Ferroelectric Memory Cell Structure With Oxygen Vacancy Profiling

Solution Overview

Problem

The integration of non-volatile memory technologies in the semiconductor industry faces challenges in controlling oxygen vacancies, which can lead to uncontrolled variations in ferroelectric properties, affecting data retention and leakage current in memory cells.

Innovation Solution

A memory cell design that includes a controlled introduction of oxygen vacancies in a ferroelectric capacitor structure to enhance polarizability and switching properties, using techniques such as varying oxygen vacancy profiles and dopant layers to stabilize remanent-polarizable crystal structures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Speed

If oxygen vacancies are introduced in ferroelectric capacitor structure, then polarizability and switching properties are enhanced, but uncontrolled variations in ferroelectric properties occur affecting data retention and leakage current

Engineering Contradiction:

Improveswitching speedVSAvoiddata retention

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The patent applies local quality by creating distinct regions with different oxygen vacancy concentrations within the ferroelectric capacitor structure. Specifically, it introduces a first region with a first concentration of oxygen vacancies and a second region with a second concentration, allowing different parts of the same material to have different properties optimized for their specific functions - one region for enhanced switching and another for stable data retention

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs parameter changes by systematically varying the concentration of oxygen vacancies in different regions of the ferroelectric capacitor. By controlling the oxygen vacancy concentration as a key parameter, the invention optimizes the balance between switching speed and data retention, demonstrating how parameter adjustment can resolve technical contradictions

Inventive Principle:

Principle #35Parameter changes

2Speed

If oxygen vacancies are introduced in ferroelectric capacitor structure, then switching properties are enhanced, but leakage current increases

Engineering Contradiction:

Improveswitching speedVSAvoidleakage current

Core Design Contradiction:

SpeedVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by creating distinct regions with different oxygen vacancy concentrations within the ferroelectric capacitor structure. Specifically, it introduces a first region with a first concentration of oxygen vacancies and a second region with a second concentration, allowing different parts of the same material to have different properties optimized for their specific functions - one region for enhanced switching and another for stable data retention

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent converts the harmful effect of oxygen vacancies (which typically increase leakage current) into a beneficial feature by strategically positioning and controlling their concentration. Instead of avoiding oxygen vacancies entirely, the invention uses them in specific regions to enhance switching properties while managing their harmful effects through spatial distribution control

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Quantity of substance

If oxygen vacancies are introduced in ferroelectric capacitor structure, then polarizability is enhanced, but ferroelectric properties become unstable

Engineering Contradiction:

ImprovepolarizabilityVSAvoidferroelectric properties stability

Core Design Contradiction:

Quantity of substanceVSStability of the object's composition

Solution Approach 1:

The patent applies local quality by creating distinct regions with different oxygen vacancy concentrations within the ferroelectric capacitor structure. Specifically, it introduces a first region with a first concentration of oxygen vacancies and a second region with a second concentration, allowing different parts of the same material to have different properties optimized for their specific functions - one region for enhanced switching and another for stable data retention

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs parameter changes by systematically varying the concentration of oxygen vacancies in different regions of the ferroelectric capacitor. By controlling the oxygen vacancy concentration as a key parameter, the invention optimizes the balance between switching speed and data retention, demonstrating how parameter adjustment can resolve technical contradictions

Inventive Principle:

Principle #35Parameter changes

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 approach improves data retention and reduces leakage current by stabilizing ferroelectric properties, enabling faster switching and more stable polarization states in memory cells.

Implementation Method 1

a type of memory cell may include a thin film of ferroelectric material, whose polarization state may be changed in a controlled fashion to store data in the memory cell

Methodology Applied

Scientific EffectFerroelectric polarization: Polarisation

Data Source

PatentUS20240381660A1Memory cell, capacitive memory structure, and methods thereof

Publication Date: 2024.11.14 FERROELECTRIC MEMORY GMBH

AI summary

According to various aspects a memory cell is provided, the memory cell including: a first electrode; a second electrode; and a memory layer disposed between the first electrode and the second electrode, wherein the memory layer includes a first memory portion having a first concentration of oxygen vacancies and a second memory portion having a second concentration of oxygen vacancies different from the first concentration of oxygen vacancies.