The Experts below are selected from a list of 2196 Experts worldwide ranked by ideXlab platform

Shizuo Tokito - One of the best experts on this subject based on the ideXlab platform.

  • compact organic complementary d type Flip Flop Circuits fabricated with inkjet printing
    Advanced electronic materials, 2017
    Co-Authors: Kazuma Hayasaka, Hiroyuki Matsui, Yasunori Takeda, Rei Shiwaku, Yasuhiro Tanaka, Takeo Shiba, Daisuke Kumaki, Shizuo Tokito
    Abstract:

    Organic thin-film transistors (OTFTs) have received significant consideration in recent years for potential deployment in low-cost and large-area printed electronics. D-type Flip-Flop (D-FF) Circuits are one of the most important logic gates for data processing and storage in such applications. Previous work has reported on NAND-based organic D-FF Circuits. Although the demonstrated printed Circuits exhibit low voltage operation at 10 V, each D-FF circuit requires 34 TFT devices and occupies an area of 192 mm2 per D-FF circuit. This paper demonstrates inkjet-printed organic D-FF Circuits with a compact circuit design using clocked inverters and transmission gates and compares the occupied area and the circuit performance with those of NAND-based organic D-FF Circuits. The compact organic D-FF Circuits require only 18 OTFT devices, and can use 60% less area than NAND-based organic D-FF Circuits fabricated by the same process. In addition, the compact organic D-FF Circuits exhibit a shorter propagation delay time than the NAND-based D-FF Circuits. The mechanism for the shortened delay time will be discussed in detail, based on SPICE simulations. These results demonstrate the high potential of these compact organic D-FF Circuits in printable electronics.

  • fabrication of ultra thin printed organic tft cmos logic Circuits optimized for low voltage wearable sensor applications
    Scientific Reports, 2016
    Co-Authors: Yasunori Takeda, Kazuma Hayasaka, Rei Shiwaku, Takeo Shiba, Daisuke Kumaki, Koji Yokosawa, Masashi Mamada, Kenjiro Fukuda, Shizuo Tokito
    Abstract:

    Ultrathin electronic Circuits that can be manufactured by using conventional printing technologies are key elements necessary to realize wearable health sensors and next-generation flexible electronic devices. Due to their low level of power consumption, complementary (CMOS) Circuits using both types of semiconductors can be easily employed in wireless devices. Here, we describe ultrathin CMOS logic Circuits, for which not only the source/drain electrodes but also the semiconductor layers were printed. Both p-type and n-type organic thin film transistor devices were employed in a D-Flip Flop circuit in the newly developed stacked structure and exhibited excellent electrical characteristics, including good carrier mobilities of 0.34 and 0.21 cm2 V−1 sec−1 and threshold voltages of nearly 0 V with low operating voltages. These printed organic CMOS D-Flip Flop Circuits exhibit operating frequencies of 75 Hz and demonstrate great potential for flexible and printed electronics technology, particularly for wearable sensor applications with wireless connectivity.

N Pleros - One of the best experts on this subject based on the ideXlab platform.

  • memory speed analysis of optical t Flip Flop Circuits based on an soa mzi and a feedback loop
    International Conference on Photonics in Switching, 2012
    Co-Authors: D Fitsios, A Miliou, N Pleros, C Vagionas, G T Kanellos
    Abstract:

    We demonstrate a frequency-domain transfer function analysis for optical T-Flip-Flops relying on feedback loops, along with experimental verification. Our analysis confirms experimental results, showing that optimized circuit design can enable optical T-Flip-Flop memory speeds higher than 40GHz.

  • memory speed analysis of optical ram and optical Flip Flop Circuits based on coupled soa mzi gates
    IEEE Journal of Selected Topics in Quantum Electronics, 2012
    Co-Authors: D Fitsios, K Vyrsokinos, A Miliou, N Pleros
    Abstract:

    We demonstrate analytical frequency-domain transfer function expressions for an optical random access memory (RAM) cell that employs two SOA-based ON/OFF switches and two coupled SOA-MZI gates forming an optical Flip-Flop. Our theoretical model relies on first-order perturbation theory approximations applied for the first time to coupled optical switching structures, resulting to an optical RAM cell frequency response that allows for a qualitative and quantitative analysis of optical RAM memory speed and performance characteristics and their dependence on certain RAM cell device parameters. We show that the transfer function of an optical RAM cell and its incorporated Flip-Flop device exhibits periodic resonance frequencies resembling the behavior of optical ring resonator configurations. Its free spectral range is mainly dictated by the length of the waveguide that enables the coupling of the two SOA-MZI gates, yielding this coupling length as the dominant memory speed determining factor. The obtained results are in close agreement with experimental observations, demonstrating that optimized RAM cell designs with waveguide coupling lengths lower than 5 mm can enable RAM operation at memory speeds well beyond 40 GHz.

Jiro Yoshida - One of the best experts on this subject based on the ideXlab platform.

  • YBaCuO/Co-doped PrBaCuO/YBaCuO ramp-edge junctions and their application to Flip–Flop Circuits
    Applied Superconductivity, 1999
    Co-Authors: S. Inoue, Tatsunori Hashimoto, Toshihiko Nagano, Jiro Yoshida
    Abstract:

    Abstract We fabricated YBa2Cu3O7−x/PrBa2Cu2.8Co0.2O7−y/YBa2Cu3O7−x ramp-edge Josephson junctions and measured their current–voltage (I–V) characteristics. Critical current (Ic) and conductance (G) were evaluated as a function of the barrier layer thickness, and both of them exhibited a nearly exponential dependence. The decay parameters for Ic and G were estimated to be 1.1 and 1.5 nm, respectively. We also examined superconducting quantum interference devices (SQUIDs) using this type of junction as a preliminary test for realizing oxide superconductive integrated Circuits with high-speed operation. DC SQUIDs with direct-coupling control lines and no ground plane were fabricated and their loop inductance was evaluated. The obtained SQUID inductance ranged from 8 to 38 pH for a 4-μm-wide, 3- to 12-μm-long hole in a rectangular SQUID loop. In addition, a Flip–Flop circuit based on such a dc SQUID was fabricated. Both flux trapping and flux detrapping in the SQUID loop hole were confirmed when 1-ms-wide current pulses were injected into the SQUID loop.

  • ybacuo co doped prbacuo ybacuo ramp edge junctions and their application to Flip Flop Circuits
    Applied Superconductivity, 1999
    Co-Authors: S. Inoue, Tatsunori Hashimoto, Toshihiko Nagano, Jiro Yoshida
    Abstract:

    Abstract We fabricated YBa2Cu3O7−x/PrBa2Cu2.8Co0.2O7−y/YBa2Cu3O7−x ramp-edge Josephson junctions and measured their current–voltage (I–V) characteristics. Critical current (Ic) and conductance (G) were evaluated as a function of the barrier layer thickness, and both of them exhibited a nearly exponential dependence. The decay parameters for Ic and G were estimated to be 1.1 and 1.5 nm, respectively. We also examined superconducting quantum interference devices (SQUIDs) using this type of junction as a preliminary test for realizing oxide superconductive integrated Circuits with high-speed operation. DC SQUIDs with direct-coupling control lines and no ground plane were fabricated and their loop inductance was evaluated. The obtained SQUID inductance ranged from 8 to 38 pH for a 4-μm-wide, 3- to 12-μm-long hole in a rectangular SQUID loop. In addition, a Flip–Flop circuit based on such a dc SQUID was fabricated. Both flux trapping and flux detrapping in the SQUID loop hole were confirmed when 1-ms-wide current pulses were injected into the SQUID loop.

D Fitsios - One of the best experts on this subject based on the ideXlab platform.

  • memory speed analysis of optical t Flip Flop Circuits based on an soa mzi and a feedback loop
    International Conference on Photonics in Switching, 2012
    Co-Authors: D Fitsios, A Miliou, N Pleros, C Vagionas, G T Kanellos
    Abstract:

    We demonstrate a frequency-domain transfer function analysis for optical T-Flip-Flops relying on feedback loops, along with experimental verification. Our analysis confirms experimental results, showing that optimized circuit design can enable optical T-Flip-Flop memory speeds higher than 40GHz.

  • memory speed analysis of optical ram and optical Flip Flop Circuits based on coupled soa mzi gates
    IEEE Journal of Selected Topics in Quantum Electronics, 2012
    Co-Authors: D Fitsios, K Vyrsokinos, A Miliou, N Pleros
    Abstract:

    We demonstrate analytical frequency-domain transfer function expressions for an optical random access memory (RAM) cell that employs two SOA-based ON/OFF switches and two coupled SOA-MZI gates forming an optical Flip-Flop. Our theoretical model relies on first-order perturbation theory approximations applied for the first time to coupled optical switching structures, resulting to an optical RAM cell frequency response that allows for a qualitative and quantitative analysis of optical RAM memory speed and performance characteristics and their dependence on certain RAM cell device parameters. We show that the transfer function of an optical RAM cell and its incorporated Flip-Flop device exhibits periodic resonance frequencies resembling the behavior of optical ring resonator configurations. Its free spectral range is mainly dictated by the length of the waveguide that enables the coupling of the two SOA-MZI gates, yielding this coupling length as the dominant memory speed determining factor. The obtained results are in close agreement with experimental observations, demonstrating that optimized RAM cell designs with waveguide coupling lengths lower than 5 mm can enable RAM operation at memory speeds well beyond 40 GHz.

Yasunori Takeda - One of the best experts on this subject based on the ideXlab platform.

  • compact organic complementary d type Flip Flop Circuits fabricated with inkjet printing
    Advanced electronic materials, 2017
    Co-Authors: Kazuma Hayasaka, Hiroyuki Matsui, Yasunori Takeda, Rei Shiwaku, Yasuhiro Tanaka, Takeo Shiba, Daisuke Kumaki, Shizuo Tokito
    Abstract:

    Organic thin-film transistors (OTFTs) have received significant consideration in recent years for potential deployment in low-cost and large-area printed electronics. D-type Flip-Flop (D-FF) Circuits are one of the most important logic gates for data processing and storage in such applications. Previous work has reported on NAND-based organic D-FF Circuits. Although the demonstrated printed Circuits exhibit low voltage operation at 10 V, each D-FF circuit requires 34 TFT devices and occupies an area of 192 mm2 per D-FF circuit. This paper demonstrates inkjet-printed organic D-FF Circuits with a compact circuit design using clocked inverters and transmission gates and compares the occupied area and the circuit performance with those of NAND-based organic D-FF Circuits. The compact organic D-FF Circuits require only 18 OTFT devices, and can use 60% less area than NAND-based organic D-FF Circuits fabricated by the same process. In addition, the compact organic D-FF Circuits exhibit a shorter propagation delay time than the NAND-based D-FF Circuits. The mechanism for the shortened delay time will be discussed in detail, based on SPICE simulations. These results demonstrate the high potential of these compact organic D-FF Circuits in printable electronics.

  • fabrication of ultra thin printed organic tft cmos logic Circuits optimized for low voltage wearable sensor applications
    Scientific Reports, 2016
    Co-Authors: Yasunori Takeda, Kazuma Hayasaka, Rei Shiwaku, Takeo Shiba, Daisuke Kumaki, Koji Yokosawa, Masashi Mamada, Kenjiro Fukuda, Shizuo Tokito
    Abstract:

    Ultrathin electronic Circuits that can be manufactured by using conventional printing technologies are key elements necessary to realize wearable health sensors and next-generation flexible electronic devices. Due to their low level of power consumption, complementary (CMOS) Circuits using both types of semiconductors can be easily employed in wireless devices. Here, we describe ultrathin CMOS logic Circuits, for which not only the source/drain electrodes but also the semiconductor layers were printed. Both p-type and n-type organic thin film transistor devices were employed in a D-Flip Flop circuit in the newly developed stacked structure and exhibited excellent electrical characteristics, including good carrier mobilities of 0.34 and 0.21 cm2 V−1 sec−1 and threshold voltages of nearly 0 V with low operating voltages. These printed organic CMOS D-Flip Flop Circuits exhibit operating frequencies of 75 Hz and demonstrate great potential for flexible and printed electronics technology, particularly for wearable sensor applications with wireless connectivity.