Flash Memory Security Architecture Using Sector Credentials

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current security measures for flash memory devices are inadequate to prevent hacking and data retrieval from non-volatile storage, especially as cyber threats become more sophisticated.

Innovation Solution

The implementation of fault detection circuits, address scrambling, dummy arrays, password protection, and improved manufacturing techniques enhances the security of flash memory devices by making it difficult for malicious actors to access stored data.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional flash memory storage is used, then data accessibility is maintained, but security against hacking is insufficient

Engineering Contradiction:
ImprovesecurityVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The flash memory array is divided into multiple independent sectors, each with its own security credentials stored in dedicated credential storage circuits. This segmentation allows individual sectors to be secured independently while maintaining overall system functionality, resolving the contradiction between security and complexity by distributing security mechanisms across multiple isolated units.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Credential verification circuits act as intermediaries between the host interface and the flash memory array. These circuits verify credentials before allowing access to data, providing a security layer that mediates between the external host and internal storage, thereby enhancing security without requiring the host to directly manage complex security protocols.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If security measures are added to prevent hacking, then data protection is improved, but manufacturing complexity increases

Engineering Contradiction:
ImprovesecurityVSAvoidmanufacturing ease
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The security credentials are integrated directly into the flash memory array structure during the manufacturing process, merging the credential storage functionality with the existing memory cell fabrication. This approach allows security features to be added without requiring separate manufacturing steps, thereby improving security while maintaining manufacturing ease.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The flash memory cells serve multiple functions: they store both user data and security credentials. This multi-functionality eliminates the need for separate dedicated security hardware, reducing manufacturing complexity while providing robust security through the same fabrication process used for standard memory cells.

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

3Reliability

If credential verification is implemented, then unauthorized access is prevented, but access speed is reduced

Engineering Contradiction:
Improveaccess controlVSAvoiddata access speed
Core Design Contradiction:
ReliabilityVSSpeed

Solution Approach 1:

Credential verification is performed in advance during the initialization phase, before actual data access operations. Once verified, the credentials enable subsequent read/write operations without repeated verification overhead, thus maintaining fast access speeds while ensuring secure authorization.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

After initial credential verification, the system skips repeated verification steps for subsequent operations within the same session. This allows the system to rush through multiple data access operations without the overhead of continuous verification, maintaining high-speed access while preserving security through the initial authorization check.

Inventive Principle:
Principle #21Skipping (Rushing through)

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

These security enhancements effectively prevent unauthorized access and data retrieval from flash memory chips, providing robust protection against hacking attempts.

Implementation Method 1

Memory cell 10 is erased, through a Fowler-Nordheim tunneling mechanism, by applying a high voltage on erase gate 28 with other terminals equal to zero volts. Electrons tunnel from floating gate 24 into erase gate 28

Methodology Applied
Scientific EffectFowler-Nordheim tunneling:

Implementation Method 2

Memory cell 10 is programmed, through a source side hot electron programming mechanism, by applying a high voltage on coupling gate 26, a high voltage on source line 14, a medium voltage on erase gate 28, and a programming current on bit line 20. A portion of electrons flowing across the gap between word line 22 and floating gate 24 acquire enough energy to inject into floating gate 24

Methodology Applied
Scientific EffectHot electron programming:

Data Source

PatentEP4134859B1Anti-hacking mechanisms for flash memory device
Publication Date: 2024.10.30 SILICON STORAGE TECHNOLOGY INC
  • EP4134859B1 patent drawingFigure 1
  • EP4134859B1 patent drawingFigure 2
  • EP4134859B1 patent drawingFigure 3

AI summary

Multiple embodiments are disclosed for enhancing security and preventing hacking of a flash memory device. The embodiments prevent malicious actors from hacking a flash memory chip to obtain data that is stored within the chip. The embodiments include the use of fault detection circuits, address scrambling, dummy arrays, password protection, improved manufacturing techniques, and other mechanisms.