PUF Memory Cell Oxide Asymmetry for Random Code Generation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing technologies fail to effectively generate and amplify the necessary complexity and efficiency in generating unique and secure random codes, particularly in the field of semiconductor devices, and existing methods have not efficiently generate PUF codes, and existing methods are inefficient in addressing the amplification of random electronic noise in semiconductor devices, and existing methods lack effective integration of preparation and amplification of random codes.

Innovation Solution

The PUF codes generating apparatus and method, particularly to a physical unclonable function (PUF) code generating apparatus and a physical unclonable function (PUF) code generating method, particularly to a physical unclonable function (PUF) code generating apparatus and a physical unclonable function (PUF) code generating apparatus and a physical unclonable function (PUF) code generating method, which can randomly generate PUF codes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If existing flash memory is modified to amplify random electronic noise, then randomness of generated codes is improved, but device complexity and process complexity increase

Engineering Contradiction:

Improverandomness of generated codesVSAvoidcircuit complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent changes the geometric parameters of the tunnel oxide layer by controlling the corner ratio to be less than 0.99, creating thickness variation between central and peripheral areas. This parameter change directly generates random electronic noise without requiring complex additional circuits, thus improving randomness while avoiding increased device complexity

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent intentionally creates an asymmetric tunnel oxide layer structure where the corner ratio (minimum thickness of peripheral area to maximum thickness of central area) is less than 0.99. This asymmetric structure generates random electronic noise due to the thickness variation, achieving improved randomness without adding complex symmetric circuitry

Inventive Principle:

Principle #4Asymmetry

2Reliability

If existing flash memory is modified to amplify random electronic noise, then randomness of generated codes is improved, but manufacturing process complexity increases

Engineering Contradiction:

Improverandomness of generated codesVSAvoidprocess complexity

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent achieves randomness amplification by changing the manufacturing parameters of the tunnel oxide layer formation process, specifically controlling the corner ratio to be less than 0.99. This parameter change is integrated into the existing flash memory manufacturing process, avoiding the need for additional complex process steps while improving the randomness of generated codes

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If tunnel oxide layer thickness is varied to generate random codes, then PUF code generation capability is improved, but manufacturing precision requirements increase

Engineering Contradiction:

ImprovePUF code generation capabilityVSAvoidtunnel oxide layer thickness control

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent specifies that the corner ratio of the tunnel oxide layer should be less than 0.99, creating a controlled asymmetric structure. This asymmetric design intentionally generates random electronic noise while providing clear manufacturing guidelines, balancing PUF code generation capability with achievable manufacturing precision requirements

Inventive Principle:

Principle #4Asymmetry

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

The PUF code generating apparatus and a PUF code generating method, which can randomly generate PUF codes.

Implementation Method 1

amplify the random electronic noise generated by the thickness of the tunnel oxide layer determined by different production processes

Methodology Applied

Scientific EffectQuantum tunneling:

Data Source

PatentEP4447381B1Physical unclonable function code generating apparatus and method

Publication Date: 2025.12.17 WINBOND ELECTRONICS CORP

Figure 1
Figure 2A~2B
Figure 2C~3

AI summary

A physical unclonable function (PUF) code generating apparatus (100) includes a PUF code generating element (110) and a PUF code storage element (120). The PUF code generating element (110) is configured to generate a PUF code (210, 220, 230). The PUF code storage element (120) is coupled to the PUF code generating element (110). The PUF code storage element (120) is configured to receive and store the PUF code (210, 220, 230). The PUF code generating element (110) includes multiple first memory cells (112). Each of the first memory cells (112) includes a gate layer, a semiconductor layer (AA), and a tunnel oxide layer (Tox). The tunnel oxide layer (Tox) is located between the gate layer and the semiconductor layer (AA). The tunnel oxide layer (Tox) includes a central area (310) and a peripheral area (320). A ratio (T2/T1) of a minimum thickness (T2) of the peripheral area (320) to a maximum thickness (T1) of the central area (310) of the tunnel oxide layer (Tox) is defined as a corner ratio (C), and the corner ratio (C) is less than 0.99.