Image Sensor Side-Contact Electrode Layout for Spectral Switching

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Multilayer image sensors face challenges in maintaining the sensitivity and spectral sensitivity characteristics of photoelectric conversion films due to material reactivity with oxygen, ozone, or moisture, requiring complex and costly fabrication processes under inert atmospheres, and existing solutions complicate the connection between voltage control elements and transparent electrodes.

Innovation Solution

The image sensor design features a connection layer that aligns with the side surfaces of a transparent electrode and photoelectric conversion film, reducing resistance in the voltage application path and allowing for easier handling, with a fabrication method that patterns these layers to minimize exposure to reactive gases, eliminating the need for additional openings in the insulating layer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the photoelectric conversion film is exposed to oxygen, ozone, or moisture during fabrication, then the fabrication process becomes simpler and less costly, but the sensitivity and spectral sensitivity characteristics of the photoelectric conversion film deteriorate

Engineering Contradiction:

Improvefabrication process simplicityVSAvoidphotoelectric conversion film performance

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

An insulating layer is formed on the photoelectric conversion film before exposure to reactive gases during subsequent fabrication steps. This preliminary protective action prevents deterioration while allowing simpler fabrication processes to proceed, resolving the contradiction between ease of manufacture and reliability

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The insulating layer acts as an intermediary barrier between the photoelectric conversion film and harmful reactive gases (oxygen, ozone, moisture). It allows the fabrication process to proceed in ambient conditions while protecting the sensitive photoelectric conversion film from deterioration

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If additional openings are provided in the insulating layer to connect the control electrode to the transparent electrode, then electrical connection is achieved, but the device complexity and fabrication cost increase

Engineering Contradiction:

Improveelectrical connectionVSAvoidfabrication process complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

Instead of creating vertical openings through the insulating layer (z-dimension approach), the connection layer is formed to extend along the side surface of the transparent electrode, utilizing the lateral dimension. This dimensional shift eliminates the need for complex opening formation while achieving reliable electrical connection

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

Rather than forming openings in the insulating layer to achieve connection (conventional approach), the connection layer is formed to wrap around and contact the side surface of the transparent electrode. This inverted approach simplifies fabrication by avoiding opening formation while maintaining electrical connectivity

Inventive Principle:

Principle #13The other way round (Inversion)

3Reliability

If the connection layer contacts the top surface of the transparent electrode, then electrical connection is established, but light blocking occurs and detection accuracy deteriorates

Engineering Contradiction:

Improveelectrical connectionVSAvoidlight detection accuracy

Core Design Contradiction:

ReliabilityVSMeasurement precision

Solution Approach 1:

The connection layer is segmented into distinct functional zones: one portion contacts the side surface of the transparent electrode for electrical connection, while another portion contacts the control electrode. This segmentation allows electrical connection without light-blocking contact on the top surface, resolving the contradiction between connection reliability and detection precision

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS11955493B2Image sensor including control electrode, transparent electrode, and connection layer electrically connecting control electrode to side surface of transparent electrode

Publication Date: 2024.04.09 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

AI summary

An image sensor includes pixel electrodes, a control electrode, a photoelectric conversion film arranged on the pixel electrodes, a transparent electrode arranged on the photoelectric conversion film, an insulating layer arranged on at least a portion of a top surface of the transparent electrode, and a connection layer that electrically connects the control electrode to the transparent electrode. The connection layer is in contact with at least one side surface of the transparent electrode. A side surface of the insulating layer, the at least one side surface of the transparent electrode, and a side surface of the photoelectric conversion film are aligned with each other.