Abstract
Over the past few decades, considerable effort has been invested in developing a range of compound semiconductors for use as photon and charged particle detectors. The key material requirements for the compound semiconductors are high effective atomic number to provide sufficient stopping power, wide enough bandgap to ensure operation at room temperature, and excellent material charge carrier transport properties and uniform spatial and spectral response.
Cadmium zinc telluride (CdZnTe) is a material that has attracted considerable interest due to its potential in room temperature semiconductor detector applications. Its distinctive properties, including a high atomic number, wide bandgap, and high electron mobility, position it as an ideal detector material for a variety of applications. These applications span across diverse fields such as medical imaging, safety and homeland security, as well as scientific space instrumentation.
Although CdZnTe possesses several desirable material properties for use as a room temperature semiconductor detector, it also exhibits certain drawbacks. Specifically, the poor charge transport properties of holes which are significantly lower than those of electrons within CdZnTe crystals. This discrepancy can result in inefficient charge collection and thus degrade the CdZnTe detector performance.
To address the challenge of inefficient hole collection in CdZnTe detectors, a potential solution involves modifying the electrode design. By implementing geometrically weighted contacts, the electrode geometry can be tailored to primarily respond to the drift of electrons, thereby enhancing the charge collection efficiency and consequently improving overall detector performance.
At the Danish Space Research Institute (DSRI), today DTU Space, the 3D CdZnTe drift strip detector technology has been developed alongside the associated drift strip method for pulse shape analysis. The developed detector technology displays excellent position resolution in three dimensions (<0.5 mm) and energy resolution (<1%) at 661.6 keV, achieved through pulse shape signal processing. Signal formation on each electrode readout employs bipolar charge-sensitive preamplifiers. The output is sampled using high-speed digitizers, providing full pulse shapes generated by each interaction in the detector.
In this chapter, we review the 3D CdZnTe drift strip detector technology from its inception in the late 1990s, focusing on major breakthroughs in development up to the present day. We present noteworthy results, covering the initial proof of concept up to today, and discuss notable applications for the detector. Looking forward, we outline future research directions within this technology.
Cadmium zinc telluride (CdZnTe) is a material that has attracted considerable interest due to its potential in room temperature semiconductor detector applications. Its distinctive properties, including a high atomic number, wide bandgap, and high electron mobility, position it as an ideal detector material for a variety of applications. These applications span across diverse fields such as medical imaging, safety and homeland security, as well as scientific space instrumentation.
Although CdZnTe possesses several desirable material properties for use as a room temperature semiconductor detector, it also exhibits certain drawbacks. Specifically, the poor charge transport properties of holes which are significantly lower than those of electrons within CdZnTe crystals. This discrepancy can result in inefficient charge collection and thus degrade the CdZnTe detector performance.
To address the challenge of inefficient hole collection in CdZnTe detectors, a potential solution involves modifying the electrode design. By implementing geometrically weighted contacts, the electrode geometry can be tailored to primarily respond to the drift of electrons, thereby enhancing the charge collection efficiency and consequently improving overall detector performance.
At the Danish Space Research Institute (DSRI), today DTU Space, the 3D CdZnTe drift strip detector technology has been developed alongside the associated drift strip method for pulse shape analysis. The developed detector technology displays excellent position resolution in three dimensions (<0.5 mm) and energy resolution (<1%) at 661.6 keV, achieved through pulse shape signal processing. Signal formation on each electrode readout employs bipolar charge-sensitive preamplifiers. The output is sampled using high-speed digitizers, providing full pulse shapes generated by each interaction in the detector.
In this chapter, we review the 3D CdZnTe drift strip detector technology from its inception in the late 1990s, focusing on major breakthroughs in development up to the present day. We present noteworthy results, covering the initial proof of concept up to today, and discuss notable applications for the detector. Looking forward, we outline future research directions within this technology.
| Original language | English |
|---|---|
| Title of host publication | Advancements in CdZnTe Detectors with the Drift Strip Method |
| Editors | K. Iniewski |
| Publisher | Springer |
| Publication date | 2024 |
| Pages | 51-70 |
| ISBN (Print) | 978-3-031-64520-4 |
| ISBN (Electronic) | 978-3-031-64521-1 |
| DOIs | |
| Publication status | Published - 2024 |