Fabrication and Test of Pixelated CZT Detectors with Different Pixel Pitches and Thicknesses

TL;DR

This paper reports on the fabrication and testing of pixelated CZT detectors with varying pixel pitches and thicknesses, using a specialized readout system, to evaluate their spectral resolution and charge transport properties.

Contribution

It introduces a new readout system for pixelated CZT detectors and compares detectors made with different crystal growth methods and geometries.

Findings

Energy spectral resolution varies with pixel pitch and thickness.

Electron mobility-lifetime products depend on detector fabrication methods.

Detectors demonstrate high homogeneity and promising performance.

Abstract

The main methods grown Cadmium Zinc Telluride (CZT) crystals with high yield and excellent homogeneity are Modified Horizontal Bridgman (MHB) and High Pressure Bridgman (HPB) processes, respectively. In this contribution, the readout system based on two 32-channel NCI-ASICs for pixellated CZT detector arrays has been developed and tested. The CZT detectors supplied by Orbotech (MHB) and eV products (HPB) are tested by NCI-ASIC readout system. The CZT detectors have an array of 8x8 or 11x11 pixel anodes fabricated on the anode surface with the area up to 2 cm x2 cm and the thickness of CZT detectors ranges from 0.5 cm to 1 cm. Energy spectra resolution and electron mobility-lifetime products of 8x8 pixels CZT detector with different thicknesses have been investigated.