This is a scalable ferroelectric non-volatile memory
Researchers from the University of Pennsylvania published a scientific article in Nature describing memory chips operating at temperatures of 600°C.
This is not an ordinary flash memory, but a scalable ferroelectric non-volatile memory, that is, based on ferrodiodes — ferroelectric diodes.
The ferrodiode memory uses a thin layer of synthesized piezoelectric aluminum scandium nitride (AIScN) with a thickness of 45 nm. It has the ability to retain electrical states after removal of an external electric field. Ferrodiode memory has been tested at 600 degrees for over 60 hours at less than 15V.
The authors of the work say that such memory can be useful in many areas, from space missions to deep drilling. But since this is only scientific work, it is difficult to say anything about the commercialization of this technology.