On-Chip Lens Groove Bottom Surface Shape for Image Quality

Solution Overview

Problem

The existing solid-state imaging apparatuses face image quality degradation due to light incident on light blocking films from grooves between on-chip lenses, which causes color mixture and reduces sensitivity.

Innovation Solution

A solid-state imaging apparatus with grooves between lenses, where the groove's bottom surface is shaped to protrude downward, and the groove includes a first portion between two adjacent lenses and a second portion between four adjacent lenses, with a lower end of the second portion positioned lower than the first portion, to direct light towards color filters rather than light blocking films, and the use of anti-reflection films and refractive index-matched films to minimize light leakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If grooves are provided between adjacent on-chip lenses to prevent color mixture, then color mixture between pixels is suppressed, but light may be incident on light blocking film from the groove, degrading image quality

Engineering Contradiction:

Improvecolor mixture preventionVSAvoidimage quality degradation

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The groove bottom surface is shaped to protrude downward, changing the geometric parameters of the groove structure. This modification redirects light paths so that light incident on the groove is directed toward color filters rather than onto the light blocking film, thereby preventing image quality degradation while maintaining color mixture prevention

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The groove structure, which initially causes harmful light incidence on the light blocking film, is transformed into a beneficial element by shaping its bottom surface to protrude downward. This conversion redirects the previously harmful light paths toward color filters, turning the groove from a source of image quality degradation into a component that enhances light utilization

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Object-affected harmful factors

If the groove bottom surface is shaped to protrude downward to direct light towards color filters, then image quality degradation is suppressed, but the groove structure becomes more complex

Engineering Contradiction:

Improveimage quality degradationVSAvoidgroove structure complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The groove bottom surface is shaped to protrude downward, changing the geometric parameters of the groove structure. This modification redirects light paths so that light incident on the groove is directed toward color filters rather than onto the light blocking film, thereby preventing image quality degradation while maintaining color mixture prevention

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The groove structure is extended into the vertical dimension by making the bottom surface protrude downward. This dimensional change creates a three-dimensional profile that redirects light paths without requiring additional lateral components, thereby managing light control in a cost-effective manner

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Shape

If the groove lower end is positioned lower than the first portion to enable point-like planar shape between four lenses, then light direction control is improved, but manufacturing precision requirements increase

Engineering Contradiction:

Improvegroove planar shapeVSAvoidgroove formation precision

Core Design Contradiction:

ShapeVSManufacturing precision

Solution Approach 1:

The groove bottom surface is shaped to protrude downward, changing the geometric parameters of the groove structure. This modification redirects light paths so that light incident on the groove is directed toward color filters rather than onto the light blocking film, thereby preventing image quality degradation while maintaining color mixture prevention

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The groove bottom surface is shaped with curved profiles (semi-circular, triangular, or trapezoidal cross-sections) to create the protruding downward shape. These curved geometries facilitate light redirection while being amenable to standard semiconductor manufacturing processes such as etching, thereby balancing shape requirements with manufacturing feasibility

Inventive Principle:

Principle #14Spheroidality (Curvature)

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 configuration effectively suppresses image quality degradation by directing light towards color filters, reducing color mixture and maintaining high sensitivity, while also preventing light from entering adjacent lenses, thus enhancing the overall performance of the imaging apparatus.

Implementation Method 1

the groove includes a bottom surface shaped to protrude downward... the bottom surface shaped to protrude downward can suppress degradation of image quality caused by the groove between the lenses... direct light towards color filters rather than light blocking films

Methodology Applied

Scientific EffectLight refraction and reflection: Refraction

Data Source

PatentUS20230026747A1Solid-state imaging apparatus and method for manufacturing the same

Publication Date: 2023.01.26 SONY SEMICON SOLUTIONS CORP

AI summary

[Object] A solid-state imaging apparatus that can suppress degradation of image quality caused by a groove between lenses is provided, and a method for manufacturing the solid-state imaging apparatus is also provided.[Solving Means]A solid-state imaging apparatus according to the present disclosure includes multiple photoelectric conversion sections, and multiple lenses provided above the multiple photoelectric conversion sections. The multiple lenses each include a groove provided between the lenses, and the groove includes a bottom surface shaped to protrude downward.