Topics Include 3D Sequential Integration and Use of Phase Change Memory As Synapse for Ultra-Dense Neuromorphic Systems

GRENOBLE, France – Oct. 26, 2011 – CEA-Leti researchers will present seven papers at the 2011 International Electron Devices Meeting, Dec. 5-7, in Washington, D.C., including papers on 3D sequential integration and phase change memory (PCM) as synapse for ultra-dense neuromorphic systems.

A paper by Perrine Batude and others on “Advances, Challenges and Opportunities in 3D CMOS Sequential Integration” explores the possibility of using the third- dimension potential fully by, for example, connecting two stacked layers at the transistor scale. The paper contrasts that with 3D parallel integration, which is limited to connecting blocks of a few thousand transistors.

This ability to offer fine-grain circuit partitioning at the transistor scale can be useful for a wide range of applications such as FPGAs, highly miniaturized imagers and CMOS gates. The repartitioning of the different functions on distinct levels offers the possibility to optimize each technology separately, while vertical proximity would enable delay reduction.

Addressing growing interest in the development of biologically inspired neuromorphic circuits offering low power, highly parallel, and fault-tolerant systems, Leti and partners sought to demonstrate that hybrid neuromorphic chips with memristive synapses can be designed for applications like real-time visual-pattern extraction.

A paper by Manan Suri and the CEA team titled “Phase Change Memory as Synapse for Ultra-Dense Neuromorphic Systems: Application to Complex Visual Pattern Extraction” demonstrates a unique energy-efficient methodology developed to use PCM devices as energy-efficient synapses in large-scale neuromorphic systems.

Using advanced electrical characterization, behavioral modeling and circuit-level simulations, the team demonstrated a spiking neural network with about 4 million synapses, capable of complex visual-pattern extraction.

About CEA-Leti

Leti is an institute of CEA, a French research-and-technology organization with activities in energy, IT, healthcare, defence and security. Leti is focused on creating value and innovation through technology transfer to its industrial partners. It specializes in nanotechnologies and their applications, from wireless devices and systems, to biology, healthcare and photonics. NEMS and MEMS are at the core of its activities. An anchor of the MINATEC campus, CEA-Leti operates 8,000-m² of state-of-the-art clean room space on 200mm and 300mm wafer platforms. It employs 1,400 scientists and engineers and hosts more than 190 Ph.D. students and 200 assignees from partner companies. CEA-Leti owns more than 1,700 patent families.

For more information, visit www.leti.fr.