Realization of In:ZnO/PEDOT:PSS based multifunctional device for ultraviolet (UV) light detection and resistive switching memory applications

Abstract

The present research reports on a hybrid multifunctional device for UV light detection and non-volatile resistive switching memory based on n-In:ZnO/poly 3,4-ethylene dioxythiophene:polystyrene sulfonate (PEDOT:PSS) junctions. Using a spray pyrolysis method, indium (1–5 at. %) doped ZnO thin films (IZO) were deposited on the pre-heated glass substrate. The structural analysis of IZO thin films shows that all the prepared samples exhibit a hexagonal wurtzite structure with preferential orientation along the (101) plane. The morphological analysis shows a uniform distribution of grains without any voids. The optical transmission spectra reveal that IZO thin films show higher transparency (>90%) in the visible region. With an optimum doping concentration of In (4 at. %), the deposited IZO thin films exhibit high carrier concentration and low electrical resistivity value of 4.58 × 1020 cm−3 and 4.01 × 10−2 Ω cm, respectively. The current–voltage (I–V), photoresponse, and resistive switching behavior of the fabricated n-IZO/PEDOT:PSS-based hybrid device was studied. Under an external reverse bias, the device exhibits a high photoresponsivity (R) value of 0.31 A/W and fast photoresponse switching speed with the measured rise and fall time of 0.08 and 1 s, respectively. It was proposed that the formation/rupture of both anionic and cationic conductive filaments plays a crucial role in the obtained resistive characteristics of the fabricated hybrid device.

Optimized Stoichiometry for CuCrO2 Thin Films as Hole Transparent Layer in PBDD4T-2F:PC70BM Organic Solar Cells

“…This polymeric material has been selected due to its solubility in water [ 5 ], which allows its synthesis through solution-based processes, and to its high transparency, around 90%. However, this polymer presents several disadvantages such as heterogeneous electrical properties [ 6 ], inefficient electron blocking function as proved by results from polymer light-emitting devices [ 7 ], with a Lowest Unoccupied Molecular Orbital (LUMO) at 3.5 eV [ 8 , 9 ] and a Highest Occupied Molecular Orbital (HOMO) around 5.2 eV [ 10 , 11 , 12 ]. This polymer is also characterized by a strong acidity, which promotes the corrosion of the Indium Tin Oxide (ITO) layer used as transparent electrode [ 13 , 14 , 15 ].…”

Bipolar resistive switching in Ag/VO2(B)/SiOx/n++Si RRAM

“…It notes that there is no RS behavior in Device D (see in figure 3), whose I-V feature is consistent with the I-V characteristic of n-type silicon [38]. The differences among four devices imply that Ag gel and VO 2 (B)/SiO x layer play a synergistic effect on bipolar RS behavior of the Device, the synergistic effect was observed in n-IZO/PEDOT:PSS based junction [39], where the formation of conductive filaments was attributed to the migration of both oxygen ions from IZO layers and Ag + ions from PEDOT:PSS layers. Although the RS of the oxide-based RRAM could also be caused by the formation of conductive filaments from oxygen ions [40,41], the role of the oxygen ions in device A may be weakened due to the SiOx layer and the formation of silver conducting filaments [11,34,42] is predominant in present study.…”

Impact of substrate temperature on NiO thin films for resistive switching memory (ReRAM) memory devices

“…In order to calculate the slope value under different bias voltage regions, the current-voltage (I-V) characteristics of the optimum fabricated ITO/NiO(375)Ag devices were re-plotted in a double logarithmic scale. Figure 7 The obtained linear bahaviour may be attributed to the injected charge carrier density from electrodes being less than that of thermally generated charge carriers [28]. In the positive voltage-bias HRS region, the obtained slope value is different for lower and higher bias regions.…”

“…In contrast, for the higher bias HRS region, the current-voltage (I -V) characteristics exhibit a non-linear behaviour with a calculated slope value of ∼ 2.4 and follow the Child's condition law (I ∝ V n , where n >1) [287]. The non-linear behaviour obtained may be attributed to the higher concentration of injected charge carriers than thermally generated charge carriers [28].…”

“…These conductive filaments are responsible for the switching between high resistance states (HRS) and low resistance states (LRS) of the fabricated ITO/NiO/Ag devices. Figures 8(a)-(c) shows a schematic diagram illustrating the formation and rupture of conductive paths between the silver (Ag) top and bottom (ITO) electrodes of the fabricated ITO/NiO/Ag RS devices [27,28]. The presence of nickel vacancy (V Ni ) and oxygen vacancy (V O ), defects was considered a native defect in NiO thin film layers.…”