Recovery curve for threshold-switching NbO2

Abstract

Threshold switching has been observed and studied in thin films of NbOx (x?2) in the sandwich configuration and in a single-crystal device having both a gap and sandwich configuration. The recovery curve has been determined by measuring the reswitching voltage after a specific zero-voltage interruption time. Data indicate a maximum allowable interruption time of about 200 ns without a switch-off transition. This is interpreted as the distribution trapped-carrier lifetime for polycrystalline NbO2.

Switching effect and the metal–insulator transition in electric field

“…In high electric fields electronic effects influence the MIT so that a field-induced increase in the charge carrier concentration (due to either injection from contacts or impact ionization, or due to fieldstimulated donor ionization-i.e. the Poole-Frenkel effect) leads to the elimination of the Mott-Hubbard energy gap at ToT t [22,28]. This effect may be treated also as a lowering of T t due to an excess negative charge (electrons), and the dependence of V th on T deviates from the behaviour described by the critical temperature model.…”

“…In the present work, this model has been developed for a particular case (VO 2 ), but it is also applicable to other materials (such as, e.g., NbO 2 , which exhibits the MIT at T t ¼1070 K [8,13,28,29]), and even to the materials exhibiting only the nonequilibrium MIT, for example, to amorphous semiconductors (including chalcogenide glass semiconductors, CGS) [19,30]. Moreover, the model can describe the switching effect with N-type NDR, not only that with S-type NDR.…”

“…In some cases, the MIT may be unobservable under the temperature change in equilibrium conditions, but it displays itself only under the applied electric field. It is quite likely that such a situation just takes place in CGS; similar effects obviously occur also in some MOM structures based on transition metal oxides [22,[28][29][30][32][33][34][35].…”

Electroforming and Switching in Oxides of Transition Metals: The Role of Metal–Insulator Transition in the Switching Mechanism

“…Threshold switching (without any memory efup from 22 g of benzoic acid (C 6 H 5 COOH) plus 40 ml of fects) with an S-type V-I curve has been observed in the saturated aqueous solution of Na 2 B 4 O 7 per liter of metal-oxide-metal (MOM) structures with Nb 2 O 5 (2,3), acetone (10). Fe, Ti, and several Nb samples were anodized NbO 2 (4,5), TiO 2 (3,6), VO 2 (7), Ta 2 O 5 (3), and Fe oxide in a KNO 3 ϩ NaNO 3 eutectic melt at 570-620 K. The (8). The oxide films were prepared by different methods:…”

Динамика Развития Канала Переключения В Планарных Структурах На Основе Диоксида Ванадия

“…При том, что длительность перехода из высокоомного в низкоомное состояние определялась в ряде работ [5][6][7][8][9][10][11], практи-чески отсутствуют данные о длительности обратного перехода диоксида ванадия: из низкоомного в высокоом-ное состояние после прохождения импульса напряжения. Единственным исключением является, по-видимому, ра-бота [16], в которой представлены результаты иссле-дования эффекта ЭП в структурах на основе NbO 2 , где переключение связано с ФПМП, имеющем место в диоксиде ниобия при значительно более высокой по сравнению с VO 2 температуре (1070 K) [17].…”