Evaporation Stack for OFETs, High Density
The evaporation stack holds the source-drain shadow masks and substrates in close contact for thermal evaporation. This is crucial for device fabrication because the source-drain channel is the most critical feature on an OFET. For use with the high-density OFET source-drain evaporation masks (sold separately).
The key component is the lower support, which is milled from a solid block of aluminium to provide high-precision recesses for individual shadow masks and substrates, and allows mixing-and-matching of shadow masks within a single evaporation.
|Size||75 mm x 75 mm|
|Thickness||2 mm (exc. bolts)|
|Material||Lower support: milled aluminium
Lid: stainless steel
Magnetic sheet: vinyl-laminated polymer resin with ferrite powder
|Substrate capacity||Radial design: 10 substrates
Square design: 12 substrates
Architecture of an Evaporation Stack
The diagram below shows an deconstructed view of how the evaporation stack fits together. At the base of the system is the lower support, which prevents the thin and flexible shadow masks from warping. This support has recesses in which individual masks are placed with the substrates placed on top of them. The lid is used to bolt everything together into a mechanically stable system that can be mounted in a deposition system at any orientation. Finally, a thick, low strength magnetic sheet is placed on to pull the shadow mask in close contact with the substrates (note that this differs from the low density evaporation stack where the magnetic sheet is placed underneath the lid).
Holds the shadow masks flush against the substrates
Holds the substrates in position
Up to twelve substrates per mask
Mix and match masks with different geometries within the same evaporation
Combined Lower Support (square) and Substrate Holder
Milled from a single piece of aluminium to provide mechanical support for the shadow masks and substrates.
PLEASE NOTE: The magnetic sheet should now be placed on top of the lid, so that it can be taken off while the substrates are still secure in the stack, thus avoiding damage to the substrates.
This video demonstrates how to load the high density OFET stack typically used to thermally evaporate (vacuum deposit) source-drain contacts. The video shows the below steps:
- Loading the interchangeable source-drain masks into the lower support (this is combined with the substrate holder).
- Loading the substrate
- Adding the magnetic sheet
- Screwing the lid on.
Learn more and get started with high density OFETs
The high density OFET fabrication system makes it simpler and quicker to make and test a large number of devices for statistical and optimisation purposes. Find out more by contacting our OFET team.
The high density fabrication system has four different masks available to allow the fabrication of devices in any geometry (top/bottom gates and top/bottom source-drain). The diagrams below show the features on each of the individual masks as well as how they fit together on a substrate.
To the best of our knowledge the information provided here is accurate. However, Ossila assume no liability for the accuracy of this page. The values provided are typical at the time of manufacture and may vary over time and from batch to batch. All products are for laboratory and research and development use only, and may not be used for any other purpose including health care, military, pharmaceuticals, cosmetics, food, or commercial applications.