Wafer-Scale Radiation Detector with Sealed Gas Cavity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
State-of-the-art radiation detection systems, such as Geiger counters, are cumbersome and impractical for real-time tracking due to their large size, and smaller-scale detectors face challenges in sealing gases during fabrication.
Innovation Solution
A multi-layer structure is fabricated on a wafer with metal, sacrificial, and insulating layers to form a cavity, which is then filled with ionizable gas and sealed using vias and encapsulating layers, enabling the creation of a small-scale radiation detector that can detect ionizing radiation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If traditional Geiger counters are used for radiation detection, then detection capability is achieved, but the device size becomes large and cumbersome
Solution Approach 1:
The patent transitions from a two-dimensional planar seal to a three-dimensional encapsulated cavity structure. By creating a vertical cavity within the multi-layer structure and sealing it with encapsulating layers, the gas-containing volume is isolated in three dimensions, enabling small-scale detector design while maintaining reliable gas containment.
Solution Approach 2:
The patent employs a multi-layer composite structure comprising conductive layers, insulating layers, sacrificial layers, and encapsulating layers. Each layer serves a specific function, and their combination creates a compact yet reliable sealed cavity that maintains gas containment while minimizing overall device volume.
2Volume of moving object
If the device size is reduced for portability, then real-time tracking becomes practical, but sealing the gas within the detector becomes difficult
Solution Approach 1:
The patent performs preliminary actions during fabrication by forming the sealed cavity structure before final assembly. The encapsulating layers are deposited to seal the cavity, and vias are filled and sealed to trap the gas inside, ensuring gas containment is established early in the manufacturing process rather than requiring complex post-assembly sealing.
Solution Approach 2:
The patent uses sacrificial layers as intermediary structures during fabrication. These sacrificial layers are deposited, patterned, and then removed to create the sealed cavity space. They serve as temporary mediators that enable cavity formation while maintaining structural integrity during the manufacturing process, after which they are selectively removed to leave the final sealed structure.
3Reliability
If a multi-layer structure with sacrificial layers is used to form a cavity, then gas sealing becomes feasible, but manufacturing process complexity increases
Solution Approach 1:
The patent segments the fabrication process into distinct stages: depositing conductive layers for electrodes, depositing insulating layers for isolation, depositing sacrificial layers for cavity formation, removing sacrificial layers to create cavities, filling cavities with gas, and sealing with encapsulating layers. This segmentation allows each step to be optimized independently while maintaining overall process reliability.
Solution Approach 2:
The patent employs a nested structure where the cavity is formed within the multi-layer structure by removing sacrificial layers that were deposited between functional layers. The gas is then nested within this cavity, and the entire structure is encapsulated, creating a nested configuration where the gas-containing cavity is embedded within the sealed multi-layer structure.
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 solution results in a compact radiation detector capable of real-time tracking of radiation emissions, suitable for embedding in small items like a driver's license or mobile phone, providing simultaneous radiation measurement and location data, particularly beneficial for first responders.
Implementation Method 1
filling the cavity with a gas that ionizes in response to nuclear radiation
Data Source
AI summary
A method for a constructing radiation detector includes fabricating a multi-layer structure upon a wafer, the multi-layer structure comprising a plurality of metal layers, a plurality of sacrificial layers, and a plurality of insulating layers, forming a cavity within the multi-layer structure, filling the cavity with a gas that ionizes in response to nuclear radiation, and sealing the gas within the cavity.