Mimcaps with quantum wells as selector elements for crossbar memory arrays

摘要

Selector devices suitable for memory arrays have low leakage currents at low voltages, reducing sneak current paths for non-selected devices, and high leakage currents at high voltages, reducing voltage drops during switching. The selector device may include a non-conductive tri-layer between two electrodes. The non-conductive tri-layer may include a low-bandgap dielectric layer between two higher-bandgap dielectric layers. The high-bandgap dielectric layers may be doped to form traps at energy levels higher than the write voltage of the memory device. With a thin low-bandgap layer and a large bandgap difference from the high-bandgap layers, the selector may operate as a quantum well, conductive when the electrode Fermi level matches the lowest energy level of the quantum well and insulating at lower voltages.

主权项

1. A selector, comprising:
a substrate; a first conductive layer over the substrate, wherein the first layer is operable as a first electrode; a first non-conductive layer over the first conductive layer; a second non-conductive layer over the first non-conductive layer; a third non-conductive layer over the second non-conductive layer; and a second conductive layer over the third non-conductive layer; wherein the first non-conductive layer, the second non-conductive layer, and the third non-conductive layer form a quantum well having a lowest energy level; wherein the first conductive layer has a first Fermi level and the second conductive layer has a second Fermi level; wherein the first Fermi level and the second Fermi level are less than the lowest energy level when less than a turn-on voltage is applied between the first conductive layer and the second conductive layer; and wherein one of the first Fermi level or the second Fermi level is equal to the first energy level when a turn-on voltage is applied between the first conductive layer and the second conductive layer.