Accurate Defect Density-of-State Extraction Based on Back-Channel Surface Potential Measurement for Solution-Processed Metal-Oxide Thin-Film Transistors

Effect of Back-Channel Surface on Reliability of Solution-Processed In0.51Ga0.15Zn0.34O Thin-Film Transistors with Thin Active Layer

“…In a previous study, we obtained the L D of IGZO TFT fabricated by the same process as approximately 30 nm. 12 Because the L D increases at lower carrier concentration, we concluded that the L D is longer than t IGZO under NBS, and the back-channel area can be strongly affected by V ST . Therefore, the ambient effect is the dominant mechanism under NBS, and the ΔV th can show different behavior under PBS and NBS.…”

“…Then, we investigated Δ V th along with N ads using 2D TCAD simulation. The μ FE of 1.5 cm 2 /V·s, the carrier concentration of 1 × 10 16 cm –3 , and the relative permittivity of IGZO of 3.25 were used, and other simulation parameters were set based on the previous reports. , The transfer curve was simulated as changing the fixed charge density ( Q f ). Figure a illustrates the simulated device schematic.…”

“…Therefore, the backchannel effect also needs to be considered when the solutionprocessed IGZO layer is thinner than the Debye length (L D ). 12 Herein, we investigated the V th instability of solutionprocessed In 0.51 Ga 0.15 Zn 0.34 O TFTs with the active layer thickness (t IGZO ) of approximately 10 nm. The ΔV th followed stretched-exponential and linear function under positive gate bias stress (PBS) and negative gate bias stress (NBS), respectively.…”

“…In terms of solution-processed TFTs, the degradation mechanism has not been intensively investigated, although many research groups have reported the degradation behavior and improvement methods. , Generally, the solution process results in a thinner active layer than the vacuum process. Therefore, the back-channel effect also needs to be considered when the solution-processed IGZO layer is thinner than the Debye length ( L D ) …”

Effective Evaluation Strategy Toward Low Temperature Solution-Processed Oxide Dielectrics for TFT Device

“…This indicates samples with dielectrics from ink-1 and ink-5 were of better quality. What's more, the attenuation for IGZO was sufficient for samples from ink-1 and ink-5 as it decayed to 1000mV after 2.5µs, while samples from ink-2 exhibited worse result with around 3000mV, corresponding to the long lifetime of photogenerated carriers caused by defects at the interface [26]. Decay curves provided valuable information on interface contact of IGZO/ZrO 2 .…”