Low-Voltage, Low-Power, Organic Light-Emitting Transistors for Active Matrix Displays

Abstract

Intrinsic nonuniformity in the polycrystalline-silicon backplane transistors of active matrix organic light-emitting diode displays severely limits display size. Organic semiconductors might provide an alternative, but their mobility remains too low to be useful in the conventional thin-film transistor design. Here we demonstrate an organic channel light-emitting transistor operating at low voltage, with low power dissipation, and high aperture ratio, in the three primary colors. The high level of performance is enabled by a single-wall carbon nanotube network source electrode that permits integration of the drive transistor and the light emitter into an efficient single stacked device. The performance demonstrated is comparable to that of polycrystalline-silicon backplane transistor-driven display pixels.

Ultralow-voltage Auger-electron-stimulated organic light-emitting diodes

“…[1][2][3][4] In the past few decades, significant efforts have been devoted to maximize device efficiency through new materials combined with innovation in device structures, such as the development of phosphorescent emitters, 5,6 thermally activated delayed fluorescent emitters, 7,8 guesthost structure, 9,10 cohost structure, 11,12 p-i-n structure, 3,13 and a simple device architecture, 14 etc. So far, OLEDs have reached efficiencies on par with the traditional inorganic light-emitting diodes.…”

“…15,16 Even in the most advanced OLEDs, however, operating voltages are still higher than or close to the HOMO-LUMO energy gaps of emitter molecules. 1,3,14 Recently, a new type of OLED involving ballistic Auger-electron injection at organic heterojunctions has been developed. This type of OLED has operating voltages well below the HOMO-LUMO energy gaps of the emitter molecules; i.e., the output photon energies are higher than the input electrical energies.…”

Hole mobility in thermally evaporated pentacene: Morphological and directional dependence

“…1,4,15-21 So far, however, only a few studies concerned the transport perpendicular to the a-b plane, [9][10][11]22 as transport in this direction has never been of much interest in real devices. With the development of vertical transistor structures, [23][24][25][26][27][28][29] however, which may use pentacene or pentacenelike materials, a more complete understanding of the hole mobility in pentacene and its dependence on film morphology are required, as many of the pentacene VOFETs (Vertical Organic Field-Effect Transistors) presented to date rely on transport both in and out of the a-b plane. 23,24,[28][29][30] In this contribution, we investigate the effective hole mobility of pentacene, both in and out of the a-b plane, and demonstrate that the effects of morphology established for in-plane transport also play a significant role for out-of-plane transport.…”

Photo-Crosslinking of Pendent Uracil Units Provides Supramolecular Hole Injection/Transport Conducting Polymers for Highly Efficient Light-Emitting Diodes

“…Organic light-emitting diodes (OLEDs) and polymer light-emitting diodes (PLEDs) are among the most promising technologies for use in next-generation light sources and flat-panel displays, because they can be prepared over large areas with light weights and can be operated with rapid responses, low power consumption, and wide viewing angles [1][2][3][4]. High-efficiency LED devices typically feature one or more organic layers-namely, the hole-injection/transport layer (HITL), the electron-emitting layer (EML), and/or the electron-injection/transport layer (EITL)-sandwiched between the two electrodes.…”