Double-side pixelated X-ray detector based on metamorphic InGaAs/InAlAs quantum well

Due to the high atomic number, low band gap and high electron mobility of III-IV semiconductors, the use of metamorphic InGaAs/InAlAs quantum well-based devices was proposed for fast pixelated photon detectors. In this work, we are presenting a double side-segmented quantum well (QW) device, discussing its spatial resolution and analysing the crosstalk between pixels. The fabricated devices were tested with needle-shaped beams of synchrotron radiation with different energies and spot sizes. The position of the synchrotron radiation was estimated with a 1.3-μm precision. The charge spread in the material and related crosstalk function between pixels were extracted from the position estimation measurements of the photon beams. The results show that the cross-talk between pixels is actually responsible for the different resolutions obtained, regardless of the experimental conditions, pointing out the importance of the geometry of the fabricated devices. Furthermore, it has been observed that the QW pixelation is mandatory for hybrid detector technology.