Adjust the Illumination with TSA knob.

Microscope

  • Keep the right and left apertures at the TSA-microscope in center position.
  • Coarse focus is possible by using the large focus knob, placed on top of the microscope, rotate very carefully.

  • How to focus the objectives on the mask:

    1. Start with the lower magnification objective: 5x: red

    2. The TOP SUBSTRATE knobs are for fine tune focus. They have a range of three full turns. Move both knobs 1.5 turns (halfway) from either extreme.

    3. Use the large coarse focus knob on top of the microscope to put the alignment marks in focus as best you can.

    4. Adjust the fine tune knobs to get a precise focus.

    5. If you need to, increase the magnification to 10x: yellow, refocus using steps 2-4. 
     
    6. For very small features, increase the magnification again to 20x: green, refocus using steps 2-4.

     

Find targets on mask:

  • Use x and y arrow keys (fast is optional) and theta knob (right to large focus knob).
  • Adjust the spacing of the objectives to see both alignment targets. The adjustment knobs are located to the right and left of the objectives.

 

Load Wafer

Keyboard

  1. Press the LOAD key. When the LOAD light is on, the Enter and Unload lights should flash.
  2. Pull the load slide straight out.
  3. Select chuck (caution, they cost 15K each!):
    • One quartz chuck for pieces, with red vacuum seal
    • One solid chuck for 3 inch wafers, with red vacuum seal
    • One quartz chuck for 4 inch wafers for soft or hard contact only
    • Two quartz chucks with red vacuum seal for 4 inch wafers
    • One solid chuck for 6inch wafers per request.
  4. Align the white line (on the chuck) up with the pin (on the load slide).
  5. Verify that the chuck and the red vacuum seal are clean from stains or particles.
    • To remove particles use the N2 gun.
    • Use IPA on a clean wipe to remove any stains from the chuck, careful, no IPA should get on the red vacuum seal!
  6. Place wafer (wafer flat facing front) on the center of the chuck, be careful not to scratch the chuck or the red vacuum seal! Ensure that all vacuum grooves on the chuck are covered.
  7. Press the Enter key (Enter key flashes), ensure the vacuum holds the wafer in place.
  8. Slide the load slide all the way back into the machine.
  9. Press the Enter key again. The WEC (Wedge Error Compensation) will be performed. The wafer is adjusted parallel to the mask. After the WEC, wafer and mask are not in contact and can be aligned.

 

 

FOCUS and ALIGN WAFER (front side)

Keyboard

  • Press TOP/BOTTOM key, light should be off for adjusting wafer focus.

 

Front Panel

Use BOTTOM SUBSTRATE knobs to focus wafer ( for right and left side)

 

Alignment Stage

Use micrometer screws to align wafer in X, Y and theta  (only if you are exposing more than on layer).



 

FOCUS and ALIGN PIECES (front side)

Keyboard

  • Press TOP/BOTTOM key, light should be off for adjusting wafer focus.

 

Front Panel

Use BOTTOM SUBSTRATE knobs to focus wafer ( for right and left side)

 

Alignment Stage

Use micrometer screws to align wafer in X, Y and theta  (only if you are exposing more than on layer).

 

 For wafer pieces....to adjust rotation from side to side of the piece.
  • Move to first location to be viewed and push SET REF button
  • Move to second location to be viewed and push SCAN
  • Push SCAN to jump between the two location (making adjustments in X, Y and theta between scans).
  • We strongly suggest the use of the chuck for pieces. If you have to use the chuck for 4 inch wafers, contact staff.

 

 Check Alignment

  • Push ALIGN CONT EXPOS button to go in and out of contact (light OFF indicates contact mode, light ON is in separation). Make adjustments in separation mode and move to contact mode to check alignment.
    • ALIGNMENT CHECK key
      With this key you can check the alignment prior exposure. Particles between mask and wafer or the edge bead can affect the alignment of the wafer to the mask. To test that the alignment remains stable while moving to exposure position, all parameters of the exposure program are triggered except the exposure itself. This key is active for the exposure programs: Vacuum Contact, Low Vacuum contact, and Hard Contact.
      If not satisfied with the alignment, press the ALIGNMENT CHECK key again to release the wafer back into alignment gap. ALIGN CONT EXPOS light should go on automatically indicating wafer is in separation mode.
      Re-align using micrometer screws and repeat the above procedure.
      • If using GRAB IMAGE, push GRAB IMAGE to unselect it (light goes off) before pushing ALIGNMENT CHECK.

  

Expose Wafer

  • Press EXPOSURE (first check that MULTI EXPOS key has been pressed if multiple exposures are being done).
    The Exposure key brings the wafer into contact, performs the complete exposure program and exposes. There is no chance to realign if a misalignment occurred during the exposure program.  Be sure you have finished your alignment of mask and wafer before pressing this key.
    The objective head will lift and the exposure assembly will slide out over the mask.
    Don't look into the UV light during the exposure.
    After the exposure, the exposure assembly moves back, and the objective head will drop back down over the mask.
  • Pull the load slide out all the way (vacuum turns off automatically) and remove the exposed wafer from the chuck, don't scratch the chuck or the red vacuum seal.
  • Press ENTER to confirm.
    If you have more wafers, repeat the procedure.
    You should develop and inspect the first wafer before you expose the second wafer, you might have to adjust the exposure time!
    When all wafers are finished, slide the load slide all the way back into the machine. and follow the Shutdown procedures.

     

SHUTDOWN

  • Press CHANGE MASK
    Wait for objective head to lift.
    Press F1 and enter if optics are not in up position.
  • Place mask holder on the plastic tray. Caution!!! Plastic tray could break if bumped into.
  • Press ENTER to turn off mask vacuum and remove the mask
  • Slide the mask holder back into the machine.
  • Press CHANGE MASK to lock mask holder in place
  • Push ENTER to confirm -- no vacuum at mask, display should now read: Ready for LOAD.
  • Switch off all keys on keyboard, no key light should be on or flashing.
  • 5x objectives are default.
  • 4 inch wafer holder and 5 inch mask holder are default.
  • Turn OFF power to TV
  • Important: Leave the main power ON
  • Disable karlsuss or karlsuss2
  • Fill out log-sheet: resist type, resist thickness, exposure time
  • Clean mask:
    Rinse the mask using acetone/methanol/IPA at the litho solvent bench.
    Mask cleaner using water under pressure is available.

 

Helpful Hints 

 

 Button Information

OPTION, PERFORM CLAMPING AND PREBOND buttons are not options

  • ALIGN CONT EXPOS wafer goes in and out of contact (light on = in separation mode)
  • F1 access to RAISE/LOWER OPTICS option
  • CHANGE MASK locks or unlocks mask holder in position
  • LAMP TEST maintenance only
  • SELECT PROGRAM choose exposure mode
  • EDIT PARAMETERS edit parameters of chosen mode
  • SCAN scans from point to point across wafer pieces (where split field is not possible)
  • SET REFERENCES selects first point for SCAN mode (see instructions)
  • ENTER usually used to confirm steps were done (see instructions)
  • MULTI EXPOSE selects expose wait cycles for long exposures
  • ALIGNMENT CHECK wafer goes into selected mode of contact for checking prior to exposure. May push EXPOSE to remain in contact and expose wafer.
  • EXPOSURE begins exposure
  • FAST change speed of movements with arrow keys (light on = fast)
  • LOAD load wafer
  • UNLOAD unload wafer
  • LEFT select left optic for movement (x axis for topside optics, x and y axis for backside optics)
  • RIGHT select right optic for movement (x axis for topside optics, x and y axis for backside optics)
  • BOTH select both optics for movement (x axis for topside optics, x and y axis for backside optics)
  • BSA MICROSCOPE selects backside align optics
  • TOP/BOTTOM switches between focus of mask (top) and focus of wafer (bottom)
  • GRAB IMAGE grabs focused image of mask (for doing all backside alignments OR for doing frontside alignments with large separations or high power
  • Toggles
    • BSA MAG toggle between low and high power. Use low power to find location on wafer then toggle to high power to align it.
    • BSA/TSA toggle between backside align and topside align optics

 

 

Operating Procedures: Backside Align


  • Contact Aligner with 4 contact modes (vacuum, vacuum hard, hard contact and soft contact)
  • Mask Size: 4 inch (consult staff) and 5 inch (6 inch wafer upgrade available), 7 inch (consult staff)
  • Wafer size: pieces, 3 to 6 inch
  • Maximum wafer thickness 4.3 mm
  • Largest exposure area: 4 inch diameter (6 inch wafer upgrade available with some limitation for BSA)
  • Objective Separation: 38 to 100 mm
  • Alignment Marks: Mask Designer discretion (should be able to locate by eye)

Special Notes or Restrictions:

  • There is a two-hour limit on reservation length on this tool during prime time
  • Do not lean on machine while doing alignments
  • Most materials are allowed on this machine. See MATERIALS section for details.

 

NOTE: BOLD ALL CAPS DESCRIBES A BUTTON ON THE MACHINE.

Startup

  1. Enable "karlsuss" or "karlsuss2"
  2. Front Panel
    POWER is left on - do not turn it off (top left side). If power is off, contact Maintenance!
  3. TV monitor
    Switch power ON.
  4. Constant Intensity Controller
    Verify desired lamp is selected:
    KarlSuss2 (right one): CH1 (365nm, 15 mw/cm2) or CH2 (405nm, 30mw/cm2)

    KarlSuss1 (left one): CH2 (365 nm, 15 mw/cm2)
    by request only: CH1 (DUV, 240 nm)
  5. Alignment Stage, center wafer stage
    Set X and Y stage micrometers to 10 (on red scale).  This is CRITICAL!
    Set wafer rotation to center point, rotation indicator should be centered.
  6. Keyboard:
    Make sure Multiple Exposure is not selected.


Select and edit program

Keyboard

  • To select a program, press SELECT PROGRAM key until the desired program is selected
    Soft-Cont/Cont
    Hard-Cont/Cont
    LVac-Cont/Cont
    Vac--Cont/Cont
    (Proximity is not available)

  • To edit a program, press EDIT PARAMETERS key, the keypad will flash (select MULTI EXPOS if needed).
    Press right or left arrow keys to scroll through the parameters.
    Soft and Hard contact:
    • Exposure time [seconds]
    • Alignment gap [um]
    • WEC type (do not change)

    LowVacuum and Vacuum contact:
    • Exposure time [seconds]
    • Pre Vac [s] (do not change)
    • Full Vac [s] (do not change)
    • Vac Purge [s] (do not change)
    • Alignment gap [um]
    • WEC type (do not change)

    Press up or down arrow keys to change parameter settings, press and hold the Fast key to change faster.
    Check the log sheet for exposure times.
    Alignment gap: 40 µm or higher is recommended.
  • Press EDIT PARAMETERS again to execute the save, the flashing should stop. Verify program on display.

LOAD MASK

(Don't forget to tell the mask maker that this is a BSA mask.  It is incredibly important as it tells them to invert the pattern 180 degrees)

Verify that the microscope is in up position! If not, press F1 and Enter and wait for microscope to lift up.

 

Press CHANGE MASK key.  This key and the Enter key will flash.  Do not hit Enter yet.

  • Carefully pull mask holder out, flip it over, and place it on the plastic tray at the left of the tool.
    Caution! Plastic tray could break if bumped into.
    5-inch mask holder is the default for both tools. There is one 4-inch mask holder in the drawers between the two tools.
    • If you would like to use the 4-inch mask holder, disconnect the vacuum hose at the tool (not the tray). Push in on the green knurled knob and gently pull on the hose. Store the 5-inch mask holder in the shelf between the two tools. Connect the vacuum hose to the 4-inch mask holder.  
  • Place the mask, chrome side up, onto the mask holder against the three pins. 
  • Press the flashing ENTER key to turn the vacuum on and verify that vacuum is holding mask.
  • Turn the mask holder over and carefully slide the mask holder back into the tool.
  • Press the flashing CHANGE MASK key to lock the mask holder into place.
  • Press F1 and Enter keys to lower microscope.

 

LOCATE ALIGNMENT MARKS

  • Push BSA
  • Toggle to splitfield or single field on the upper control panel
  • Toggle the TSA/BSA to BSA/IR optics. This is for illumination of the backside of the wafer.
  • Adjust the illumination with the panel knobs labeled BSA/IR.
  • Use x and y arrows to find targets on mask
    • The two objectives can be moved simultaneously or independently from each other by selecting BOTH, RIGHT or LEFT on the lower control panel.
    • 10x is the only magnification available for BSA
  • Focus the mask
    • Adjust the focus with the two potentiometers on the upper control panel labeled TOP SUBSTRATE.
    • TOP/BOTTOM button light should be ON when focusing the mask (light on is for mask level and light off is for wafer level focus). Push if necessary
    • When targets are located and in focus ...GRAB IMAGE .
      • Push GRAB IMAGE to store a picture of the mask image, the wafer will be aligned to that image.
        • Objectives can not be moved if the image is grabbed

Load Wafer

Keyboard

  1. Press the LOAD key. When the LOAD light is on, the Enter and Unload lights should flash.
  2. Pull the load slide straight out.
  3. Select chuck (caution, they cost 15K each!):
    • One quartz chuck for pieces, with red vacuum seal
    • One quartz chuck for 4 inch wafers for soft or hard contact only
    • Two quartz chucks with red vacuum seal for 4 inch wafer
  4. Align the white line (on the chuck) up with the pin (on the load slide).
  5. Verify that the chuck and the red vacuum seal are clean from stains or particles.
    • To remove particles use the N2 gun.
    • Use IPA on a clean wipe to remove any stains from the chuck, careful, no IPA should get on the red vacuum seal!
  6. Place wafer (resist side up; align marks on the bottom, where you will be looking!) on the center of the chuck, be careful not to scratch the chuck or the red vacuum seal! Ensure that all vacuum grooves on the chuck are covered.
  7. Press the Enter key (Enter key flashes), ensure the vacuum holds the wafer in place.
  8. Slide the load slide all the way back into the machine.
  9. Press the Enter key again. The WEC (Wedge Error Compensation) will be performed.
    Wafer and mask are not in contact and can be aligned.

 

FOCUS and ALIGN WAFER

  • OPTIONAL!! If you are using HIGH MAGNIFICATION, you could start out with LOW POWER to locate the area of the wafer with your targets then toggle to HIGH MAGNIFICATION to do the alignment.
  • Use BOTTOM SUBSTRATE knobs to focus wafer ( for right and left side). TOP/BOTTOM button light is OFF.
  • Use micrometer screws to align wafer in X, Y and theta.
  • Push ALIGN CONT EXPOS button to go in and out of contact (light OFF indicates contact mode, light ON is in separation)
    • Make adjustments in separation mode and move to contact mode to check alignment

 

Expose Wafer

  • Press EXPOSURE (first check that MULTI EXPOS key has been pressed if multiple exposures are being done).
    The Exposure key brings the wafer into contact, performs the complete exposure program and exposes. There is no chance to realign if a misalignment occurred during the exposure program.  Be sure you have finished your alignment of mask and wafer before pressing this key.
    The objective head will lift and the exposure assembly will slide out over the mask.
    Don't look into the UV light during the exposure.
    After the exposure, the exposure assembly moves back, and the objective head will drop back down over the mask.
  • Pull the load slide out all the way (vacuum turns off automatically) and remove the exposed wafer from the chuck, don't scratch the chuck or the red vacuum seal.
  • Press ENTER to confirm.
    If you have more wafers, repeat the procedure.
    You should develop and inspect the first wafer before you expose the second wafer, you might have to adjust the exposure time!
    When all wafers are finished, slide the load slide all the way back into the machine. and follow the Shutdown procedures.

 

SHUTDOWN

  • Press CHANGE MASK
    Wait for objective head to lift. Press F1 and enter if optics are not in up position.
  • Place mask holder on the plastic tray. Caution!!! Plastic tray could break if bumped into.
  • Press ENTER to turn off mask vacuum and remove the mask
  • Slide the mask holder back into the machine.
  • Press CHANGE MASK to lock mask holder in place
  • Push ENTER to confirm -- no vacuum at mask, display should now read: Ready for LOAD.
  • Switch off all keys on keyboard, no key light should be on or flashing.
  • 5x objectives are default.
  • 4 inch wafer holder and 5 inch mask holder are default.
  • Turn OFF power to TV
  • Important: Leave the main power ON
  • Disable karlsuss or karlsuss2
  • Fill out log-sheet: resist type, resist thickness, exposure time
  • Clean mask:
    Rinse the mask using acetone/methanol/IPA at the litho solvent bench.
    Mask cleaner using water pressure is available.

 


 

Process Monitoring Results

The results of periodic exposure tests can be found in the Litho Qualification spreadsheets found here:

https://snf.stanford.edu/SNF/processes/process-modules/photolithography/photolithography-qualifications-1

 

 

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