The single event effect in ferroelectric-gate field-effect transistor(FeFET) under heavy ion irradiation is investigated in this paper. The simulation results show that the transient responses are much lower in a FeFET than in a conventional metal–oxide–semiconductor field-effect transistor(MOSFET) when the ion strikes the channel. The main reason is that the polarization-induced charges(the polarization direction here is away from the silicon surface) bring a negative surface potential which will affect the distribution of carriers and charge collection in different electrodes significantly. The simulation results are expected to explain that the FeFET has a relatively good immunity to single event effect.
The electronic structures and magnetic properties of(Mn, N)-codoped Zn O are investigated by using the firstprinciples calculations. In the ferromagnetic state, as N substitutes for the intermediate O atom of the nearest neighboring Mn ions, about 0.5 electron per Mn2+ion transfers to the N2-ion, which leads to the high-state Mn ions(close to +2.5)and trivalent N3-ions. In an antiferromagnetic state, one electron transfers to the N2-ion from the downspin Mn2+ion,while no electron transfer occurs for the upspin Mn2+ion. The(Mn, N)-codoped Zn O system shows ferromagnetism,which is attributed to the hybridization between Mn 3d and N 2p orbitals.
The alternation from bipolar to unipolar resistive switching is observed in perovskite La0.01Sr0.99TiO3thin films.These two switching modes can be activated separately depending on the compliance current(Icomp)during the electroforming process:with a higher Icomp(5 mA)the unipolar resistance switching behavior is measured,while the bipolar resistance switching behavior is observed with a lower Icomp(1 mA).On the basis of I–V characteristics,the switching mechanisms for the URS and BRS modes are considered as being a change in the Schottky-like barrier height and/or width at the Pt/La-SrTiO3interface and the formation and disruption of conduction filaments,respectively.
