High-rate, high-resolution single photon X-ray imaging: Medipix4, a large 4-side buttable pixel readout chip with high granularity and spectroscopic capabilities

TL;DR

The Medipix4 chip advances high-resolution, high-rate spectroscopic X-ray imaging with a large, tilable pixel array, enabling large-area detectors with minimal dead zones and improved photon energy discrimination.

Contribution

This paper introduces the Medipix4 chip with a novel large, 4-side buttable pixel array and advanced readout architecture for high-rate spectroscopic X-ray imaging.

Findings

Successful electrical measurements demonstrating chip capabilities

High granularity and spectroscopic performance confirmed

Minimal dead area due to 4-side tiling design

Abstract

The Medipix4 chip is the latest member in the Medipix/Timepix family of hybrid pixel detector chips aimed at high-rate spectroscopic X-ray imaging using high-Z materials. It can be tiled on all 4 sides making it ideal for constructing large-area detectors with minimal dead area. The chip is designed to read out a sensor of 320 x 320 pixels with dimensions of 75 {\mu}m x 75 {\mu}m or 160 x 160 pixels with dimensions of 150 {\mu}m x 150 {\mu}m. The readout architecture features energy binning of the single photons, which includes charge sharing correction for hits with energy spread over adjacent pixels. This paper presents the specifications, architecture, and circuit implementation of the chip, along with the first electrical measurements.