Post-Moore Memory Technology: Sneak Path Current (SPC) Phenomena on RRAM Crossbar Array and Solutions.

Area of Science:

• Materials Science
• Electrical Engineering
• Computer Engineering

Background:

• Sneak path current (SPC) is a significant challenge in high-density crossbar memory arrays, leading to reduced read accuracy and crosstalk.
• Existing crossbar architectures are susceptible to SPC, hindering the development of advanced storage solutions.

Purpose of the Study:

• To investigate the impact of sneak path currents on crossbar memory arrays.
• To evaluate the effectiveness of a bilayer stacked structure in mitigating SPC and improving read margin.
• To analyze voltage stress-induced read margin degradation in bilayer structures.

Main Methods:

• Electrical experimental measurements were conducted on a crossbar array using a half-read scheme.
• A bilayer stacked structure was implemented to assess its impact on SPC and read margin.
• Voltage-read stress tests were performed to evaluate read margin degradation.

Main Results:

• The bilayer stacked structure improved the read margin of the selected cell.
• A reduction of approximately 20% in sneak path current was observed with the bilayer structure.
• The bilayer structure exhibited less voltage stress-induced read margin degradation due to its intrinsic nonlinearity.

Conclusions:

• The oxide-based bilayer stacked resistive random access memory (RRAM) offers immunity to sneak path currents.
• This bilayer RRAM is a promising solution for high-density memory integrations and in-memory computing applications.
• The study demonstrates a viable approach to enhance the reliability of future high-density storage systems.