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Indium-tin-oxide (ITO) possesses high carrier mobility and a wide bandgap, which is a promising candidate for fabricating high-voltage (HV) thin-film transistors (TFTs) with a low on-resistance. No reports exist on HV ITO TFTs due to the limitation of the traditional TFT structure. This letter presents HV ITO TFTs featuring a drift region situated between the gate and drain. A 6-nm thick ITO channel is used, with the drift region spanning from $4~\mu $ m to $20~\mu $ m, encapsulated by an ITO layer ranging in thickness from 0 nm to 20 nm. Finally, an HV ITO TFT with a breakdown voltage (V $_{\text {BD}}\text {)}$ of 448 V and a low specific on-resistance (R $_{\text {on, {sp}}}\text {)}$ of 147 m $\Omega \cdot $ cm2 is realized. The trade-off relationship between VBD and R $_{\text {on, {sp}}}$ of proposed HV ITO TFTs approaches the theoretical limit of the single-RESURF lateral double-diffused MOSFET (LDMOS).

This study presents the high-voltage (HV) amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) with an offset region modulated by the indium–tin oxide (ITO) capping layer (ICL) near the drain side. The breakdown voltage (BV) is elevated because the offset region lowers the electric field between the gate and the drain. For the device without an ICL, a BV of 465 V and a large ON-resistance ( ${R} _{\text {on}}$ ) of 1000 $\text{M}\Omega $ are obtained at the offset region length ( ${L} _{\text {offset}}$ ) of $5 ~\mu \text{m}$ . The ICL effectively improves the ON-state characteristics of the HV device by reducing the resistance of the offset region. The output current of the TFTs increases with increasing ICL thickness ( ${T} _{\text {ICL}}$ ) due to the elevated electron density in the ITO film. The a-IGZO TFT achieves a BV of 326 V and a low ${R} _{\text {on}}$ of 207 $\text{k}\Omega $ with an offset region length ( ${L} _{\text {offset}}$ ) of $5 ~\mu \text{m}$ and a ${T} _{\text {ICL}}$ of 11.4 nm. The gate dielectric near the gate corner is found to be a breakdown weak point due to the electric field crowding, as confirmed by the TCAD simulations.

In this letter, a low dropout regulator (LDO) circuit based on an amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) is demonstrated for the first time. The LDO is realized through integrated enhancement- and depletion-mode (D-mode) TFTs, which are manufactured by local NH3 plasma treatment. Two-stage D-mode TFTs and a positive feedback technique are adopted in the error amplifier to enhance the output resistance and voltage gain. The LDO achieves a 1.79 V output across 2.3 V to 7 V supply voltage, with a low dropout voltage of 0.53 V and line regulation of 0.23%/V. It generated a quiescent current of $0.94~\mu \text{A}$ at a supply voltage of 5 V, and the low power consumption of only $4.7~\mu \text{W}$ is adopted. A maximum load current of $176~\mu \text{A}$ and a load regulation of 0.19 mV/ $\mu \text{A}$ is obtained. It owns a power supply rejection ratio (PSRR) of up to 43 dB at low frequencies.

In this article, amorphous indium–gallium–zinc oxide (a-IGZO) inverter integrated with enhancement-mode (E-mode) and depletion-mode (D-mode) thin-film transistors (TFTs) with the record high voltage gain of 372 V/V is demonstrated. The D-mode a-IGZO TFTs are realized by local hydrogen plasma treatment, which induces hydrogen doping in the a-IGZO film. The X-ray photoelectron spectroscopy (XPS) measurements prove that the hydrogen doping process increases the oxygen vacancies and free electron concentration in the a-IGZO. Therefore, the doped-hydrogen causes a negative shift in threshold voltage ( ${V} _{\text {th}}$ ) and improves the field effect mobility ( $\mu _{\text {FE}}$ ). After carefully optimizing the process of hydrogen plasma treatment, the inverter with a D-mode load is fabricated. The proposed inverter shows excellent performance, including a wide output swing range of almost 100%, a narrow transition region of 0.05 V, and a remarkable voltage gain of 372 V/V.

This work implemented bilateral 60-V amorphous In-Ga-Zn-O (a-IGZO) thin-film transistors (TFTs) with symmetric stair gate dielectric at the contact sides. The stair gate dielectric lowers the electrical field between the gate and the contacts, enhancing the breakdown voltage ( ${V}_{\text {BD}}$ ). The ${V}_{\text {BD}}$ was improved from sub-20 to 60 V and a bilateral ${V}_{\text {BD}}$ of 60 V was achieved at the total stair length ( ${L}_{\text {stair}}$ ) of over $2.9~\mu \text{m}$ for the proposed device. The transconductance ( ${G}_{m}$ ) degrades with the increasing ${L}_{\text {stair}}$ , attributed to the rising equivalent thickness of the stair gate dielectric. The gate-four-probe (GFP) method measurements reveal that the ON-resistance ( ${R}_{ \mathrm{\scriptscriptstyle ON}}$ ) of the stair gate region has a linear dependence on the ${L}_{\text {stair}}$ . The increasing electron concentration in the channel outside the stair region optimizes the output current, as confirmed by the TCAD simulation. The breakdown properties of the devices with a small $L_{\text {stair}}$ ( $ < 0.1~\mu \text{m}$ ) were also simulated. The proposed symmetric stair gate dielectric a-IGZO TFTs possessed low ${R}_{ \mathrm{\scriptscriptstyle ON}}$ and high ${V}_{\text {BD}}$ at the same time.

Due to the intrinsic weak immunogenicity of tumor cells and the quantitatively and functionally different populations of immune cells, immunosuppression has become the major obstacle for cancer immunotherapy. In this study, the biocompatible alginate was chemically modified with the carboxyethyl linker to facilitate the esterification reaction of the resultant carboxymethylated alginate (CMA) and resiquimod (R848), the agonist of Toll-like receptor 7/8 (TLR7/8a). In aqueous solution, the hydrophilic CMA and the hydrophobic R848 formed stable nanomicelles (CMA-R848) by self-assembling. After combined administration of CMA-R848 and cisplatin (Cis) in a gastric cancer (GC) model, the long-circulating CMA-R848 micelle reached the mild acidic tumor microenvironment (TME); the ester bonds were quickly cleaved by the ubiquitous esterase and released the single molecule of R848. In vitroand in vivoresults demonstrated that the released R848 efficiently promoted co-stimulatory molecules’ expression of dendritic cells (DCs), enhanced the antigen uptake and cross-presentation, and primed the cytotoxic T lymphocytes’ (CTLs) infiltration and killing effects, thereby reprogramming the “cold tumor” into the “hot tumor”. In addition, the ex vivotumor sections revealed that the released R848 effectively repolarized the M2-like tumor-associated macrophages (TAMs) into M1-like macrophages, exerted synergistic antitumor activity, reduced the tumor burden, and prolonged the overall survival duration of the GC animal model. Our study provided a targeting therapeutic strategy overcoming the limitations of R848 in vivo, and enhanced the efficacy of GC chemotherapy and immunotherapy by TME modulation.

2D materials provide an alternative way to passivate the Ge/oxide interface because of their conduction and valence band offsets. The effectiveness of their interface passivation is examined by evaluating the carriers' population in the channel of 2D passivated Ge n- and p-metal-oxide-semiconductor field-effect transistor (MOSFETs). The bilayer MoS2interfacial passivation layer reduces both surface roughness and phonon scattering, which provides a performance boost. Monolayer MoSe2, WS2, MoS2, and black phosphorus, as well as bilayer MoS2and WS2, can realize effective interface passivation for both Ge n- and p-MOSFETs. The carriers can penetrate 2D material if there are more than two 2D layers.