...
Model Removal & Resin Stripping
Advanced Processing Procedures
Manual Interface Finding
WARNING: MANUAL INTERFACE FINDING MAY RESULT IN A COLLISION BETWEEN THE SUBSTRATE AND LENS IF DONE IMPROPERLY. IF YOU HAVE CONCERNS, PLEASE CONTACT A STAFF MEMBER BEFORE ATTEMPTING.
...
- Load your substrate in a sample holder. If the substrate is thicker or thinner than the holder depth (i.e. 700 microns thick for the Multi-DiLL holder), it is important to measure how much taller or shorter your substrate is.
- Add resin to your substrate and the objective.
- Load your sample as you would normally, select the correct holder and click OK.
- Do not click Approach Sample at any point.
- In the advanced camera settings, ensure that the light source is correct for your substrate - for opaque substrates use a Reflective Illumination, but for transparent substrates you will be better served with Transmission Illumination with all objectives.
- Approach the sample with the manual Z control. You may use coarse control initially until you reach a Z-height on the order of 9000um. For thicker substrates, it is recommended to stop earlier, substract your substrate height above the holder from 9000.
- During this step you should see the lens contact the resin, it will be very obvious, looking like a bubble moving across the microscope. Keeping Auto Contrast and Auto Exposure.
- Using the fine control, move the microscope slowly; you should slowly begin to resolve the substrate.
- For a 700um thick substrate this is typically a Z-value greater than 9800um.
- Turning off auto-contrast and auto exposure can be helpful; ensuring short exposure times but also smaller Gain (<15) will result in a clearer image.
- Once the substrate appears in view, turn off the microscope in Nanowrite and open AxioVision.
- While AxioVision loads, in the Nanowrite Advanced Settings console type ManualControl and click Submit.
- On the left hand side of the Manual Control interface is a section with Shutter Control. Set the laser power to a low value, typically 5%
- With AxioVision loaded, open the shutter. If you see a small white dot, this is the laser. If you cannot see it, you are either too close to the substrate and its focal length is past the surface of your substrate. Alternately, you may be too far from the substrate, however this is typically not the case if you have your substrate in focus.
- Using the fine Z control, slowly adjust the Z location towards your substrate until the white dot just disappears. Note this Z location - switching the microscope control unit to XYZ mode is helpful for this process as the Manual Control interface is not ideal for this step.
- Close the Shutter in Manual Control.
- Close AxioVision and Manual Control. Enable the Nanowrite microscope.
- Note: closing AxioVision and renabling the microscope will automatically turn on Auto-Contrast, you may wish to disable this again.
- Your substrate should eventually come into sharp focus, move the substrate on X and Y until you have identified where you would like to print.
- Modify your _data.gwl file:
- It will contain the line FindInterfaceAt $interfacePos, comment this out by adding "%" before the line
- If this line is not removed or commented out, the microscope will lose the position and attempt to automatically find the interface
- Load your print job and begin printing
- It may be valuable to have a small object (e.g. a cube) to test the print before starting a longer one. This can help validate your starting point and ensure that your print isn't floating or the laser is focused past your substrate.
- When your print is complete, click Exchange Sample Holder. This will back the objective from your print as normal.
See this short video below which follows the same process:
...
*Note - the Z values in this video are not necessarily reflective of other prints and should not be used as a reference.
Printing on Porous Substrates
For substrates with holes or other features, it is necessary to manually align the microscope. First, users should follow the Manual Interface Finding procedure. This can be done on any location on your substrate, however an area away from your desired print area is suggested. Once an interface has been determined, manual alignment can begin.
In the following steps, we are assuming that we are looking to find the center of a 1000um hole in the center of a substrate.
- Move around the microscope until the feature is visible. Ensuring the features are near center of the substrate as possible will prevent bubbles from forming and being moved around the lens.
- Make sure Center Cursor is on, there should be a dashed blue line on the microscope display. If it is not there, click Center Cursor.
- Move to one edge of the feature, roughly center, in this case the lowest point of the hole, keeping this in the center of the crosshairs.
- Move up 1000um on Y by inputting 1000um in the step size box and clicking the up arrow for stage adjustment. Note that in this case picking the Y axis is arbitrary and the X may be used just as easily as a starting point.
- Realign to the top of the hole, generally 10um increments are sufficient. Record the total distance added or subtracted from the initial 1000um.
- Move to the new Y center point by inputting half the net distance travelled in Step Size then click the down arrow once e.g. ((1000um-distance correction)/2).
- Move right on the X axis by current value in Step Size.
- Align the edge of the hole as with the Y axis. If the center appears to be misaligned with the Y axis, adjustments can be made now to align on this axis.
- Continue to move side to side and up and down in order to verify that the sample is centered.
- Record the X and Y coordinates of this center point.
- For multi-part prints, it is necessary to comment out any instance of FindInterfaceAt or CenterStage in the _job.gwl and _data.gwl files
- In lieu of CenterStage, a new center point can be added manually via the GoToX and GoToY commands, typically in the _job.gwl file.
- Formatting is GoToX number where number is the X coordinate of your new center point.
- In lieu of CenterStage, a new center point can be added manually via the GoToX and GoToY commands, typically in the _job.gwl file.
The short video below demonstrates the process for a 25x25 mm substrate with a 1mm center hole. The CAD models for this substrate are available for download in STL and STP format, as well as a drawing of the substrate.
~Video Forthcoming~
Applications
- Microfluidics
- Micromechanics
- Biomedical Engineering
- Micro-electro-mechanical systems
- Mechanical metamaterials
- Micro-optics
- Photonic metamaterials and Plasmonics
...