Enhanced photocurrent in organic photodetectors by the tunneling effect of a hafnium oxide thin film as an electron blocking layer

Abstract

To achieve high detectivity of organic photodetectors (OPDs), we investigated hafnium oxide (HfO2) as an electron blocking layer in an attempt to obtain a low leakage current and high photocurrent by the tunneling effect.

NiOx nanoparticles obtained from hydrothermally treated NiC2O4 as an electron blocking layer for organic photodetectors

“…OPD performance depends on both its ability to block the dark current electrons and the generation of a high photocurrent to achieve high detectivity [40]. Under light exposure, a band alignment is formed at the active/blocking layer interface, which means the carriers can transport from the organic layer to the electrode side via the band-to-band tunneling with the help of the external field [21,41]. As shown in figure 1(d), photo-generated carriers were transported by the tunneling effect of nickel oxide and aluminum-doped zinc oxide under light exposure owing to the modulation of barrier height.…”

“…For OPDs, the preparation of a high-quality electron blocking layer (EBL) on organic semiconductor materials is the usual approach [20]. The EBL serves to block the dark current under a reverse bias and extracts photo-generated carriers from the active layer to the electrode [21]. PEDOT:PSS [poly (3,4ethylenedioxythiophene):poly(styrenesulfonate)] is typically used to transport hole carriers in devices [22][23][24][25].…”

Effect of silver doping on electrical characteristics of aluminum/HfO2/p-silicon metal-oxide-semiconductor devices

“…As device dimensions become smaller, leakage currents through the dielectric become more pronounced, resulting in power loss and reduced device efficiency. Hafnium oxide, with its superior insulating properties, helps alleviate these issues by reducing leakage currents and improving overall device performance [16][17][18].…”