Karl Suss MJB3 Contact Mask Aligner Standard Operating Procedure
Transcription
Karl Suss MJB3 Contact Mask Aligner Standard Operating Procedure
Karl Suss MJB3 Contact Mask Aligner Standard Operating Procedure This machine is to be used by authorized personnel only. To obtain training on this instrument, please contact the Lab Manager directly (rm 1017 X4-9831/4-0260) If at any time during use unknown problems occur, stop all work immediately. Leave notice that the machine is not to be used and contact the Lab Manager (X49831/4-0260) 1. Select the proper mask and clean it with acetone and then with IPA (isopropyl alcohol). Dry the mask with nitrogen blasts. 2. On the black security box, flip the switch to ON; a BLUE LED will illuminate on the front of the box. Swipe your Columbia ID to activate the aligner, which will automatically alert the security computer that the aligner is in use. An internal timer will start, which runs for one hour. Five minutes before time is up the LED will turn on to alert the user. Swipe your ID card again to reset the internal timer if more time is needed. 3. Flip the gray switch labeled Nitrogen on the pressure supply box UP to supply N 2 pressurized gas to the system. The aligner will not work properly without activating gas flow. 4. Check the UV lamp power supply, located on the sub shelf of the vibration isolation table. It should read 195 watts (this will increase with lamp age). Choose either Cl1 for positive resist or Cl2 for negative resist. 2 a. Cl1 is calibrated to provide 6mW/cm of illumination at 365nm 2 b. Cl2 is calibrated to provide 10mW/cm of illumination at 405nm 5. Loosen the two mask holder knobs on the front of the sample platform. Remove the mask aligner holder carefully and place it onto the vibration table with the vacuum ring side up. There will be a 2 inch glass plate covering/protecting the vacuum ring. Flip the gray switch labeled MASK down to release the vacuum holding the glass plate. Remove the glass plate and center the appropriate mask on the vacuum ring, the metallized side of the mask should be up. Flip the mask switch up to activate the vacuum holding for the mask plate. Replace the mask holder in the aligner with the mask facing down; tighten the holder knobs finger tight. Do not flip the MASK switch off unless the mask holder has been removed and placed on the vibration table with the mask facing up. Failure to follow this direction could result in a shattered mask. 6. Check to be sure that the substrate platform height (CONTACT) lever is rotated to the front of the machine and that the platform is lowered all the way (the platform height micrometer on the front of the machine should be turned fully clockwise). The SEPARATION lever is towards the back of the machine (no separation). Slide the substrate platform out to the right of the machine exposing the sample holder assembly. Place the sample in the center of the assembly covering the vacuum holes. If the substrate is skewed on the holder use the rotation knob on the front of the aligner to straighten it. 7. Slide the platform back into position. Looking through the binocular stereo microscope, using the lowest magnification, locate and focus on the center of the pattern to be exposed. The microscope motion handle has two buttons, which release brakes on its motion in either X or Y. Either one of the brakes, or both, may be released at once. 8. Visually, with and without the microscope, align your substrate with the pattern on the mask by using a combination of the X and Y micrometers and the rotation knob. 9. When the substrate is aligned to your satisfaction, raise it to meet the mask surface by slowly rotating the CONTACT LEVER to the back of the aligner. You may gauge the separation by looking between the substrate and the mask from the left side of the aligner. A reflection of the substrate off the mask will be visible: proper adjustment is reached when the substrate and its reflection meet (you can also see a series of fringes on the mask plate as contact occurs). At this point the substrate is in contact with the mask. The CONTACT LEVER should be all the way back at this point, clicking into place and igniting the CONTACT light on the aligner control panel. i. If the substrate meets the mask before the Contact light turns on, use the platform height micrometer knob at the bottom of the front of the aligner to lower the platform a small amount (clockwise motion). ii. If the Contact light turns on before the substrate meets the mask, use the platform height micrometer to raise the platform until the substrate and mask connect (counter clockwise motion). 10. If alignment between the mask and the substrate is satisfactory and correct, skip to Step 12. 11. If the alignment between the mask and substrate is off, pull the SEPARATION Lever all the way forward. This should extinguish the CONTACT light and lower the platform height enough to perform fine alignment with the X, Y and rotation micrometers. When the alignment is correct, push the SEPARATION Lever back. The CONTACT Light should turn on again. 12. SET the TIMER for the desired exposure time. Typical exposure times for AZ5214E resist are between 6 and 12 seconds. Primary variables are the resist thickness and the desired level of over/under exposure (if any). Experimentation will determine the best levels for your project. Set the TIMER by rotating the outer knob to select the time coefficient (between 0 and 3.5) and setting the multiplier with the inner knob. e.g. For instance, choosing 2 on the outer knob and x10s on the inner knob will result in a 20s exposure. 13. When ready, PRESS the GREEN EXPOSURE button. The microscope head will automatically raise up and the light housing will slide forward over the mask. The UV Lamp shutter will then open. Safety glasses with UV protection are to be warn the entire time you are using this equipment. DO NOT STARE AT THIS LIGHT, it is strong in the UV range and may damage the retina and hinder vision. Warn anyone present in the Yellow Room when you are using this system. 1. When the exposure is finished the housing will automatically slide back and the microscope will return to the normal position. 2. Rotate the CONTACT Lever to point forward; this will lower the substrate platform. Slide the platform out to the right and remove your sample. 3. Use the X, Y and rotation knobs to realign/re-center the platform to the aligner housing if necessary. 4. If you have more samples to expose using this mask, repeat the procedure beginning with step 5 above. 5. When finished with all exposures on this mask, loosen the mask holder knobs and remove the mask holder to the table top, placing the assembly with the mask facing up. FLIP the MASK switch OFF (turning off the vacuum) and remove the mask. Place the glass cover plate over the vacuum port. Turn the vacuum ON by flipping MASK switch ON. Replace the mask holder and loosely tighten the knobs. 6. If you have more samples to expose using a different mask, repeat the procedure from step 4. 7. If finished with all exposures, first flip the NITROGEN switch on the pressure supply box to OFF (the two gauges will drop to zero). 8. On the black security box, flip the switch to OFF. 9. Be sure to log in the date, time and your initials with an abbreviated list of the processes you performed. Also note comments and/or any problems experienced with system and enter these into the Aligner Log Book.