Phase change memory (PCM)



pcmPCMs data is encoded using the material’s phases: amorphous and crystalline. Those display strong resistivity contrast along with fast and reversible switching between those two states. In conventional devices the switching between the crystalline and amorphous states is accomplished via application of a short, high-energy electrical pulse which melts the PCM followed by a rapid thermal quench, locking-in the amorphous phase (RESET operation). The crystalline phase is formed via a longer, lower-energy electrical pulse, which crystallizes the material (SET operation). In order to read a bit, current is passed into the cell determining the high (RESET) or low resistance (SET) state. Excellent scaling characteristics, very high cyclability, and significantly fast read and write speeds own to PCM. These advantages spawn from the encoding of the information state using structure rather than charge, thus, in principle, PCM has no intrinsic lifetime limit. At the same time, fast and non-volatile switching may allow PCM also to move up the memory chain towards the core of the processor. Read more... 

Material development

We realize PCM heterostructures:
  • Planar (thin films)
  • Nanoscaled (core-shell NWs)
We use four different deposition techniques:


Device development

We develop several vehicles suitable for electrical testing to allow for the evaluation of different stacks of multilayers.
Physical characterization and modelling

We perform characterization and modelling to optimize the materials and device development. Such activities focus on structural, electronic, electrical and thermal properties.

We realize a demonstrator able to prove the concept of processing/storage multilayer device.