1) To investigate electro-thermal phenomena that take place in nanometer scale phase change memory devices through experimental and computational studies. 2) To computationally and experimentally investigate aggressively scaled phase-change memory cell designs including access devices and compact composite cell approaches. 3) To support graduate and undergraduate education, as well as outreach activities, in electronic devices, electro-thermal effects, nanoscience and nanotechnology.
Intellectual Merit: Phase change memory is a non-volatile resistive memory technology that has shown potential for scalability down to < 10 nm range with fast access times, high packing density and low energy consumption. Phase change memory makes use of a class of materials that can be reversibly changed between low-resistance crystalline and high-resistance amorphous states through rapid melting or annealing. Integration of phase change memory with silicon electronics for high-density storage and high-performance low-power storage requires an integrated approach bridging across physics, materials science, device engineering and circuit design. The proposed work is an integrated research program in collaboration with IBM, utilizing finite element simulations and experiments on phase change memory materials, test structures and devices to close the gaps of knowledge across these fields to make phase change memory a main stream memory technology. Finite element simulations will be used to understand the contribution of electro-thermal phenomena, design of experiments and design of phase change memory cells. The experiments will be used to extract important physical parameters and demonstrate proof of principle. Experiments integrated with computational studies will be used to extract important physical parameters that cannot be measured directly, probe electro-thermal processes that are not very well understood and design novel cell structures. Phase-change elements with access devices will be studied as a whole, and potential composite devices where the access device is an integral part of the phase-change element will be investigated for their potential for high-density arrays. The fabrication processes will be performed at IBM Watson Research Center using state-of-the-art tools through an existing collaborative arrangement. Materials and device characterization, and experimental and computational studies will be carried out at University of Connecticut.
Broader impacts: The findings from this project will provide for better understanding of all devices that either utilize or are affected by electro-thermal effects such as other resistive memory technologies, micro thermoelectric generators and nanoscale transistors. The results will be published in scientific journals and online (e.g. nanoHub, thermalHub). Graduate and undergraduate students will have access to the facilities and expertise at IBM Watson Research Center, will get experience on nanofabrication, nanoelectronic device design and characterization, and will learn about phase changes, thermoelectric transport, instrumentation and numerical modeling. Findings will be used for outreach activities and the research effort will be integrated with undergraduate and graduate level courses at University of Connecticut.
