Microscale Gas Discharge Ion Detector for Atmospheric Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ion detectors, such as electron multipliers and Faraday cup detectors, are not suitable for compact, portable, and hand-held micro analyzers operating at atmospheric pressure due to requirements for low pressure and limited manufacturability at the wafer level, respectively, and lack high sensitivity for single charge detection.
Innovation Solution
A microscale gas discharge ion detector with a planarized structure featuring a flat anode grid and cathode, utilizing a high electric field to initiate avalanching discharge and surface quenching in micro channels for high sensitivity and count rate, allowing operation at atmospheric pressure with a dynamic range similar to electron multiplier tubes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If electron multipliers are used for high sensitivity ion detection, then single charge detection sensitivity is achieved, but operation requires very low pressure (below millitorr level) which is incompatible with atmospheric pressure operation
Solution Approach 1:
The invention changes the operating parameters by using a microscale gap (10-500 microns) between electrodes filled with gas at atmospheric pressure, replacing the vacuum requirement of electron multipliers with a gas-filled microgap configuration that enables avalanche discharge at ambient pressure while maintaining high sensitivity
Solution Approach 2:
The invention replaces the electron multiplication mechanism (which requires vacuum) with a gas discharge avalanche mechanism in a microscale gap, substituting one physical phenomenon for another that is compatible with atmospheric pressure operation while achieving similar amplification effects
2Adaptability or versatility
If Faraday cup detectors are used for atmospheric pressure operation, then operation at or near atmospheric pressure is achieved, but intrinsic amplification of multiplier is not provided resulting in limited usefulness in high-sensitivity applications
Solution Approach 1:
The invention introduces intrinsic amplification by operating in the avalanche discharge regime where a small number of initial ions trigger a cascade of ionizations in the gas-filled microgap, providing multiplier-like amplification factors while maintaining atmospheric pressure operation capability
Solution Approach 2:
The invention segments the detection process into ionization, avalanche multiplication, and collection stages within the microscale gap structure, enabling both atmospheric pressure operation and high sensitivity detection by separating these functions spatially and temporally
3Measurement precision
If conventional ion detectors are designed for high sensitivity detection, then single charge detection is achieved, but the devices are not readily manufacturable at the wafer level to achieve compactness and low cost
Solution Approach 1:
The invention extracts the essential detection function from complex vacuum tube structures and implements it in a simplified planar microscale configuration that can be fabricated using standard semiconductor processing techniques, enabling wafer-level manufacturing while maintaining high sensitivity
Solution Approach 2:
The invention transitions from three-dimensional tube structures to a two-dimensional planar configuration with microscale gaps, enabling integration with other planar devices and wafer-level fabrication while preserving the avalanche discharge mechanism for high sensitivity detection
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 microscale gas discharge ion detector achieves high sensitivity and count rates at atmospheric pressure, enabling compact, cost-effective, and integratable ion detection suitable for portable gas analyzers and micro ion trap mass spectrometers, with a dynamic range of six orders of magnitude.
Implementation Method 1
utilizing a high electric field to initiate avalanching discharge
Implementation Method 2
utilizing a high electric field to initiate avalanching discharge
Implementation Method 3
surface quenching in micro channels for high sensitivity and count rate
Implementation Method 4
confined discharge and surface quenching in a micro channel
Data Source
AI summary
A microscale planar device for detecting particles under high pressure with high sensitivity. The device may have an anode and cathode with an insulator situated between them. The insulator may have a number of holes, cavities or channels between the anode and cathode. There may be conductive rings at the perimeters of openings of the channels on the anode side of the insulator. These rings may be a part of the anode. An ion may be attracted into one of the channels where it interacts with a gas to result in an avalanche breakdown. The breakdown may be detected by instrumentation connected to the anode and cathode. The lateral and/or longitudinal dimensions of the channels may be such that the device may operate as a detector with ambient air as a gas under its pressure of about one atmosphere.