Growth of organic crystalline thin films with strong second-order nonlinearity for integrated optics

We demonstrate the growth of highly nonlinear crystalline thin films of N-benzyl-2-methyl-4-nitroaniline (BNA) with a controllable crystal orientation. These films are obtained by crystallizing the material in a temperature gradient. Through second-harmonic generation experiments at a fundamental wavelength of 1550 nm, we found a second-order nonlinearity of (153 ± 70) pm/V. This greatly exceeds the value of 54 pm/V for LiNbO3, the benchmark nonlinear crystal. Moreover, the crystalline films are grown on amorphous substrates with processing temperatures not exceeding 115°C, making them suitable for back-end photonic integration on a CMOS chip. We envisage the growth of BNA crystalline films on silicon nitride photonic integrated circuits, where a strong second-order nonlinearity is lacking

Chapter Interlayer Processing in Active Matrix OLED Displays

Medical genetic

Energy Level Tuning of Non-fullerene Acceptors in Organic Solar Cells

This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Journal of the American Chemical Society , copyright © American Chemical Society after peer review. To access the final edited and published work, see http://pubs.acs.org/doi/abs/10.1021/jacs.5b02808The use of non-fullerene acceptors in organic photovoltaic devices could lead to enhanced efficiencies due to increased open-circuit voltages (VOC) and improved absorption of solar light. Here we systematically investigate planar heterojunction devices comprising peripherally substituted subphthalocyanines as acceptor, and correlate device performance with heterojunction energetics. Due to a balance between VOC and photocurrent, tuning of the interface energy gap is necessary to optimize power conversion efficiency in these devices. In addition, we explore the role of the charge transport layers in the device architecture. It is found that non-fullerene acceptors require adjusted buffer layers with aligned electron transport levels to enable efficient charge extraction, while the insertion of an exciton blocking layer at the anode interface further boosts photocurrent generation. These adjustments result in a planar heterojunction OPV device with 6.9% efficiency and a VOC above 1 V.The research leading to these results has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement 287818 of the X10D project and from the European Community’s ERC Advanced Grant # 320680 (EPOS CRYSTALLI). This work is also supported by the Spanish MINECO (CTQ-2014-52869-P) and Comunidad de Madrid (S2013/MIT-2841, FOTOCARBON

Interlayer Processing in Active Matrix OLED Displays

Medical genetic

Integration of highly crystalline C8-BTBT thin-films into simple logic gates and circuits

Highly crystalline organic thin films possess the charge carrier mobilities needed for high-performance, low-cost flexible electronics. However, only few reports exist that show the integration of these films into short-channel organic circuits. This work describes the integration of highly crystalline layers of the thermally and chemically fragile small molecule C8-BTBT. Thin films of this material are processed by a combination of zone-casting and homoepitaxial vacuum evaporation and display an average charge carrier mobility of 7.5 cm2/V in long channel transistors. The integration of these films into a circuit technology based on a 5 μm channel-length bottom-gate bottom-contact transistor topology results in inverters with gains up to 40 as well as a robust 19-stage ring oscillator. This circuit requires the simultaneous operation of 80 TFTs and displays a stage delay of 40 μs, resulting in an operating frequency of 630 Hz at an operating voltage of 10 V. With the help of circuit modelling, we quantify the relationship between the speed of ring oscillators and the contact resistance of individual transistors. Indeed, the successful integration of highly-crystalline layers with high intrinsic mobility stresses the need for advances in contact engineering

Organic RFID Tags

status: publishe

Low-temperature and low-voltage, solution-processed metal oxide n-TFTs and flexible circuitry on large-area polyimide foil

In this article, we report on high-performance solution-based n-type metal oxide TFTs processed directly on polyimide foil and annealed at 250 °C. Saturation mobilities exceeding 2 cm²/(Vs) and Ion/Ioff ratios beyond 108 have been achieved. Using these oxide n-TFTs, fast and low-voltage flexible circuitry is presented. Furthermore, a complete 8-bit RFID transponder chip, containing 294 oxide n-TFTs has been fabricated. Both high-speed and low-voltage operation makes the presented oxide n-TFT technology suited for both the pixel driving and embedded line-drive circuitry at the borders of flexible AMOLED displays

AMOLED Displays with In-Pixel Photodetector

The focus of this chapter is to consider additional functionalities beyond the regular display function of an active matrix organic light-emitting diode (AMOLED) display. We will discuss how to improve the resolution of the array with OLED lithography pushing to AR/VR standards. Also, the chapter will give an insight into pixel design and layout with a strong focus on high resolution, enabling open areas in pixels for additional functionalities. An example of such additional functionalities would be to include a photodetector in pixel, requiring the need to include in-panel TFT readout at the peripherals of the full-display sensor array for applications such as finger and palmprint sensing

Sprühverfahren verbilligen die Fertigung Polymer-basierter organischer Solarzellen: Solarzellen von der Rolle

status: publishe