Specifications

Fabrication

Substrates ａnd cleaning

• Pixelated Cathode substrates (S171) or Photovoltaic (8 Pixel) Substrates
• 5 minutes sonication in hot 1% Hellmanex III
• 1x boiling DI dump rinse, 1x cold dump rinse
• 5 minutes sonication in warm IPA
• 2x DI cold dump rinse
• Stored in DI for 1hr
• 5 minutes sonication in hot 10% NaOH solution
• 2x DI dump rinse
• N2 blow dry

PEDOT:PSS

• PEDOT:PSS (AI 4083 PEDOT:PSS) filtered through a 0.45 µm PES filter (C2009S1)
• Spin on heated substrates at 6000 rpm for 30s
• Bake at 130°C after spin cast
• Note that the cathode strip was not wiped clean, this is to allow a consistent perovskite layer on
• Substrates held at a temperature of 90°C for spin casting

Active layer solution

• Old stock solution (2 weeks old) of MAI:PbCl2 (3:1 molar ratio) made at a concentration 664 mg/ml in DMF
  • Heated for approx. 3 hrs at 70°C
• Old stock solution of PC70BM, 50 mg/ml in CB
  • Heated for approx. 4 hrs at 70°C with stir bar

Active layers

• Devices spun onto hot substrate at 5000 rpm using 25 µl dynamic dispense for 30s
• Placed immediately onto hotplate at 90°C for 2 hrs
• Cathode wipe with dry cotton bud once all substrates were spun
• Films started with a bright yellow colour
• Changed to a dark grey colour during thermal annealing process
• Transferred to a N2 glove box
• PCBM layer was spun at 1000 rpm for 30s, 20 µl dynamic dispense
• CB cathode wipe

Evaporation

Left in vacuum chamber overnight ａnd evaporated with the below parameters.

• 5 nm Ca at 0.2 Å/s
• 100 nm Al at 1.5 Å/s
• Deposition pressure 1e-6 mbar

Encapsulation

• As standard using Ossila EE1, 30 mins UV in MEGA LV101