Effects of silicon doping on the performance of tin oxide thin film transistors

Abstract

Thin film transistors (TFTs) with silicon‐doped tin oxide (TSO) as channel layer were prepared by radio frequency magnetron sputtering. The decreased defect‐state‐related peak in photoluminescence (PL) excitation spectra and oxygen‐vacancy‐related O 1s peak in X‐ray photoelectron spectroscopy (XPS) with increasing Si content, accompanied by the decreased off‐state current and positive shift of turn‐on voltage, confirms that silicon can be a good carrier suppressor. The optimum TFT performance after annealing at 300 °C was achieved at Si content 5.4 at.%, with saturation mobility of 5.3 cm2 V−1 s−1, turn‐on voltage of −0.2 V, and on‐off current ratio of 3.3 × 106, respectively. Increasing the annealing temperature is useful to improve the mobility, but the polycrystalline structure formed above 350 °C goes against the uniformity of oxide TFTs.

Effect of deep UV laser treatment on silicon‐doped Tin oxide thin film

“…[21][22][23] The V O area proportion (V O /(V O +V M-O )) represents the relative quantity of oxygen vacancy. 24 As shown in Figure 6, the oxygen vacancy of a-STO is significantly increased after UV laser treatment. And with the increasing energy densities of UV laser treatment, the oxygen vacancy is increased.…”

“…The medium binding energy peaks (531.83‐532.65eV) represent oxygen vacancies (V O ), and the high binding energy peaks (532.40‐533.15eV) represent chemically adsorbed oxygen (V M‐OR ) . The V O area proportion (V O /(V O +V M‐O )) represents the relative quantity of oxygen vacancy . As shown in Figure , the oxygen vacancy of a‐STO is significantly increased after UV laser treatment.…”

High‐Performance Thin‐Film Transistors with Nickel‐Doped Indium Zinc Oxide Channel Layers

“…For all a‐IZNO thin films, the average transmittance (T average ) values in the visible light region (400–700 nm) were greater than 80%, indicating that these films are potential TFT channel materials for transparent displays. The optical bandgap ( E g ) of the a‐IZNO thin films was determined from the Tauc equationwhere α is the absorption coefficient, hν is the photon energy, and A is a material‐dependent constant. The fitting results are shown in the inset of Figure .…”

“…For all a-IZNO thin films, the average transmittance (T average ) values in the visible light region (400-700 nm) were greater than 80%, indicating that these films are potential TFT channel materials for transparent displays. The optical bandgap (E g ) of the a-IZNO thin films was determined from the Tauc equation [17] αhν…”

Effects of Mechanical Stress on Flexible Dual‐Gate a‐InGaZnO Thin‐Film Transistors

“…It can be seen that under SMS, the subthreshold swing (S.S.) value slightly increases from 0.13 to 0.16 V/decade. The S.S. value can be obtained by the formula S.S. ¼ (d(logI D )/dV G ) À1 [14,15] and is believed to be related to deep defects [16] in IGZO and at the IGZO/GI interface. As the gate voltage sweeps from À15 to 15 V, the carriers will fill the deep defects first, which affects the S.S. value, and then the shallow defects.…”