With experimental and numerical simulation, we report the origin of the performance enhancement in p-type SnO thin-film transistors (TFTs) due to fluorine plasma treatment (FPT). To study the effect of fluorination, using the reactive-ion-etching process, the devices are treated at various plasma powers upto 60 W. It is observed, through X-ray photoelectron spectroscopy and XRD measurements, that the plasma fluorination modifies the defect/trap states of SnO channel and SnO/HfO ₂ interface. These effects are introduced through density of state (DOS) model for SnO in numerical simulations, to understand the routes of electrical performance improvement. It is observed that the attributes of donor-like band-tail state and acceptor-like Gaussian defect states (Sn vacancies) are modified in overall DOS due to plasma fluorination. The treated device shows excellent electrical performances with high ${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ ratio of ~10 ⁷ and low substhreshold swing of ~ 100 mV/dec and field-effect mobility ( $\mu _{\text {FE}}$ ) of 2.13 cm ² V ⁻¹ s ⁻¹ .

This letter reports on a tin oxide (SnO) thin-film transistor (TFT) with p-type conduction that uses aluminum (Al) doping in the SnO active channel layer. Performance enhancements were further achieved by applying fluorine plasma treatment on the p-type Al-doped SnO channel layer. The effects of the fluorine plasma treatment were also investigated.By tuning the power of the fluorine plasma treatment on the p-type Al-doped SnO channel layer, the optimal TFT device showed a very high on/off current ratio of 2.58×10⁶ and a low threshold swing of 174 mV/decade, which could be attributed to the passivation effect of the plasma fluorination on the dominant donor-like traps at the SnO/HfO₂ interface, as reflected by the suppression of the hysteresis phenomenon, the low density of interface traps, and the small subthreshold swing. The results indicate that the p-type Al-doped SnO TFT device with fluorine plasma treatment has considerable potential for application in future high-performance displays.

For the first time, we successfully demonstrated the dopant-free HfO ₂ negative capacitance (NC) transistor featuring a low gate-overdrive voltage and a nearly hysteresis-free sub-40 mV/dec swing. These excellent performances can be ascribed to the reduction of the monoclinic phase suppressed with the thickness scaling and gate stress engineering favorably rearranging oxygen vacancies to boost orthorhombic phase transition. The highly scalable and dopant-free NC transistor shows the potential for the application of advanced CMOS technology.

In this brief, we reported a ferroelectric versatile memory with strained-gate engineering. The versatile memory with high-strain-gate showed a >40% improvement on ferroelectric hysteresis window, compared to low-strain case. The high compressive stress induced from high nitrogen-content TaN enhances monoclinic-to-orthorhombic phase transition to reach stronger ferrolectric polarization and lower depolarization field. The versatile memory featuring ferroelectric negative capacitance exhibited excellent transfer characteristics of the sub-60-mVdec subthreshold swing, ultralow off-state leakage of <;1fA/μm and >10 ⁸ on/off current ratio. Furthermore, the ferroelectric versatile memory can be switched by ±5 V under 20-ns speed for a long endurance cycling (~10 ¹² cycles). The low-power operation can be ascribed to the amplification of the surface potential to reach the strong inversion and fast domain polarization at the correspondingly low program/erase voltages.