High photosensitivity and wide operation voltage in two-dimensional CdS nano-crystal layer embedded a-InGaZnO hybrid phototransistors

Artificially Fabricated Subgap States for Visible-Light Absorption in Indium–Gallium–Zinc Oxide Phototransistor with Solution-Processed Oxide Absorption Layer

“…Similarly, under green laser illumination, the IGZO phototransistors with SAL annealed at 200°C showed superior PR, PS, and D * (206 A/W, 8.34 × 10 6 , and 4.23 × 10 11 Jones, respectively). These optoelectronic characteristics are also superior to those of the previous IGZO phototransistors, as shown in Table S2. ,,,− The variation in each parameter according to the gate voltage under red and green laser illuminations are summarized in Figure S3. These results indicated that the operational voltage range for light detection was further increased by stacking the SALs, resulting in a stable operation.…”

“…Oxide semiconductors have been researched and commercialized as a channel material of thin-film transistors (TFTs) in the display industry due to their high transparency, high field effect mobility, low off-state current, and capability of large-area deposition. − Recently, studies on oxide semiconductors have been conducted for next-generation electronic devices, going beyond the display backplane by exploiting these advantages. For instance, there are studies about biosensor using high reactivity of back channel surfaces, neuromorphic devices using a persistent photocurrent (PPC) under high photon energy conditions, and phototransistors using a low dark current and high photosensitivity (PS). − However, oxide-based phototransistors have a limited detection wavelength range (blue or UV) light due to the wide band gap of the oxide semiconductors (>3 eV). − Therefore, various studies have been conducted to detect the full range of visible light (400–700 nm) by stacking additional absorption layers such as quantum dots, two-dimensional materials, organic materials, and metal nanoparticles. − However, these absorption layers have disadvantages such as requirement for complex fabrication processes, poor uniformity, interface traps between channel and absorption layers, and vulnerability to the external environment. To overcome these issues, a few studies have recently been conducted on phototransistors composed only of oxide semiconductors. , However, electrical characteristics of these phototransistors are degraded in the dark because the channel layer is identical to the light absorption layer.…”

A Review of Phototransistors Using Metal Oxide Semiconductors: Research Progress and Future Directions

“…applied CdS to an IGZO phototransistor as a nano‐crystal‐type absorption layer. [ 100 ] In particular, in this study, the characteristics of the phototransistor according to the location of the CdS absorption layer were compared. Thus, the device structure with the CdS absorption layer located in the middle of the IGZO channel layer, as shown in Figure 9d, exhibited higher light absorption efficiency than those below or above the IGZO layer.…”

IGZO/CsPbBr3-Nanoparticles/IGZO Neuromorphic Phototransistors and Their Optoelectronic Coupling Applications

“…Recently, increasing attention has been paid to brain-inspired neuromorphic systems that have great advantages of efficiency and energy saving in processing complex and unstructured problems. − Neuromorphic devices triggered by various kinds of stimuli (such as electrical, − optical, − chemical, pressure signals . and so on) have been reported to emulate abundant synaptic functions in biological systems.…”