Power Saving for Computer Memories by Use of Aluminum
—Clarification of operation mechanism of new nonvolatile memory using aluminum-oxide film—

“DRAM,” the main memory widely used now for computers throughout the world, has the problem of consuming a great deal of power because of its volatility. Therefore, “ReRAM (resistive random access memory)” using transition metal is intensively being researched as a next-generation nonvolatile memory that can overcome this problem. However, ReRAMs are not really durable because chemical changes in its operation generate byproducts.

In this study, we performed a synchrotron radiation experiment on amorphous aluminum-oxide film in order to elucidate the mechanism of operation of a new nonvolatile memory .

It was directly observed that the electronic state of the oxygen site changed with the ON-OFF switching of the memory. On the other hand, the electronic state of the aluminum site didn’t change, which revealed that no chemical change occurred.

ReRAM that uses amorphous aluminum-oxide film doesn’t degrade through chemical changes, so it is expected that it can solve the electricity consumption problem involved in existing DRAM, while achieving an improved durability equivalent to that of DRAM. Furthermore, new materials for electronic devices are expected to be developed based on the principle of charge of electrons into oxygen vacancies and their discharge.