R. Taguchi

Bio: R. Taguchi is an academic researcher from Keio University. The author has contributed to research in topics: Electrochromism & Phthalocyanine. The author has an hindex of 1, co-authored 1 publications receiving 11 citations.

Heat treatment effect on the single oscillator parameters and optical band gap of an organic thin film

Abstract: The effect of heat treatment on the optical band gap and refractive index dispersion of 2,9,16,23-tetraneopentoxyphthalocyaninato zinc(II) thin film has been investigated. The absorption edge with increasing annealing temperature was shifted to the lower energy side and fundamental absorption edge is formed by a direct allowed transition. The refractive index and dispersion parameters E o and E d of the thin film were determined. The obtained results show that the film is suitable to change refractive index and oscillator parameters by heat treatment.

Microelectronic properties of organic Schottky diodes based on MgPc for solar cell applications

Abstract: The magnesium phthalocyanine (MgPc) based Schottky diodes are fabricated using four inorganic semiconductors ( n -GaAs, n -Si, p -InP, p -Si)by the spin-coating process at 2000 rpm for 1 min. Their microelectronic and photoelectrical parameters are investigated from the current-voltage I–V characteristics measurements at room temperature in dark and under light. The ln I–V plots, Cheung and Norde methods are used to extract the MgPc based Schottky diodes parameters in dark, including ideality factor (n), barrier height (Φ b ), series resistance (R s ) and the obtained values are compared. The MgPc/n-Si showed excellent n of 1.1 which is very closer to ideal Schottky diode behavior, high Ф b of 0.98 eV and low series resistance of 237.77 Ω in contrast MgPc/p-Si showed non-ideal Schottky diode behavior with n of 2.42 and high series resistance of 1.92 × 10 3 Ω. The MgPc/p-InP exhibited photovoltaic behavior with excellent J SC of 3.11 × 10 3 mA/cm 2 and a photosensitivity of 30.46. The I–V forward bias in log scale have been investigated to survey the dominated conduction mechanism. This study reviews thecrucial effect of (p and n) type conductivity substrates on the electrical parameters of organic MgPc Schottky diodes for the use in such organic photovoltaic applications.

Electrical characterization of the organic semiconductor Ag/CuPc/Au Schottky diode

Abstract: This paper reports on the fabrication and investigation of a surface-type organic semiconductor copper phthalocyanine (CuPc) based diode. A thin film of CuPc of thickness 100 nm was thermally sublimed onto a glass substrate with preliminary deposited metallic electrodes to form a surface-type Ag/CuPc/Au Schottky diode. The current-voltage characteristics were measured at room temperature under dark conditions. The barrier height was calculated as 1.05 eV The values of mobility and conductivity was found to be 1.74 × 10−9 cm2 (V · s) and 5.5 × 10−6 Ω−1 · cm−1, respectively. At low voltages the device showed ohmic conduction and the space charge limited current conduction mechanisms were dominated at higher voltages.

Electrical characterization of the ITO/NiPc/PEDOT : PSS junction diode

Abstract: This paper reports on the fabrication and characterization of an ITO/NiPc/PEDOT?:?PSS junction diode. A thin film of nickel phthalocyanine (NiPc) was deposited by the thermal vacuum deposition method on indium tin oxide (ITO) used as a substrate. The current?voltage characteristics of the diode were measured at room temperature under dark condition and showed rectifying behaviour. The values of several electrical parameters such as ideality factor, barrier height, conductivity, and series and shunt resistances were calculated.

A novel device behavior of Ag/MgPc/n-GaAs/Au-Ge organic based Schottky diode

Abstract: The fabricated Ag/MgPc/n-GaAs/Au-Ge Schottky diode is investigated by using the electrical parameters obtained from the current–voltage ( I – V ) characteristics measurement at room temperature under dark and light conditions. The Cheung and Norde methods with the I–V characteristics are used to calculate and extract the Schottky diode parameters under dark and light (100 mW/cm 2 ) comprising ideality factor n, barrier height ( Φ b ), series resistance ( R S ) short circuit current density ( J SC ) and open circuit voltage ( V OC ) are respectively found to be 3.64, 0.53 eV, 32.67 Ω, 1.129 mA/cm 2 and 0.35 V. It is seen that the value of R S and J SC are low compared to the literature work which is ascribed to the configuration of Schottky diode structure such as substrate, front and back contacts. Here, we review the contribution to the understanding of magnesium phthalocyanine (MgPc) based Schottky diode for the organic microelectronics applications.