Development of a double-sided LGAD prototype from single-sided sensors: design, characterization, and proof of principle

This work presents the development and experimental validation of a novel thin (active layer thickness of 85 μm) double-sided strip Low-Gain Avalanche Detector (LGAD) prototype. We demonstrate a post-fabrication segmentation process where a standard single-sided LGAD sensor is micromachined to enable dual-sided signal extraction. Characterization using a dedicated front-end electronics system confirms strong spatial and temporal correlations between the junction and ohmic sides. The results validate that this architecture preserves the excellent timing performance of LGADs while providing a scalable solution for high-precision tracking in material-sensitive applications. By applying this procedure in conjunction with additional sensor thinning, a total sensor thickness below 50 μm can be achieved. To our knowledge, this represents the first implementation of a thin double-sided LGAD.