Flexible NTC Thin-Film Thermistor for Fast Temperature Sensing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing NTC thermistors are too large for many applications, limiting their integration in electronic devices and hindering the development of more intelligent and secure end devices, as they occupy valuable space and do not offer the necessary flexibility and sensitivity.

Innovation Solution

The development of an NTC thin-film thermistor with extremely thin, flexible design featuring a functional ceramic with a spinel or perovskite structure and conductive ceramic electrodes, allowing for precise temperature measurement and reduced thermal mass, enabling improved response time and sensitivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of moving object

If conventional NTC thermistor construction is used, then temperature measurement function is achieved, but the device size is too large for miniaturized electronic applications

Engineering Contradiction:
Improvethermistor sizeVSAvoidmeasurement precision
Core Design Contradiction:
Length of moving objectVSReliability

Solution Approach 1:

The patent transitions from bulk three-dimensional thermistor construction to thin-film layered structure, reducing the thermistor thickness to the micrometer range while maintaining functional performance. This dimensional change enables miniaturization suitable for modern electronic devices while preserving temperature measurement capability through controlled film thickness and composition.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent employs thin-film technology to create flexible, bendable thermistor structures with thickness less than 10 μm. The thin-film construction on flexible substrates allows the device to be bent without mechanical damage, enabling new applications in flexible electronics and wearable devices while maintaining measurement precision.

Inventive Principle:
Principle #30Flexible shells and thin films

2Speed

If conventional thermistor thickness is used, then structural stability is maintained, but thermal mass is high resulting in slow response time

Engineering Contradiction:
Improveresponse timeVSAvoidmechanical stability
Core Design Contradiction:
SpeedVSStrength

Solution Approach 1:

The patent changes the thickness parameter from conventional dimensions to the micrometer range, reducing thermal mass and improving response time. The thin-film structure with controlled thickness enables faster thermal response while mechanical stability is maintained through appropriate substrate selection and film composition design.

Inventive Principle:
Principle #35Parameter changes

3Adaptability or versatility

If thin-film construction is used, then device flexibility and reduced thermal mass are achieved, but manufacturing precision requirements increase

Engineering Contradiction:
Improvedevice flexibilityVSAvoidfilm thickness control
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The patent utilizes thin-film deposition techniques to create flexible thermistor structures with controlled thickness in the micrometer range. The thin-film construction provides mechanical flexibility and bendability while standard deposition processes maintain sufficient thickness control for functional performance.

Inventive Principle:
Principle #30Flexible shells and thin films

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 thin-film design allows for precise temperature measurement, increased mechanical stability, and reduced electrical resistance, making it suitable for high-temperature applications and enabling new application possibilities by saving space in electronic devices.

Implementation Method 1

NTC thermistors are resistors with negative temperature coefficients that are frequently used as sensors for temperature measurement in electronic devices

Methodology Applied
Scientific EffectNegative temperature coefficient: Thermistor

Implementation Method 2

The NTC thin film comprises a single- or polycrystalline functional ceramic with a spinel or perovskite structure. Functional ceramics with a perovskite structure are particularly suitable for use at high temperatures, as the electrical properties of perovskite structures are less affected at high temperatures

Methodology Applied
Scientific EffectPerovskite crystal structure:

Data Source

PatentEP3994710B1Ntc thin film thermistor and method for producing an ntc thin film thermistor
Publication Date: 2024.09.18 TDK ELECTRONICS AG
  • EP3994710B1 patent drawingFigure 1~2
  • EP3994710B1 patent drawingFigure 3~4
  • EP3994710B1 patent drawingFigure 5

AI summary

The invention relates to an NTC thin film thermistor (1) which consists of at least a first thin film electrode (3a), at least an NTC thin film (2) and at least a second thin film electrode (3b). A further aspect of the invention relates to a method for producing an NTC thin film thermistor (1).