Plasmonic Photosensitive Sensor for Wet Fingerprint Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current fingerprint recognition sensors have low signal-to-noise ratio and sensitivity, particularly when residual water is present, limiting their effectiveness and user experience.

Innovation Solution

A photosensitive sensor is developed with a first type semiconductor layer, an intrinsic semiconductor layer containing dispersely distributed metal particles capable of generating a surface plasmon effect, and a second type semiconductor layer, which enhances light absorption and improves signal-to-noise ratio and sensitivity by utilizing surface plasmon effects to boost photocurrent.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional fingerprint recognition sensors are used, then the device structure is simple, but the signal-to-noise ratio and sensitivity are low

Engineering Contradiction:

Improvesignal-to-noise ratioVSAvoidsensor structure

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies composite materials by integrating metal particles (such as aluminum, silver, or gold) into the intrinsic semiconductor layer to form a composite structure. This composite material approach enables the generation of surface plasmon effects, which significantly enhance light absorption and improve the signal-to-noise ratio of the photosensitive sensor while maintaining a relatively simple overall device structure.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent changes the physical and chemical parameters of the sensor by introducing metal particles with specific properties (material composition, size distribution, spatial arrangement) into the intrinsic semiconductor layer. These parameter changes enable the surface plasmon effect, which transforms the optical response characteristics of the sensor and improves sensitivity without fundamentally altering the device architecture.

Inventive Principle:

Principle #35Parameter changes

2Measurement precision

If conventional photosensitive sensors are used, then the manufacturing process is simple, but the sensitivity is low particularly in environments with residual water

Engineering Contradiction:

ImprovesensitivityVSAvoidmanufacturing process

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent applies local quality by dispersing metal particles specifically within the intrinsic semiconductor layer rather than uniformly throughout the entire sensor structure. This localized modification concentrates the surface plasmon effect in the region most critical for light absorption and signal generation, thereby improving sensitivity without requiring complex manufacturing processes for the entire device.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The metal particles act as intermediaries that mediate between incident light and the semiconductor material. They convert optical energy into localized electromagnetic fields through surface plasmon resonance, which then interact with the semiconductor to generate enhanced photocurrent. This intermediary mechanism improves sensitivity while maintaining compatibility with existing manufacturing processes.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Reliability

If metal particles are added to enhance surface plasmon effect, then the signal-to-noise ratio improves, but the device complexity increases

Engineering Contradiction:

Improvesignal-to-noise ratioVSAvoidlayer structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies segmentation by dividing the intrinsic semiconductor layer into regions containing dispersed metal particles. This segmented approach allows the metal particles to be distributed throughout the layer rather than forming a continuous complex structure, thereby improving signal-to-noise ratio through multiple localized surface plasmon effects while maintaining manufacturing simplicity.

Inventive Principle:

Principle #1Segmentation

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 solution significantly improves the signal-to-noise ratio and sensitivity of the photosensitive sensor, enhancing user experience and operational effectiveness, especially in environments with residual water.

Implementation Method 1

The intrinsic semiconductor layer is provided with metal particles capable of generating a surface plasmon effect

Methodology Applied

Scientific EffectSurface plasmon effect: Surface Acoustic Wave

Implementation Method 2

photosensitive sensor includes a first type semiconductor layer, an intrinsic semiconductor layer disposed on a side of the first type semiconductor layer

Methodology Applied

Scientific EffectPhotoelectric effect: Photoelectric Effect

Data Source

PatentUS11757059B2Photosensitive sensor, manufacturing method thereof, and display panel

Publication Date: 2023.09.12 BOE TECHNOLOGY GROUP CO LTD

AI summary

A photosensitive sensor, a manufacturing method thereof and a display panel are provided. The photosensitive sensor includes a first type semiconductor layer, an intrinsic semiconductor layer disposed on a side of the first type semiconductor layer, and a second type semiconductor layer disposed on a side of the intrinsic semiconductor layer away from the first type semiconductor layer. The intrinsic semiconductor layer is provided with metal particles capable of generating a surface plasmon effect. The metal particles are dispersely distributed in the intrinsic semiconductor layer.