Memristive Devices

Business Unit »Process, Device and Packaging Technologies«

 Wafer-level memristors using memristive BiFeO3.
© Fraunhofer ENAS
Wafer-level memristors using memristive BiFeO3.
Memristors as arrays and as single devices for memory and in-memory computing applications.
© Fraunhofer ENAS
Fig. 1: Memristors as arrays and as single devices for memory and in-memory computing applications.
Electrical behavior of memristive devices, (left) BiFeO3-based technologies, (right) TiO2-based technologies.
© Fraunhofer ENAS
Fig. 2: Electrical behavior of memristive devices, (left) BiFeO3-based technologies, (right) TiO2-based technologies.

The topic "Memristive Devices" deals with the fabrication, integration and characterization of memristors for non-volatile memory applications. In the broadest sense, a memristor is an electrical resistor that changes non-volatile as a function of time and the applied voltage. A distinction is made between memristors with digital switching behavior, which can be switched between a high and low resistance state, and analog components, which change their internal resistance continuously with time (memristivity). By applying a voltage with reversed polarity, the memristor can be reset accordingly.

Due to their inherent biorealism, memristive devices are particularly well suited for technically reproducing components of the brain and nervous system. One of their main applications is therefore the construction of technical neural networks for the hardware-based realization of artificial intelligence. Other fields of application are high-density memories based on nanoionic redox processes, so-called ReRAMS, and zero-energy sensors in combination with charge-generating physical converters.

Fraunhofer ENAS has been working in the field of memristive devices for many years and has already transferred some of these devices into application, fig. 1 and 2. One of the focal points was the production of zero-energy sensors, which are realized by means of a combination of piezoelectric transducer and memristor, fig. 3. Thereby, the piezoelectric transducer provides sufficient energy to write the memristor when shocks and vibrations occur. By means of a special RFID-based wireless interface, the sensors are read out and reset. Another focus is neuromorphic computing using memristive synapses. Using our special, patented BiFeO3 technology, synaptic circuits with very low power dissipation, high performance and very good signal-to-noise ratio can be implemented. The memristors are available as single devices as well as memristive cross-bar arrays, Fig. 4. First investigations on the integration On Top on CMOS are already in progress.

Fig. 3: Zero-energy vibration sensors with memristive component as non-volatile memory (left) finished sensor system, (right) electrical behavior under the influence of vibrations.
Fig. 4: Cross-bar arrays with memristive BiFeO3 for neuromorphic circuits.

Our services:

  • Manufacturing of memristive devices based on our two established and partly patented technologies, BiFeO3 and TiO2, design as single device as well as cross-bar array with arbitrary cell number and density
  • Integration of memristive components into existing technology concepts, adaptation of material characteristics, layout and manufacturing technology
  • Special test strategies for memristive devices for fast and reliable characterization of memristors on wafer level as well as in high-density cross-bar structures
  • Zero-energy sensor technology with memristive memories for multiple application scenarios, e.g. for monitoring shocks, vibrations, temperature changes and light influences
  • Ready-made components for neuromorphic circuits including circuit design
  • Investigation of new material systems with memristive behavior for special applications

Are you interested in our memristive components and systems? Get in touch with us.