Escalab 250 photoelectron spectrometer

The morphologies and surface structures of the samples were observed via field emission scanning electron microscopy (SEM, Hitachi S-4800) and high-resolution transmission electron microscopy (HRTEM, Tecnai G2 F30). X-ray diffraction (XRD) patterns in the Bragg’s angle (2θ) range of 10°–90° were recorded using a Bruker D8 diffractometer with Cu K_α radiation (λ = 0.1541 nm). X-ray photoelectron spectroscopy (XPS) was conducted using an ESCALAB 250 photoelectron spectrometer (Thermo Fisher Scientific, USA).

Figure 1a,b show the schematic and picture of the transparent and flexible TFTs, respectively. First of all, a 90-nm-thick AZO (Al₂O₃:ZnO = 2:98 wt%) gate electrode is deposited on PEN by radio frequency (RF) magnetron sputtering with the optimum condition (Power: 80 W, Pressure: 1 mTorr, Atmosphere: pure Ar). Then 320-nm-thick Al₂O₃ is fabricated by RF magnetron sputtering, acting as a gate insulator layer. Next, a bi-layer of 8-nm-thick IGZO and 3-nm-thick ultrathin Al₂O₃ serve as a channel layer. Finally, a 70-nm-thick AZO (Al₂O₃:ZnO = 2:98 wt%) film as S/D electrode is prepared by PLD at the optimized condition (O₂ flow rate: 0 sccm, pulsing energy: 450 mJ, repeating rate: 5 Hz). The films mentioned above are all patterned by shadow masks and deposited at room temperature, the entire preparation process does not require annealing.
The interface structure, cross-sectional morphology, and composition distribution of TFTs were measured by transmission electron microscopy (TEM, JEOL JEM-2100F). The surface band structure was measured by the X-ray photoelectron emission spectroscopy using Thermo VG ESCALAB 250 photoelectron spectrometer. The electrical characterizations of TFTs were measured by the semiconductor parameter analyzer (Agilent, 4155C). The optical properties of TFTs were measured by an ultraviolet-visible spectrophotometer (shimazu uv-2600).

X-ray diffraction (XRD) patterns were recorded on a Bruker D8 diffractometer in the 2θ range from 10 to 80° using Cu Kα radiation (λ = 1.5406 Å). Nitrogen adsorption-desorption isotherms were measured at 77 K on a Micromeritics Tristar 2420 analyzer (USA). Before measurements, the samples were degassed in vacuum at 190 °C for 10 h. The Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH) methods were used to calculate the specific surface area, pore volume, and pore size distribution, respectively. Field-emission scanning electron microscopy (FE-SEM) images were taken on a ZEISS Merlin Compact SEM equipped with energy-dispersive X-ray spectroscopy (INCAPentalFETx3 Oxford EDS). Sub-ångström-resolution high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) characterization was performed on a JEOL JEMARM200F STEM/TEM with a guaranteed resolution of 0.08 nm. Chemical states and composition of the samples were analyzed by X-ray photoelectron spectroscopy (XPS) on an ESCALAB 250 photoelectron spectrometer (Thermo Fisher Scientific) using a monochromatic Al Kα X-ray beam (1486.6 eV). All binding energies were referenced to the C 1s peak (284.6 eV). Inductively coupled plasma atomic emission spectroscopy (ICP-AES) measurements were conducted on Atomscan Advantage, Thermo Jarrell Ash, USA.

The humidity sensing materials were characterized by several techniques. The morphology was characterized by transmission electron microscope (TEM) (Sirion-200, Japan). The surface properties were examined by FT-IR (Thermo Scientific Nicolet iN10, USA), Raman-scattering spectroscopy (HORIBA Jobin Yvon Raman microscope (LabRAM HR800) and X-ray photoelectron spectra (XPS; ESCALAB 250 photoelectron spectrometer (ThermoFisher Scientific, USA).

Powder X-ray diffraction patterns (XRD) was performed using a Bruker D8 Advance X-ray diffractometer equipped with a Cu Kα radiation source (λ = 1.5418 Å) and operated at a scan rate of 6° min⁻¹. Scanning electron microscopy (SEM) was operated on FEI Nova NanoSEM 450 field emission scanning electron microscope. Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray (EDX) analysis were measured on a JEM-2100F microscope with an acceleration voltage of 200 kV. Temperature programmed desorption (TPD) was carried out on a Micromeritics Autochem II chemisorption analyzer with ethylbenzene probe molecules at 110 °C. Nitrogen adsorption-desorption isotherms were acquired on Quantachrome NOVA-2200e at 77 K. Prior to the measurement, the samples were degassed at 200 °C for 12 h with a gas flow of nitrogen. X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) experiments were recorded at a Kratos Axis Ultra DLD spectrometer and ESCALAB 250 photoelectron spectrometer (Thermo Fisher Scientific), respectively. The inductively coupled plasma atomic emission spectroscopy (ICP-AES) measurement was conducted on an iCAP6300 spectrometer for tungsten element analysis.