Tokyo Electron Limited

The State University of New York

Karsten Beckmann

Nathaniel C Cady

Sergey Alexandrovich Voronin

Shyam Sridhar

Martin Rodgers

Qi Wang

A selector device includes a first electrode composed of a first metal having a first work function. A second electrode is composed of a second metal having a second work function. A selector layer is disposed between the first and second electrodes and is composed of a dielectric material having a conduction band and a valence band defining a band gap of at least 5 electron volts. Dopant atoms are disposed in the selector layer to form a sub-conduction band that is below the conduction band and above the work functions. When a threshold voltage is applied across the first and second electrodes, and a magnitude of the threshold voltage exceeds an energy difference between the sub-conduction band and the work functions, but does not exceed an energy difference between the conduction band and the work functions, an on-current will conduct through the selector layer.

Selector devices for a memory cell

The performance of a ReRAM structure may be stabilized by utilizing a dry chemical gas removal (or cleaning) process to remove sidewall residue and/or etch by-products after etching the ReRAM stack layers. The dry chemical gas removal process decreases undesirable changes in the ReRAM forming voltage that may result from such sidewall residue and/or etch by-products. Specifically, the dry chemical gas removal process may reduce the ReRAM forming voltage that may otherwise result in a ReRAM structure that has the sidewall residue and/or etch by-products. In one embodiment, the dry chemical gas removal process may comprise utilizing a combination of HF and NHgases. The dry chemical gas removal process utilizing HF and NHgases may be particularly suited for removing halogen containing sidewall residue and/or etch by-products.

Methods for resistive RAM (ReRAM) performance stabilization via dry etch clean treatment

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Albany, NY, United States of America

Karsten Beckmann