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The 2021 release of Reimagining Our Futures Together: A New Social Contract for Education by the United Nations Educational, Scientific, and Cultural Organization was a reaction to a number of serious problems discovered in worldwide educational reforms. It sought to establish a new social compact for education to fulfill its unmet promise in the face of many educational crises and to combat future uncertainty. Using the methods of 271 Education Group as a case study, this article examines China's efforts to transform basic education in response to widespread educational issues and how they have represented the major principles espoused by the UNESCO report. The article elaborates on the coping strategies of 271 Education Group, such as incorporating eco-civilization education into basic schooling, constructing life-based curricula that are built on knowledge commons, introducing pedagogy rooted in cooperation and solidarity, and promoting teacher professional development through collaborative educational research.

β-Ga2O3 has been subjected to intense research interest as an ultrawide bandgap semiconductor. The epitaxial growth technique of β-Ga2O3 thin films plays a fundamental and vital role in Ga2O3-based device fabrication. In this work, the epitaxial growth mechanisms of β-Ga2O3 on four low-Miller-index facets, (100), (010), (001), and ( 2 ¯ 01), are systematically explored using large-scale machine-learning molecular dynamics simulations at the atomic scale. The simulations reveal that the migration of the face-centered cubic stacking O sublattice plays a dominant role in the different growth mechanisms between the (100)/(010)/(001) and ( 2 ¯ 01) orientations. The resultant complex combinations of the stacking faults and twin boundaries are carefully identified and show good agreement with experimental observations and ab initio calculations. Our results provide useful insights into the gas-phase epitaxial growth of β-Ga2O3 thin films and suggest possible ways to tailor its properties for specific applications. [ABSTRACT FROM AUTHOR]

In this work, we focused on investigating the transport-limited trapping effects in GaN-on-Si buffer layers as well as impact of the thickness of buffer layers (TBuf) upon such effects. Vertical transport dynamics of charges within the buffer layers and their key energy levels are quantitatively and statistically investigated and analyzed. The results show that an increased TBuf diminishes both impurity conduction of the defect band formed by carbon doping as well as the injection of electrons from the substrate, greatly diminishing the current collapse and improving the stability of the device. Such enhancement is mainly attributed to the reduced vertical electric field within the thickened epitaxy, which provides an additional pathway to address the current collapse and yields more efficient power GaN-on-Si devices. [ABSTRACT FROM AUTHOR]

Ga2O3 is a wide-band gap semiconductor of emergent importance for applications in electronics and optoelectronics. However, vital information of the properties of complex coexisting Ga2O3 polymorphs and low-symmetry disordered structures is missing. We develop two types of machine-learning Gaussian approximation potentials (ML-GAPs) for Ga2O3 with high accuracy for β/κ/α/δ/γ polymorphs and generality for disordered stoichiometric structures. We release two versions of interatomic potentials in parallel, namely soapGAP and tabGAP, for high accuracy and exceeding speedup, respectively. Both potentials can reproduce the structural properties of all the five polymorphs in an exceptional agreement with ab initio results, meanwhile boost the computational efficiency with 5 × 102 and 2 × 105 computing speed increases compared to density functional theory, respectively. Moreover, the Ga2O3 liquid-solid phase transition proceeds in three different stages. This experimentally unrevealed complex dynamics can be understood in terms of distinctly different mobilities of O and Ga sublattices in the interfacial layer. [ABSTRACT FROM AUTHOR]

${p}$ -channel GaN field-effect transistors (FETs) with a SiNx/GaON gate stack have been demonstrated with enhanced stability within a wide range of voltage bias and temperature. In this letter, the gate leakage characteristics and reliability of this unconventional staggered gate stack are investigated. At relatively low gate voltages, the gate current is suppressed owing to the buried-channel structure and the presence of GaON that presents an effective hole barrier. With more negative gate biases, the gate leakage was found to be dominated by the transport of holes that spillover from the ${p}$ -channel through the SiNx via Poole-Frenkel emission. Based on this gate leakage mechanism at large gate bias, $\sqrt {{\mathrm {E}}} $ model was used for gate lifetime prediction. The maximum applicable ON-state gate voltage of −7.3 V is obtained for a 10-year lifetime with a 1% gate failure rate. [ABSTRACT FROM AUTHOR]

In this article, the impacts of the off-state gate bias (VGS,OFF) on dynamic on-resistance (RON) are systematically investigated in commercial Schottky-type p-GaN Gate high-electron-mobility transistors. Double-pulse tester and pulsed I–V system are adopted to evaluate the dynamic RON with various off-state gate and drain bias (VDS,OFF) under hard- and soft-switching conditions. More negative VGS,OFF can aggravate the dynamic RON degradation under both soft- and hard-switching, especially when switching with a high VDS,OFF. The impacts of VGS,OFF on switching transients and off-state stress are investigated separately to reveal the underlying mechanisms, which are found to be associated with the generation and movements of holes. The off-state gate bias of the voltage-driving scheme needs to be carefully considered according to the identified mechanisms in terms of dynamic on-resistance degradation. [ABSTRACT FROM AUTHOR]

Two-dimensional van der Waals heterostructures with strong intrinsic ferroelectrics are highly promising for novel devices with designed electronic properties. The polarization reversal transition of the 2D ferroelectric Ga 2 O 3 monolayer offers a new approach to tune the photocatalytic and electrical properties of MoS 2 /Ga 2 O 3 heterogeneous bilayers. In this work, we study MoS 2 /Ga 2 O 3 heterogeneous bilayers with different intrinsic polarization using hybrid-functional calculations. We closely investigate the structural, electronic and optical properties of two stable stacking configurations with opposite polarization. The results reveal a distinct switch from type-I to type-II heterostructures owing to polarization reversal transition of the 2D ferroelectric Ga 2 O 3 monolayer. Biaxial strain engineering leads to type-I-to-II and type-II-to-III transitions in the two polarized models, respectively. Intriguingly, one of the MoS 2 /Ga 2 O 3 heterolayers has a larger spatial separation of the valence and conduction band edges and excellent optical absorption ranging from infrared to ultraviolet region under biaxial strain, thus ensuring promising novel applications such as flexible electrical and optical devices. Based on the highly tunable physical properties of the bilayer heterostructures, we further explore their potential applications, such as photocatalytic water splitting and field-controlled switch channel in MOSFET devices.