Memristors are nonlinear dynamic devices with applications in memory and neuromorphic computing. As memristors scale down to sub-2 nanometer thickness, atomic design is crucial for controlling switching dynamics. Here, we show the design of sub-2 nanometer MgO/Ga2O3/Al2O3 memristors with a bilayer structure consisting of a switching layer and an oxygen vacancy layer using in vacuo atomic layer deposition to control the number and sequence of atomic layers. A switching layer of intrinsic aluminum oxide provides the best switching speed, increasing by up to two orders of magnitude as the number of layers decreases from 12 to 5. Introducing oxygen vacancies in the switching layer offers little benefit and reduces on/off ratio and yield. The oxygen vacancy layer of 5–7 atomic layers strongly influences switching dynamics, with an interposed magnesium oxide/gallium oxide structure enabling switching faster than 50 nanoseconds. These results show that atomic layer design critically controls memristor switching dynamics. Memristors hold promise for memory and neuromorphic computing, but scaling them down to sub-2 nanometer thickness requires precise atomic design to optimize switching dynamics. Here, the authors demonstrate that a bilayer structure with a magnesium oxide/gallium oxide oxygen vacancy layer and intrinsic aluminum oxide switching layer significantly enhances switching speed, highlighting the importance of atomic layer control.
Marshall et al. (Fri,) studied this question.