Current-limiting electrodes

摘要

A resistive-switching memory (ReRAM cell) has a current-limiting electrode layer that combines the functions of an embedded resistor, an outer electrode, and an intermediate electrode, reducing the thickness of the ReRAM stack and simplifying the fabrication process. The materials include compound nitrides of a transition metal and one of aluminum, boron, or silicon. In experiments with tantalum silicon nitride, peak yield in the desired resistivity range corresponded to ˜24 at % silicon and ˜32 at % nitrogen, believed to optimize the trade-off between inhibiting TaSi2 formation and minimizing nitrogen diffusion. A binary metal nitride may be formed at one or more of the interfaces between the current-limiting electrode and neighboring layers such as metal-oxide switching layers.

主权项

1. A device comprising:
a first layer formed over a substrate,
wherein the first layer is operable as a first electrode; a second layer formed over the first layer,
wherein the second layer is operable to reversibly change resistance between at least two stable states responsive to a write signal; a third layer formed over the second layer,
wherein the third layer is operable as a second electrode;wherein the first layer or the third layer is a constant-resistance layer operable as a current-limiting electrode;wherein the constant-resistance layer comprises a first portion and a second portion,wherein the first portion comprises a compound nitride of a transition metal and an additional element;wherein the second portion comprises a binary nitride;wherein the second portion directly interfaces the second layer; andwherein the additional element comprises at least one of aluminum, boron, or silicon.