Radiation Detector Redistribution Layer for Gap-Free Pixel Routing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional semiconductor radiation detectors suffer from gaps between detector modules and variations in pixel pitch, leading to incomplete radiation detection and distorted spatial resolution, particularly in imaging applications.
Innovation Solution
A radiation detector design with sensor tiles and ASICs connected via a redistribution layer, where conductor tracks cross over pixels with voids to minimize parasitic capacitance and maintain uniform signal-to-noise ratio, allowing for compact arrangement and reduced gaps between modules.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If multiple detector modules are assembled side by side to cover larger area, then the detection area is increased, but gaps occur between adjacent modules where radiation is not detected
Solution Approach 1:
The sensor tile is divided into multiple pixels that can be independently connected to ASIC input contacts. This segmentation allows flexible arrangement of detector modules while maintaining continuous coverage through proper conductor track routing between modules.
Solution Approach 2:
A redistribution layer with conductor tracks acts as an intermediary between pixels and ASIC input contacts. This intermediary structure enables continuous electrical connection across module boundaries, eliminating detection gaps at joints between adjacent modules.
2Measurement precision
If the pitch between input contacts is reduced to increase pixel density, then spatial resolution is improved, but parasitic capacitance increases affecting signal-to-noise ratio
Solution Approach 1:
The harmful parasitic capacitance effect is extracted and minimized by optimizing the conductor track geometry and routing. The redistribution layer design separates the signal path from sources of parasitic capacitance, allowing high pixel density while maintaining signal quality.
Solution Approach 2:
The conductor track parameters (width, spacing, length) are optimized to minimize parasitic capacitance. By changing these geometric parameters, the design achieves fine pitch spacing for high spatial resolution while controlling the harmful capacitance effect through parameter optimization.
3Object-affected harmful factors
If conductor tracks are routed directly under pixels to minimize capacitance, then signal-to-noise ratio is improved, but manufacturing complexity increases due to precise alignment requirements
Solution Approach 1:
The connection between pixels and ASIC input contacts is moved from a direct vertical alignment to a distributed routing approach in the horizontal plane. The redistribution layer allows conductor tracks to route laterally, reducing the need for precise vertical alignment while maintaining low parasitic capacitance through optimized track geometry.
4Measurement precision
If pixel pitch is reduced to increase number of pixels per area, then spatial resolution is improved, but the pitch mismatch between sensor pixels and ASIC input contacts increases
Solution Approach 1:
The redistribution layer serves as an intermediary that decouples the pixel pitch from the ASIC input contact pitch. Conductor tracks in the redistribution layer can stretch, compress, or route indirectly to match different pitches, allowing high-resolution sensors to be connected to standard ASICs without pitch mismatch problems.
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 design minimizes parasitic capacitance, reduces gaps, and maintains uniform signal-to-noise ratio, enhancing spatial resolution and coverage without undetected radiation, suitable for imaging applications.
Implementation Method 1
semiconductor detectors which either directly or indirectly convert incident radiation, i.e. incident photons or electrons, to an electrical charge proportional to the absorbed energy
Implementation Method 2
the charge created by the incident radiation is converted to a voltage in an ASIC with a charge sensitive amplifier. The amplitude of the resulting voltage signal as well as its underlying noise level are strongly influenced by the capacitance at the input of the amplifier
Data Source
Figure 1
Figure 2
Figure 3a
AI summary
A radiation detector for position-resolved detection of radiation is provided as well as a method of manufacturing such radiation detector. The radiation detector comprises at least one sensor tile (1) with sensor material sensitive to the radiation, the sensor tile (1) defining a horizontal plane; a set of pixels (2) of electrically conducting material in contact with the sensor material; at least one ASIC (5) with input contacts (4) in electrical connection with the pixels (2), wherein at least one input contact (4) is horizontally offset relative to a corresponding pixel (2); and a redistribution layer (10) between the at least one sensor tile (1) and the at least one ASIC (5), the redistribution layer (10) comprising conductor tracks (11) electrically connecting the input contacts (4) with the corresponding pixels (2). At least one of the conductor tracks (11) crosses at least one crossed pixel different from the corresponding pixel. At least one crossed pixel has a void (14) of the electrically conducting material corresponding to at least a portion of projections of the conductor tracks (11). In this way, parasitic capacitances between different pixels (2) are minimized or avoided, and the quality of the position-resolved image is improved.