Indolocarbazole Buffer Layer for Organic Imaging Element Reliability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing imaging technologies face limitations in improving image quality and reliability, particularly in organic imaging elements, where further enhancements are needed to address issues such as dark current, SN ratio, afterimage characteristics, and heat resistance.

Innovation Solution

Incorporating an indolocarbazole derivative as a first buffer layer in the imaging element, which includes a photoelectric conversion layer with a p-type semiconductor, to enhance the SN ratio, afterimage characteristics, and reliability under simultaneous application of light, voltage, and heat loads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional organic photoelectric conversion elements are used, then basic imaging function is achieved, but image quality and reliability cannot be further improved

Engineering Contradiction:

ImprovereliabilityVSAvoidimage quality improvement potential

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

The patent changes the chemical structure parameter of the organic semiconductor material by introducing an indolocarbazole derivative with specific molecular characteristics (large-sized mother skeleton, intramolecular symmetry, 5-membered pyrrole ring). This structural parameter change leads to improved reliability and suppressed electric characteristic deterioration under light, voltage, and heat loads.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite structure by combining the indolocarbazole derivative with specific p-type semiconductors (having HOMO levels of -5.6 eV to -5.7 eV) in the photoelectric conversion layer. This composite material approach achieves synergistic effects that improve both image quality and reliability beyond what conventional single materials can provide.

Inventive Principle:

Principle #40Composite materials

2Ease of manufacture

If organic photoelectric conversion materials are used, then flexibility and manufacturing ease are improved, but dark current and afterimage characteristics deteriorate

Engineering Contradiction:

Improvemanufacturing easeVSAvoiddark current

Core Design Contradiction:

Ease of manufactureVSObject-generated harmful factors

Solution Approach 1:

The patent optimizes the HOMO level parameter of the p-type semiconductor to specifically -5.6 eV to -5.7 eV, which creates an energy barrier that suppresses dark current generation while maintaining the ease of organic material manufacturing processes.

Inventive Principle:

Principle #35Parameter changes

3Weight of moving object

If organic photoelectric conversion elements are used, then weight reduction is achieved, but heat resistance and electric characteristic stability under heat load worsen

Engineering Contradiction:

ImproveweightVSAvoidheat resistance

Core Design Contradiction:

Weight of moving objectVSTemperature

Solution Approach 1:

The patent combines the indolocarbazole derivative (with its thermally stable molecular structure) with p-type semiconductors having specific HOMO levels to create a composite organic photoelectric conversion layer. This composite structure maintains the light weight advantage of organic materials while achieving improved heat resistance and electric characteristic stability under simultaneous light, voltage, and heat loads.

Inventive Principle:

Principle #40Composite materials

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 use of an indolocarbazole derivative in the first buffer layer improves the initial characteristics and reliability of the imaging element, suppressing electric characteristic deterioration even under continuous exposure to light, voltage, and heat, while maintaining transparency and absorption characteristics.

Implementation Method 1

a first organic semiconductor material including an indolocarbazole derivative and disposed between the upper electrode and the lower electrode

Methodology Applied

Scientific EffectElectron blocking:

Implementation Method 2

a photoelectric conversion layer disposed between the upper electrode and the lower electrode

Methodology Applied

Scientific EffectPhotoelectric conversion: Photoelectric Effect

Data Source

PatentUS10886335B2Imaging element, stacked-type imaging element, imaging apparatus and electronic apparatus

Publication Date: 2021.01.05 SONY GROUP CORP

AI summary

There is provided an imaging device including an upper electrode; a lower electrode; a photoelectric conversion layer disposed between the upper electrode and the lower electrode; and a first organic semiconductor material including an indolocarbazole derivative and disposed between the upper electrode and the lower electrode. Further, there is provided an electronic apparatus including an imaging device that includes an upper electrode; a lower electrode; a photoelectric conversion layer disposed between the upper electrode and the lower electrode; and a first organic semiconductor material including an indolocarbazole derivative and disposed between the upper electrode and the lower electrode.