CZT Semiconductor Detector with Lithium Fluoride Trenches
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current radiation detection methods for neutrons and gamma rays are either expensive due to the difficulty in growing scintillator crystals like CLYC or suffer from low sensitivity and inability to distinguish between neutron and gamma-ray events in cadmium-zinc-telluride (CZT) detectors.
Innovation Solution
A compact, inexpensive semiconductor chip detector with a layer of cadmium-zinc-telluride (CZT) and trenches filled with lithium fluoride, utilizing an anode and cathode with a processor to differentiate between neutron and gamma-ray events based on signal magnitude and transit time, allowing for simultaneous detection and differentiation of both types of radiation at room temperature with low power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If CLYC scintillator crystals are used for neutron and gamma-ray detection, then detection sensitivity is improved, but manufacturing cost and difficulty increase significantly
Solution Approach 1:
The patent uses a composite structure combining CZT semiconductor material with a neutron-converting layer containing lithium-6 enriched material. This composite approach enables the detector to achieve both gamma-ray detection capability (through CZT) and neutron detection capability (through lithium-6 conversion to tritons) without requiring difficult-to-grow CLYC crystals
Solution Approach 2:
The patent replaces expensive, difficult-to-manufacture CLYC scintillator crystals with a more inexpensive and easier to manufacture CZT-based semiconductor detector structure, achieving comparable or superior performance at lower cost
2Adaptability or versatility
If cadmium-zinc-telluride (CZT) detectors are used for gamma-ray detection, then gamma-ray detection capability is achieved, but neutron detection sensitivity remains low and differentiation between neutron and gamma-ray events is difficult
Solution Approach 1:
The patent segments the detector into distinct functional regions: a gamma-ray sensitive CZT semiconductor region and a neutron-converting layer containing lithium-6 enriched material. This segmentation allows each region to optimize its specific function while working together for dual radiation detection
Solution Approach 2:
The patent introduces a lithium-6 enriched neutron-converting layer as an intermediary between incident neutrons and the CZT detector. This intermediary converts neutrons to tritons through nuclear reaction, which then generate detectable signals in the CZT, thereby enabling sensitive neutron detection
3Device complexity
If a single detector is used for both neutron and gamma-ray detection, then device complexity is reduced, but the ability to distinguish between neutron and gamma-ray events deteriorates
Solution Approach 1:
The patent applies local quality by creating regions with different properties within the single detector: the CZT region responds to both gamma rays and charged particles, while the lithium-6 enriched region specifically converts neutrons to tritons. The different signal characteristics from these regions enable event differentiation
Solution Approach 2:
The patent uses signal characteristic differentiation analogous to color changes - neutron events produce distinct signal signatures (different pulse shapes, amplitudes, or timing characteristics) compared to gamma-ray events, allowing the processor to distinguish between the two radiation types
4Measurement precision
If advanced scintillator crystal detectors are used, then detection performance is improved, but power consumption and operating temperature requirements increase
Solution Approach 1:
The patent changes the operating parameters by using CZT semiconductor material that operates effectively at room temperature, eliminating the need for cryogenic cooling systems required by many high-performance scintillator detectors. This reduces power consumption and simplifies the overall system
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 enables sensitive, cost-effective detection and differentiation of neutrons and gamma rays in a single semiconductor chip, operating at room temperature with minimal power requirements, improving upon existing technologies by enhancing sensitivity and reducing costs.
Implementation Method 1
the semiconductor material suitable for capturing gamma-ray events
Implementation Method 2
A CLYC scintillator crystal also can be used to capture neutrons through a nuclear reaction with lithium (Li) atoms in the crystal
Implementation Method 3
Like other scintillators, a CLYC crystal produces a flash of light when capturing a gamma ray
Implementation Method 4
applying an electric field across the semiconductor material
Data Source
AI summary
A method for detecting both gamma-ray events and neutron events with a common detector, where the detector includes a layer of semiconductor material bounded by electrodes, and the electrodes include an anode on one side of the semiconductor material and a cathode on the other side of the semiconductor material, includes the following steps: (a) monitoring the electrical signal at each of the anode and the cathode; and (b) comparing the magnitude of the signals at the anode and the cathode, and the transit time difference between the start of the anode signal and the time when the anode signal reaches a maximum, relatively constant value. In the comparing step, predetermined criteria are used to differentiate between gamma-ray events and neutron events.