RRAM
RRAM – Resistive Random-Access Memory
RRAM (Resistive Random-Access Memory), also known as ReRAM, is a type of non-volatile memory that stores data by changing the resistance of a dielectric material (usually an oxide) when a voltage is applied. It is recognized as one of the most promising candidates for next-generation memory due to its simple structure, high speed, low power consumption, and scalability beyond the limits of conventional flash memory.
Structure:
A typical RRAM cell consists of:
Metal–Insulator–Metal (MIM) structure:
- Top Electrode (TE)
- Resistive Switching Layer (often oxides like HfOx, TiOx, TaOx, etc.)
- Bottom Electrode (BE)
Variants may include:
- Filamentary-type RRAM (conductive filaments form and rupture)
- Interface-type RRAM (resistance changes at the interface)
Working Principle:
RRAM operates by reversibly switching between a High Resistance State (HRS) and a Low Resistance State (LRS):
- SET Process: A positive voltage creates or enhances a conductive filament (typically composed of oxygen vacancies or metal ions) through the dielectric → switches to LRS (logic “1”)
- RESET Process: A reverse voltage ruptures the filament or redistributes the defects → returns to HRS (logic “0”)
This resistance change is non-volatile, meaning it is retained even after power is removed.
Key Features & Advantages:
- Fast switching speed (<10 ns)
- Low operating voltage (~1V or less)
- Excellent scalability to sub-10nm nodes
- High endurance (10⁶–10⁹ cycles) and retention (>10 years)
- 3D integration friendly for high-density memory stacks
- Simple MIM structure enables easy integration with CMOS back-end
RRAM Device Types:
- Unipolar RRAM: SET and RESET at same polarity but different voltages
- Bipolar RRAM: SET and RESET with opposite voltage polarities
- Analog RRAM: Continuous resistance modulation for neuromorphic computing
Applications:
- Non-volatile memory (stand-alone or embedded)
- Storage-class memory (SCM) bridging DRAM and NAND
- Neuromorphic computing and artificial intelligence accelerators
- Hardware security and physically unclonable functions (PUFs)
- Low-power IoT and edge devices
Our RRAM Technology Services:
We support the complete RRAM development lifecycle, offering:
- TCAD simulation of resistive switching physics (filament formation, ion migration, trap-assisted tunneling)
- Custom RRAM cell and array design
- Material selection and device modeling (HfOx, TiOx, TaOx, etc.)
- Integration with CMOS back-end flows
- RRAM layout design and PDK compatibility
- Fabrication support including deposition (ALD, sputtering), etch, and electrical characterization