Suspended Thermal Detector Electrode Layout for Lower 1/f Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing thermal detectors face challenges in optimizing the electrical resistance and 1/f noise of the thermistor layer, which affects performance metrics such as NETD and NEP, due to limitations in the design of the electrodes and thermistor layer configuration.
Innovation Solution
A thermal detector design featuring a first electrode in the form of a looped track along the periphery of the absorbing membrane and a second electrode with a central part and radial track, combined with a thermistor layer having peripheral and central contact zones, optimizes the electrical resistance while maintaining a sufficient biased volume to minimize 1/f noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the thermistor layer is made with a rectangular configuration and parallel electrode edges, then the biased volume is sufficient to avoid excessive 1/f noise, but the electrical resistance is not optimal due to the low width-to-length ratio
Solution Approach 1:
The patent applies curvature by transforming the straight electrode edges into serpentine (sinuous) shapes. This allows the electrodes to follow a curved path that increases the effective width dimension while maintaining the required length, thereby optimizing the width-to-length ratio and reducing electrical resistance without compromising the biased volume
2Manufacturing precision
If the electrode width is increased beyond the pixel dimension, then the electrical resistance would be optimized, but the pixel size constraints prevent this extension
Solution Approach 1:
The patent resolves this contradiction by transitioning from a one-dimensional straight line configuration to a two-dimensional serpentine path. The electrodes meander within the available pixel area, effectively utilizing the spatial dimension to increase the electrode width equivalent without expanding the overall pixel footprint
3Manufacturing precision
If the dimension L between electrode contact zones is reduced, then the electrical resistance improves, but the biased volume becomes too small causing excessive 1/f noise
Solution Approach 1:
The serpentine configuration allows the electrodes to approach each other more closely in certain regions while maintaining the overall biased volume through the curved path. This effectively reduces the electrical resistance by decreasing the separation distance L in key regions while the cumulative path length maintains sufficient biased volume
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 improved electrode and thermistor layer configuration enhances the thermal detector's performance by optimizing electrical resistance and reducing 1/f noise, leading to better NETD and NEP parameters.
Implementation Method 1
comprising an absorber of the electromagnetic radiation to be detected
Implementation Method 2
The thermistor layer 53 is made of a material having an electrical resistance which varies with its own heating
Implementation Method 3
the absorbing membrane is suspended above a readout substrate by anchoring pillars, and is thermally insulated from it by holding arms
Data Source
AI summary
A thermal detector comprising an absorbing membrane suspended above a readout substrate, which comprises a thermistor layer resting on two electrodes. The first electrode is a looped track, and the second electrode comprises a central part and a radial track. Furthermore, the thermistor layer has a peripheral contact zone in contact with the first electrode and a central contact zone in contact with the central part; the thermistor layer being electrically insulated from the radial track.