Preparing to seal the device - UV cure epoxy. This stuff is great. Apply and use UV light, hard in 6 seconds, intended for displays. Very expensive. My stock of it has unfortunately expired as of December, but it still works great.

A generous boundary of epoxy is applied to the cathode slide.

This serves two purposes:
1) To seal off the device from additional moisture (OLEDs hate water)
2) As an insulator (a spacer). We don't want the ITO glass of the cathode side to touch the materials on the anode side directly - indium-tin oxide has a high work function, so we'd effectively short the device out. There is enough gallium-indium-tin eutectic here to fill the vertical gap that the epoxy will create.

Now that the anode side has heated long enough, the PEDOT:PSS layer is done, any remaining water from the deposition has hopefully evaporated, and we can apply our active layer - the light emitting polymer. This material(MEH-PPV) is suspended in Toluene.

Spin coating the MEH-PPV over the PEDOT:PSS layer on the anode side.

Heat the anode side again to dissipate any remaining solvent. This step is done carefully - too much heat and the chemical composition of the active layer (the MEH-PPV) can change, ruining the device. This is done at 140C for 2-3 minutes.

Cathode and Anode sides, ready to be combined.

Applying UV. I use a violet laser instead of a fluorescent UV light. I had been using an EPROM eraser from China, but it didn't work well with the glue. Using the laser I can trace the epoxy boundary a few times and it's completely dry. The active layer is fluorescing green in response to the laser in this photo.

Completed device, ready to be tested.

When I was joining the two sides, I accidentally slid the slides together a bit, causing a scratch on the anode side - you can see the liquid metal completely touches the other side. Thankfully its work function is low and the rest of the device works.

Closeup photo.