Ru/Si Diode for Cross-Point Memory Leakage Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In larger cross-point memory arrays, leakage through unselected or partially selected memory cells becomes problematic, affecting the reliability and efficiency of data storage.

Innovation Solution

The implementation of memory cells with a resistive element coupled in series with a diode, where the diodes contain ruthenium and silicon, including a ruthenium silicide interface, to enhance the control and isolation of current flow between conductive lines, thereby reducing leakage and improving memory cell selectivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If cross-point memory arrays are made larger to increase memory density, then memory capacity is improved, but leakage through unselected memory cells increases

Engineering Contradiction:
Improvememory capacityVSAvoidleakage current
Core Design Contradiction:
Quantity of substanceVSLoss of energy

Solution Approach 1:

The memory cell is segmented into distinct functional components: a resistive element for data storage and a diode for current control. This segmentation allows the diode to selectively control current flow to the resistive element, preventing leakage to unselected cells while maintaining high memory density in large arrays.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A diode is introduced as an intermediary component between the access lines and the resistive element. This diode acts as a mediator that controls current flow direction and magnitude, enabling selective access to memory cells and blocking leakage currents in unselected cells, thus resolving the contradiction between array size and leakage.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Device complexity

If conventional memory cell structures are used to maintain simplicity, then device complexity is reduced, but selectivity and leakage control deteriorate

Engineering Contradiction:
Improvememory cell structureVSAvoidcell selectivity
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The memory cell is divided into functionally distinct segments: a resistive element for data storage and a diode for current control. This segmentation provides clear separation of concerns, where the diode handles selectivity and the resistive element handles data storage, improving reliability without excessive complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The diode serves multiple functions within the memory cell structure: it provides current rectification, controls current flow to selected cells, and prevents leakage to unselected cells. This multi-functionality improves selectivity and reliability while adding minimal structural complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This configuration effectively minimizes leakage and enhances the selectivity of memory cells, leading to improved memory array performance and reliability by utilizing the resistive properties of ruthenium and silicon diodes to manage current flow more effectively.

Implementation Method 1

memory cells with a resistive element coupled in series with a diode, where the diodes contain ruthenium and silicon

Methodology Applied
Scientific EffectDiode rectification: Diode

Implementation Method 2

utilizing the resistive properties of ruthenium and silicon diodes to manage current flow more effectively

Methodology Applied
Scientific EffectElectrical resistance: Electrical Resistance

Data Source

PatentUS9343674B2Cross-point memory utilizing Ru/Si diode
Publication Date: 2016.05.17 MICRON TECHNOLOGY INC

AI summary

Memory devices utilizing memory cells including a resistive element and a diode coupled in series between two conductors. The diodes include a ruthenium material and a silicon material. The diodes further include an interface of ruthenium or ruthenium silicide between the silicon material and the ruthenium material.