Vacuum processed large area doped thin-film crystals: A new approach for high-performance organic electronics

Rubrene single crystal domains with hundreds of micrometers size fully covering different substrates are achieved by thermal annealing of evaporated amorphous thin films with the help of a thin glassy underlayer. The sufficiently large energy level offset of the underlayer material and rubrene enables high performance staggered bottom gate rubrene crystalline transistors with maximum field-effect linear mobility over 5 cm(2)V(-1)s(-1) (mu(Avg) = 4.35 +/- 0.76 cm(2)V(-1)s(-1)) for short channel devices of 20 mu m, comparable to high quality rubrene bulk single crystals. Moreover, since molecular dopants up to several mole percent can be incorporated into the single crystals with a minimal disturbance of the lattice, the contact resistance of the transistors is significantly reduced to around 1 kOhm.cm by contact doping via adlayer epitaxy of p-type doped rubrene. Our results pave the way for novel high-performance organic electronics using crystalline active materials with mass-production compatible deposition techniques. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Rubrene single crystal domains with hundreds of micrometers size covering different substrates are achieved by thermal annealing and the assistance of a thin glassy underlayer, enabling high-performance rubrene crystalline transistors. The contact resistance of the transistors is significantly reduced through doping techniques, paving the way for novel high-performance organic electronics using crystalline active materials.