A highly pixelated CdZnTe detector based on \textit{Topmetal-${II}^-$} sensor

TL;DR

This paper presents a novel high-resolution radiation detector combining a low-noise CMOS pixel sensor with CdZnTe semiconductor material, demonstrating promising results for X-ray imaging applications.

Contribution

It introduces a new detector design integrating Topmetal-${II}^-$ sensor with CdZnTe, achieving high spatial resolution and effective charge collection at low bias voltage.

Findings

Clear alpha particle images with good spatial resolution

Measured electron diffusion coefficient and charge efficiency

Potential for improved X-ray imaging applications

Abstract

\textit{Topmetal-${II}^-$} is a low noise CMOS pixel direct charge sensor with a pitch of 83$\mu m$. CdZnTe is an excellent semiconductor material for radiation detection. The combination of CdZnTe and the sensor makes it possible to build a detector with high spatial resolution. In our experiments, an epoxy adhesive is used as the conductive medium to connect the sensor and Cadmium Zinc Telluride (CdZnTe). The diffusion coefficient and charge efficiency of electrons are measured at a low bias voltage of -2 Volts, and the image of a single alpha is clear with a reasonable spatial resolution. The detector of such structure has the potential to be applied in X-ray imaging systems with a further improvements of the sensor.