NX-2000 operating instructions
Sample loading
1. Two plastic films are needed for the imprint. They are reusable and should be always
left on the wafer holder. The current plastic films can be used up to 250ºC. Different
plastic material must be chosen for higher-temperature applications.
2. Place the smaller-diameter film on the wafer holder. The film must cover the large
inner hole and extend to the outside edge of the first ring. It must be flat with no
wrinkles.
3. Place the mask and wafer in the center of the wafer holder. Make sure that the
thermocouple is touching the wafer. One can imprint samples of any shape and
size, even multiple samples, as long as one of them is placed on top of the
thermocouple.
4. Place the larger-diameter plastic film on the ring holder. The film is held in place by
eight tiny magnets placed over the cone-shaped protrusions. The film must be flat
with no wrinkles.
5. Place the ring holder onto the wafer holder. Align the cut-out notches of the ring
holder with the guide pins of the wafer chuck. The side of the ring holder with
magnets faces down.
6. Gently push the drawer into the chamber until you hear an audible click.
Imprint
1. Open the control program by double clicking on the NX2000 v. 3.5 icon.
2. Click on Users ⇨ Log in, enter ID and password. (Each user has a different log-in
set up by the clean room staff during the authorization.) Click OK to log in. If you
don’t want to log in, just click EXIT in the popped-up menu. The program will
terminate.
3. Click on Recipe to load the default recipe, or use User Set to compile a new one.
Default recipes are located in the General folder. If you select User Set, input the
following in the Process Parameters window:
1. NX-AP on/off (if NX-AP on/off is on, the Pre-temperature and Temperature
will be automatically set to 20°C).
2. Pumping Time (chamber) in the Pump box.
3. Pre-temperature and Pre-pressure in the Pre-Imprint box;
4. Temperature, Pressure, UV on/off, Processing Time, and UV on time (if UV
on/off is off, UV on time will be automatically set to 0) in the Imprint box. The
sample will be kept at the set temperature and pressure for the duration of
processing time. If desired, turn on the UV lamp or NX-AP.
5. Venting temperature in the Cooling and Vent box.
6. If both Pre-temperature and Temperature settings are below 25°C, the heaters
will not turn on during the imprint process. To save current recipe, press the Save
button and select a path. Each recipe has three indicators to show whether the
heater, UV lamp, or NX-AP process will be used.
7. Click on green Begin button. Click OK in the popped-up menu. The chamber closes
automatically and the vacuum pump evacuates the chamber. From this point on DO
NOT pull out the drawer until the program is finished and the cylinder stopped
moving. After the user-set pumping is completed, the imprint process begins
1
automatically. The temperature and pressure inside the chamber are monitored in
real-time and displayed on the monitor.
8. The chamber vents automatically after the imprint is finished. The status indicator at
the bottom of the screen displays To begin a new run. At this time, the operator can
open the wafer drawer and remove the sample.
9. To save current process data, click Profiles, select a file path, and click Save.
10. Repeat steps 3 through 5 for additional samples.
11. When done, click on Login ⇨ Exit to exit the program.
12. If you click the skip imprint button, the software will skip the imprint and proceed
with the cooling of the sample. At any time, the operator can abort the process by
clicking on the red ABORT button in the upper right corner of the screen. After
pressing Abort, the operator should wait for 1 minute and then follow the screen
instructions. An emergency stop may be executed by pressing the RED
Emergency button located under the monitor. After an emergency stop, the
operator must contact the administrator to reset the machine.
Alignment procedure using NX-AP and MA6 mask aligner:
1. You need to be familiar with the operation of MA6, including alignment and
exposure procedures.
2. Move theta of the stage back to its default position.
3. Select “Hard contact”, change “Al. gap” to 60 m and “Exp. Time” to 20 seconds.
4. Press “Change mask” and load the mask. Use the regular MA6 mask holder for 5
inch masks. Do not use the locking spring on the mask holder to clamp the mask.
Insert the mask holder into MA6 and press “Change mask” again.
5. Adjust the “WEC pressure” to 0.5.
6. Press “Load”. Pull out the substrate chuck and replace the MA6 chuck with the
Nanonex NX-AP and align the flat of the 4-inch wafer to the lines on the chuck.
7. Slide the substrate chuck back into the machine, then press “Load” and “Enter”. The
substrate chuck raises and the WEC is performed. Wait until the microscope lowers.
8. Align the wafer to the mask. If the distance between the wafer and the mask is too
large, gradually decrease the alignment gap until you get the best alignment.
However, the gap should never be smaller than 10 m. Because wafers are not
perfectly flat but have small curvatures, the wafer may start to touch the mask even
for gaps larger than 10 m. When you achieved the best alignment, press “Sep”
button to raise the substrate chuck and bring it “In contact” with the mask. Check the
alignment one last time.
9. Press “Exposure” button. Wait for a few seconds and unplug the vacuum to the mask
before the exposure is finished.
10. Unload the substrate. The mask should sit on top of the wafer and the mask and the
wafer should be attached in three points. Carefully remove the mask with the
attached substrate and use two 5-inch square PVC rubber sheets to seal it from both
sides.
11. Pull out the loading tray of the nanoimprinter and replace the standard wafer holder
with NX-AP holder. Be gentle with the thermocouple plug in the back of the holder.
Place the mask and the wafer enclosed in the PVC rubber on the NX-AP holder. The
mask must be on the top. Slide the loading tray in and imprint using the appropriate
program. Make sure that the NX-AP button is turned on in the recipe.
12. After the imprint, take your mask and sample out for the separation. Remove the
NX-AP chuck from MA6 and return the standard wafer holder into the nanoimprinter.
2