Opportunities for cost-effective manufacturing of fully printed high performance displays enabled by vertical light-emitting transistor pixels

Abstract

With the Vertical Organic Light-Emitting Transistor (VOLET), we introduce a promising solution that could significantly benefit the manufacturing of displays, accelerating the wide adoption of flexible and printed electronics. The VOLET – like conventional, lateral channel, organic thin film transistors (OTFTs) – is compatible with a variety of printing techniques as well as flexible substrates and low-temperature processing. In combination these devices will enable a more cost-effective approach to mass-production that can dramatically extend the market potential of active-matrix organic light-emitting diode (AMOLED) displays. In this paper we discuss the prospects that AMOLED presents for the future of the display market, with a focus on the innovative VOLET device architecture. We assess how the integration of this device into active-matrix displays can contribute to the long range sustained competitiveness of AMOLED technology. We review recent progress in mass production techniques for printed electronics, with a particular emphasis on large-scale carbon nanotube (CNT) material deposition. Finally, we explore the prospects for fully printed active-matrix light-emitting displays, including a review of high-performance printed components whose integration could facilitate the mass production of low-cost, high-performance, VOLET based AMOLEDs.

77‐1: Invited Paper: Towards Commercialization of Vertical, Organic Light‐emittingTransistors for Active‐Matrix Displays

“…Additionally, as the VFET/VOLET technology is compatible with transparent and flexible form factors, roll-to-roll printing techniques, and various light-emitting materials, it has potential to find application in a variety of display formats, including transparent displays, microLEDs, direct-view mixed-reality displays, and automotive displays/lighting. 7…”

“…When the OLED layers are inserted between the channel and the drain, the VFET device could be turned into a novel vertical organic light-emitting transistor (VOLET, Figure 1 b). [3][4][5][6][7][8][9] The VOLET enables the drive circuitry and OLED layers to be combined into a vertical stack, integrating the driving transistor, OLED and storage capacitor (by the intrinsic capacitance of the CNT source electrode) into a single device and reducing the pixel component count to two: a switching transistor and the VOLET. The vertical orientation provides several benefits for the display pixel.…”