Plasmonic Channel Array for Nanoparticle Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current microscopy techniques face challenges in achieving sub-wavelength resolution for optical detection of small particles, particularly nanoparticles, due to limitations in near-field microscopy solutions and the difficulty in industrial-scale production and reproducibility.

Innovation Solution

The use of a system comprising metallic plasmonic channels arranged in a fan shape around a viewing zone, with spatial characteristics that allow for the transfer of optical information from a sub-wavelength near-field zone to a far-field zone, enabling sub-wavelength resolution microscopy through an original arrangement of metallic plasmonic channels and optical signal decoupling means.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If near-field microscopy solutions are used to achieve sub-wavelength resolution, then measurement precision is improved, but device complexity and difficulty of industrial production increase

Engineering Contradiction:
ImproveresolutionVSAvoidcomplexity of near-field microscopy system
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system is divided into distinct functional modules: a substrate with integrated metal wires, separate optical detection means, and optional fluidic channels. This segmentation allows each component to be optimized independently and facilitates industrial manufacturing through standardized production of substrate arrays.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The metal wires serve multiple functions simultaneously: they act as plasmonic structures for sub-wavelength resolution, provide electrical connectivity for detection, and can be integrated with fluidic channels for particle delivery. This multi-functionality reduces overall system complexity.

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

2Measurement precision

If manual placement of sample and exploration area is used in near-field microscopy, then measurement precision is maintained, but productivity decreases

Engineering Contradiction:
Improvedetection accuracyVSAvoidproduction rate
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

Multiple detection systems are pre-manufactured on a single substrate in parallel, with all necessary components (metal wires, optical interfaces, fluidic connections) prepared in advance. This eliminates the need for manual assembly and positioning during operation, significantly increasing throughput while maintaining detection accuracy.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention uses arrays of identical detection systems replicated on a single substrate. Each detection element is a copy of the optimized single-wire design, allowing mass production through standardized fabrication processes while maintaining the sub-wavelength resolution capability of each individual detector.

Inventive Principle:
Principle #26Copying

3Device complexity

If sub-wavelength details are filtered in far-field microscopy, then device complexity is reduced, but measurement precision deteriorates

Engineering Contradiction:
Improvesimplicity of optical systemVSAvoidresolution
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The metal wires act as an intermediary structure between the far-field optical detection system and the near-field sub-wavelength information. They serve as a bridge that converts evanescent near-field components into propagating far-field components, allowing simple far-field optics to access high-resolution near-field information without requiring complex near-field scanning mechanisms.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Measurement precision

If plasmonic structures are optimized for maximum spatial frequency, then measurement precision is improved, but manufacturing precision requirements increase

Engineering Contradiction:
Improvespatial frequency detectionVSAvoidmetal thickness control
Core Design Contradiction:
Measurement precisionVSManufacturing precision

Solution Approach 1:

The invention optimizes the metal wire thickness to approximately 12 nanometers, a parameter that maximizes plasmonic spatial frequency transmission while remaining compatible with standard nanofabrication techniques. This specific thickness parameter balances the competing requirements of high-resolution detection and manufacturability using conventional semiconductor processing methods.

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 solution allows for the detection of particles with nanometric dimensions by coupling a sub-wavelength near-field zone to a setback zone, radiating optical information for capture in the far field, thereby achieving sub-wavelength resolution microscopy suitable for industrial production.

Implementation Method 1

The system comprises an optical detection means as well as a set of metal wires arranged in the same plane and one end of which is sufficiently close to a viewing zone to allow transfer of optical information through said metal wires

Methodology Applied
Scientific EffectPlasmon coupling:

Implementation Method 2

the local part of the electromagnetic field containing the highest spatial frequencies (near field) is coupled to the structured matter. These frequencies, carrying the most spatially detailed information, cannot indeed propagate towards deep space and only give rise to evanescent waves

Methodology Applied
Scientific EffectNear-field to far-field conversion:

Data Source

PatentEP2396642B1System and equipment for particle detection with a fan for outcoupling of optical information and corresponding manufacturing procedure.
Publication Date: 2015.04.08 CENT NAT DE LA RECH SCI (C N R S)
  • EP2396642B1 patent drawingFigure 1~2
  • EP2396642B1 patent drawingFigure 3~4
  • EP2396642B1 patent drawingFigure 5~6

AI summary

The present invention relates to a system (1) for optical detection of particles (10) arranged in a viewing area (11) suitable for being illuminated by radiation with a predetermined wavelength. Said system comprises a means (4) for optical detection, as well as an assembly (5) of metal plasmonic channels (5', 5", 5'") arranged in a single plane (XY) and in which one end (6', 6", 6'") is close enough to the viewing area (11) to allow optical information to be transferred from one end to the other of said channels (5', 5", 5'"). In said system, the channels (5', 5", 5'") are arranged such that the assembly (5) forms an array (5) for transferring optical information around the viewing area (11). The value of at least one spatial characteristic of the array (5) is respectively lower and higher than the wavelength near the ends (6', 6", 6'") of the channels (5, 5", 5'") that are respectively close to and far away from the viewing area (11). The system comprises a means (8', 8", 8"') for optical decoupling between said ends (7', 7", 7'") that are far away from the viewing area (11) and the means (4) for optical detection. The present invention also relates to a device (40) for optical detection of particles (10) as well as to methods for manufacturing such a system and such a device.