An Overhanging Absorber for TES X-Ray Focal Planes

In order to improve pixel count and collecting area, future transition edge sensor X-ray focal planes require pixels with both a higher coverage of the active area and compatibility with in-focal-plane multiplexing. To achieve these improvements, we have developed a pixel with an “overhanging” geometry that allows us room for multiplexing elements underneath the absorber simultaneously with the possibility of near full coverage of the focal plane. We have fabricated and tested such a pixel. We have demonstrated a spectroscopic resolution of 3.2 eV full-width at half-maximum at 5.9 keV, thereby showing that it is suitable for applications in the near future.