The programmable metallization cell, or PMC, is a non-volatile computer memory developed at Arizona State University.
PMC is an electrochemical metallization memory that relies on redox reactions to form and dissolve a conductive filament.
[3] The resistance state of a PMC is controlled by the formation (programming) or dissolution (erasing) of a metallic conductive filament between the two terminals of the cell.
PMC rely on the formation of a metallic conductive filament to transition to a low resistance state (LRS).
A PMC can be "erased" into a high resistance state (HRS) by applying a negative voltage bias to the anode.
With the filament removed, the PMC is analogous to parallel plate capacitor with a high resistance of several MΩ to GΩ between the contacts.
CBRAM differs from metal-oxide ReRAM in that for CBRAM metal ions dissolve readily in the material between the two electrodes, while for metal-oxides, the material between the electrodes requires a high electric field causing local damage akin to dielectric breakdown, producing a trail of conducting defects (sometimes called a "filament").
Hence for CBRAM, one electrode must provide the dissolving ions, while for metal-oxide RRAM, a one-time "forming" step is required to generate the local damage.
As flash scales rapidly downward in size the charge leakage increasingly becomes a problem, which led to predictions of its demise.
However, massive market investment drove development of flash at rates in excess of Moore's Law, and semiconductor fabrication plants using 30 nm processes were brought online in late 2007.
[6] PMC, in theory, can scale to sizes much smaller than flash, theoretically as small as a few ion widths wide.
[6] PMC technology was developed by Michael Kozicki, professor of electrical engineering at Arizona State University in the 1990s.
[6] infineon had spun off memory business to its Qimonda company, which in turn sold it to Adesto Technologies.