Semiconductor IR and Color Sensor Shared Pixel Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current semiconductor devices that simultaneously sense images in the color and infra-red bands often require a larger size due to separate spaces for color and IR sensing circuits, which can limit their miniaturization and increase complexity.
Innovation Solution
A semiconductor device design that includes a lens, a first sensor for infra-red light, a second sensor for visible light, and a shared pixel circuit connected via an intermediate connector, where the IR and color sensors are formed as independent layers, allowing them to overlap and share a common footprint, thereby reducing the device's size and improving IR sensing quality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If separate spaces are allocated for color sensing circuit and IR sensing circuit, then both color and IR sensing functions can be achieved, but the device size increases
Solution Approach 1:
The patent combines the color sensing circuit and IR sensing circuit into a shared pixel structure where both sensing functions coexist within the same pixel unit. The color filter array and IR filter are positioned over different regions of the same pixel, allowing both color and IR signals to be generated and processed within a single integrated circuit footprint, thereby eliminating the need for separate dedicated spaces for each sensing function.
Solution Approach 2:
The pixel circuit is designed to serve multiple functions by simultaneously processing both color band signals and IR band signals. The same pixel circuit infrastructure handles both types of sensing data, making the circuit universal for dual-band operation. This multi-functionality allows a single pixel unit to replace what would traditionally require separate color sensor pixels and IR sensor pixels.
2Reliability
If separate pixel circuits are used for color and IR sensing, then sensing quality can be optimized, but device complexity increases
Solution Approach 1:
The patent merges the signal processing paths for color and IR sensing into a shared pixel circuit. Both the color photodiode and IR photodiode within the same pixel unit feed into common circuit elements including transfer transistors, floating diffusion nodes, and readout circuitry. This shared architecture reduces the total number of discrete circuit components while maintaining dedicated sensing regions for each band.
Solution Approach 2:
The patent segments the pixel structure at the sensing element level, where color and IR sensing are separated through spatial segmentation of filters and photodiodes within the pixel, while the downstream circuit processing is combined and shared. This segmentation allows optimized sensing for each band without requiring completely separate processing circuits.
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 reduces the overall size of the semiconductor device while maintaining or improving the quality of IR sensing by allowing the IR and color sensors to share a pixel circuit and occupy a common area, thus enhancing the device's efficiency and compactness.
Implementation Method 1
a lens configured to focus incident light
Implementation Method 2
an IR photodiode configured to sense an infra-red portion of the focused incident light... configured to convert the sensed infra-red portion of the focused incident light into a first electrical signal
Implementation Method 3
a color photodiode configured to sense a visible portion of the focused incident light... configured to convert the sensed visible portion of the focused incident light into a second electrical signal
Data Source
AI summary
A semiconductor device may include a first sensor configured to sense light having a wavelength within a first wavelength range from incident light and generates a first electrical signal based on the sensed light and a second sensor configured to sense light having a wavelength within a second, different wavelength range from the incident light and generates a second electrical signal based on the sensed light. The first and second sensors may be electrically connected to each other via an intermediate connector, and the first sensor and the second sensor may share a pixel circuit that is electrically connected thereto via the intermediate connector. The first and second wavelength ranges may include infra-red and visible wavelength ranges, respectively. The first and second wavelength ranges may include different visible wavelength ranges.