SiPM Pixel Arrangement with Ceramic Cavity Interconnects
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional silicon photomultiplier (SiPM) arrays face challenges with low tile fill factor due to gaps between pixels required for wire-bonding, leading to reduced photon detection efficiency and increased complexity in compact arrangements.
Innovation Solution
A pixel arrangement where pixels are closely tiled with electrical interconnections that allow for direct communication between conducting terminals external to the pixel, eliminating the need for gaps and enabling compact tiling and high fill factor through auxiliary metal lines for read-out signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional SiPM pixels are packaged with separate SMT packages, then each pixel can be individually mounted and connected, but the tile fill factor decreases due to edge consumption and gaps between packages
Solution Approach 1:
Multiple SiPM pixel dies are mounted adjacent to each other on a single ceramic cavity without individual SMT packages, merging what were previously separate packaged units into an integrated array structure, thereby eliminating package edges and gaps that consumed active area
Solution Approach 2:
The ceramic cavity serves multiple functions: it acts as the substrate for mounting pixel dies, provides electrical insulation between adjacent pixels, and serves as the final packaged unit itself, eliminating the need for separate SMT packaging while maintaining manufacturability
2Ease of manufacture
If gaps are introduced between pixel dies to accommodate bonding pads and wire-bonding, then electrical connections can be established, but the tile fill factor and photon detection efficiency are reduced
Solution Approach 1:
Electrical connections are routed along the edges of the ceramic cavity in a planar configuration rather than requiring vertical wire-bonds through gaps, allowing connections to be made in the lateral dimension while maintaining close pixel spacing
Solution Approach 2:
The electrical connection function traditionally performed by wire-bonds through gaps is replicated using trace patterns on the ceramic cavity surface, eliminating the need for physical wire-bonding infrastructure and associated gaps
3Area of stationary object
If SiPM pixels are closely tiled without gaps, then tile fill factor and photon detection efficiency increase, but electrical interconnection between pixels becomes more difficult
Solution Approach 1:
The ceramic cavity acts as an intermediary substrate that provides integrated trace patterns for electrical connections between closely spaced pixel dies, mediating the electrical interconnection function while allowing pixels to be positioned at minimal spacing
Solution Approach 2:
Physical wire-bonding mechanisms are replaced with printed trace patterns on the ceramic cavity, substituting a mechanical connection system with an electrical field-based connection system that requires no physical gaps
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 more compact SiPM array with increased tile fill factor and photon detection efficiency, simplifying wire-bonding processes and enhancing detection capabilities.
Implementation Method 1
an electrical interconnection electrically isolated from the plurality of optical cells, the electrical interconnection arranged to provide electrical communication between two separate conducting terminals external to the pixel
Data Source
AI summary
According to embodiments of the present invention, a pixel arrangement is provided. The pixel arrangement includes a plurality of pixels arranged adjacent to each other; and a substrate configured to receive the plurality of pixels, wherein each pixel of the plurality of pixels comprises a plurality of optical cells electrically coupled to each other; and an electrical interconnection electrically isolated from the plurality of optical cells, the electrical interconnection arranged to provide electrical communication between two separate conducting terminals external to the pixel.