Optical Sensor Waveguide Refractive Index Stacking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Optical sensors face challenges in enhancing quantum efficiency and reducing size while maintaining performance, particularly in directing and confining light within the sensor matrix for effective light detection and analysis.
Innovation Solution
The optical sensor design incorporates a waveguide region with a grating structure and dielectric layers to direct and confine light, using a conductive pad and reflective layers to optimize light propagation and detection efficiency, allowing for improved quantum efficiency and reduced size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If the optical sensor size is reduced, then the device compactness is improved, but the quantum efficiency deteriorates due to limited space for light detection
Solution Approach 1:
The patent transitions from planar light detection to three-dimensional light confinement using stacked dielectric layers with varying refractive indices. This vertical stacking creates multiple reflection interfaces that trap light in the third dimension, allowing efficient light detection within a compact footprint by utilizing the depth dimension for light confinement rather than requiring larger lateral areas.
Solution Approach 2:
The patent employs composite dielectric layer structures with different refractive indices (first dielectric layer, second dielectric layer, third dielectric layer) to create optical waveguiding and confinement. This composite material approach enables effective light trapping and enhanced quantum efficiency within the limited sensor volume by optimizing optical path lengths through material composition rather than increasing physical size.
2Reliability
If quantum efficiency is enhanced through additional light confinement structures, then light detection capability is improved, but device complexity increases
Solution Approach 1:
The patent integrates the light confinement function directly into the sensor stack by combining multiple dielectric layers with different refractive indices within the same structural footprint. Rather than adding separate external light trapping components, the confinement structures are merged with the sensor architecture itself, achieving enhanced quantum efficiency without proportionally increasing device complexity.
Solution Approach 2:
The dielectric layers serve multiple functions simultaneously: they provide electrical isolation, mechanical support, and optical confinement through refractive index differences. This multi-functionality reduces the need for additional dedicated light trapping components, thereby improving quantum efficiency while limiting the increase in overall device complexity.
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 design enhances the quantum efficiency of the optical sensor by effectively guiding and confining light, leading to improved light detection and analysis capabilities while minimizing the sensor's size.
Implementation Method 1
a waveguide region configured to guide light from a wave insert portion (20) through a waveguide portion (278) to a sample holding portion (23)
Implementation Method 2
a waveguide region with a grating structure and dielectric layers to direct and confine light
Implementation Method 3
using a conductive pad and reflective layers to optimize light propagation and detection efficiency
Implementation Method 4
Quantum efficiency is a ratio of a number of charge carriers collected by the optical sensor to a number of photons of a given energy incident on the optical sensor
Data Source
AI summary
Some embodiments of the present disclosure provide an optical sensor. The optical sensor includes a semiconductive substrate; a light sensing region on the semiconductive substrate; a waveguide region configured to guide light from a wave insert portion through a waveguide portion and to a sample holding portion; and an interconnect region below the waveguide region, and the interconnect region being disposed above the light sensing region. The waveguide portion includes a first dielectric layer comprising a first refractive index and at least one second dielectric layer comprising a second refractive index, wherein the second refractive index is smaller than the first refractive index.