Vertical, organic, light‐emitting transistors (VOLETs) combine three of the four essential components of an active matrix lightemitting diode (AMOLED) pixel ‐ the drive transistor, the storage capacitor, and the OLED stack ‐ into a single, highly‐stable, selfemissive structure. VOLETs can be manufactured on amorphous silicon (a‐Si) thin‐film transistor (TFT) backplanes to enable lowcost AMOLED displays with improved brightness and lifetime characteristics. We report on the current status of VOLET development and prospective impact on the active‐matrix display industry.

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-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 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.

SID Symposium Digest of Technical PapersVolume 53, Issue S1 p. 149-149 Technical Sessions: Session 14: Printed TFT & Novel Application of Printing Process (Printed Display) 14.2: Invited Paper: Outlook for Low Cost Printed Active-Matrix Light-Emitting Displays Enabled by Vertical Light-Emitting Transistor Technology Svetlana Vasilyeva, Svetlana Vasilyeva Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorXiao Chen, Xiao Chen Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorAndrew Rinzler, Andrew Rinzler University of Florida, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorMax Lemaitre, Max Lemaitre Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorBo Liu, Bo Liu Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this author Svetlana Vasilyeva, Svetlana Vasilyeva Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorXiao Chen, Xiao Chen Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorAndrew Rinzler, Andrew Rinzler University of Florida, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorMax Lemaitre, Max Lemaitre Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this authorBo Liu, Bo Liu Mattrix Technologies, Gainesville, Florida, 32601 U.S.A.Search for more papers by this author First published: 17 October 2022 https://doi.org/10.1002/sdtp.15876AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. References 1 M. A. McCarthy, B. Liu et. al. and A. G. Rinzler, Science, 332, p. 570 (2011). 2 B. Liu, M. A. McCarthy et. al. and A. G. Rinzler, Proceedings of the International Display Workshops, IDW ‘17, AMD6-1 (2017). 3 J. Lee, L Yu, et. al. and X. Lin, SID’20 Technical Digest, vol. 51, p. 508 (2020). 4 X. Guo, L Han, Y. Huang and W. Tang, SID’21 Technical Digest, vol. 52, p. 9 (2021). Volume53, IssueS1International Conference on Display Technology 2022 (Volume 53, Issue S1)October 2022Pages 149-149 ReferencesRelatedInformation

By combining three key components in an AMOLED display pixel: the drive transistor, the storage capacitor, and the OLED stack into a single, gate voltage controlled, light-emitting element, the vertical organic light emitting transistor (VOLET) works together with low-cost, mature TFT technology to enable high performance AMOLED display panels that can be mass produced on fully depreciated LCD lines.

We present the first display panels exploiting the nVerPix CN-VOLET technology that reduces the pixel circuit of the conventional AMOLED display to two discrete components: the switching transistor and the CN-VOLET. This permits high aperture ratio bottom emission displays—as high as 70% here— and greatly simplifies the manufacturing. Mono-color QVGA AMOLED displays (6.4 cm diagonal) playing video will be shown.

AbstractA new architecture light emitting transistor combining the drive transistor, storage capacitor and light emitter into a single device promises to greatly reduce AMOLED manufacturing costs by dramatically reducing the backplane circuit complexity. Here we demonstrate device operation at 60 Hz using only a switching transistor and show remarkable stability under bias stress, despite use of an organic channel.

A novel method for determination of trace amounts of microorganism populations in solution was developed by using a multiwalled carbon nanotube (MWNT) modified glassy carbon electrode and square wave voltammetry (SWV). The simultaneous combination of MWNT and SWV allowed the electrochemical signal of electro-active materials in Escherichia coli O157:H7 (E. coli) to be dramatically amplified. Compared with a bare glassy carbon electrode, the MWNT-modified glassy carbon electrode showed catalytic properties in the oxidation of electro-active materials on cell surfaces. Moreover, SWV was proved to be more sensitive than cyclic voltammetry (CV) for investigation of the electrochemical behavior of cells. In this paper, a linear relationship was obtained between the SWV peak current and the cell concentration in the range 2×102–2×108cellmL−1 with a detection limit of 2×102cellmL−1. The effect of antibiotic drug Gentamycin Sulfate injection (GSI) on the growth of E. coli was also investigated.

N-channel carbon nanotube enabled vertical field effect transistors (CN-VFETs) exploiting a solution deposited ZnO nanoparticle thin film as the channel material are demonstrated. Transistor performance benefits from a thermal anneal followed by an oxygen plasma treatment. The devices exhibit on/off ratios approaching 104 with output current densities exceeding 60 mA/cm2. Combined with p-channel organic CN-VFETs, the solution based processing could allow for the development of low-cost complementary circuits.

An improved process for graphene transfer was used to demonstrate high performance graphene enabled vertical organic field effect transistors (G-VFETs). The process reduces disorder and eliminates the polymeric residue that typically plagues transferred films. The method also allows for purposely creating pores in the graphene of a controlled areal density. Transconductance observed in G-VFETs fabricated with a continuous (pore-free) graphene source electrode is attributed to modulation of the contact barrier height between the graphene and organic semiconductor due to a gate field induced Fermi level shift in the low density of electronic-states graphene electrode. Pores introduced in the graphene source electrode are shown to boost the G-VFET performance, which scales with the areal pore density taking advantage of both barrier height lowering and tunnel barrier thinning. Devices with areal pore densities of 20% exhibit on/off ratios and output current densities exceeding 10(6) and 200 mA/cm(2), respectively, at drain voltages below 5 V.

The large current densities attained by carbon nanotube enabled vertical field effect transistors using crystalline organic channel materials are somewhat unexpected given the known large anisotropy in the mobility of crystalline organics and their conventional ordering on dielectric surfaces which tends to orient their high mobility axes parallel to the surface. This seeming contradiction is resolved by the finding that the nanotubes induce a molecular ordering that reorients the high mobility axes to favor current flow in a direction perpendicular to the substrate surface.

We exploit the low density of electronic states in single wall carbon nanotubes to demonstrate active, electronic modulation of their Fermi level offset relative to n-type silicon in a nanotube-Si (metal-semiconductor) Schottky junction solar cell. Electronic modulation of the Fermi level offset, the junction interface dipole and a field developed across the depletion layer modifies the built-in potential in the device and its power generation characteristics. As produced (before modulation) devices exhibit ∼8.5% power conversion efficiency (PCE). With active modulation the PCE is continuously and reversibly changed from 4 to 11%.