Investigating the performance of the novel microSilicon diode detector for high-resolution dosimetry in radiotherapy: Flat and FFF beams across multiple energies

Accurate dosimetry in small photon fields is challenged by detector size and electronic disequilibrium. We compared a microSilicon diode, a microDiamond detector and Gafchromic EBT3 film for 6 and 10 MV beams in flattened and flattening-filter-free modes (FFF). Film served as high-spatial-resolution comparator (absolute dose referenced to ion chamber). Film calibration (0–360.9 cGy) was reproducible within ≤2 % with cubic fits (R 2 ≈ 1). Percentage-depth-dose curves from both diodes agreed within 2.1 % across field sizes. Lateral profiles showed sharper penumbrae with microSilicon, with deviations <1.5 % against film, cross-plane differences reached ∼5 % for 5 × 5 mm 2 but were negligible for ≥30 × 30 mm 2 . Full-width-at-half-maximum analysis indicated slightly broader penumbrae at 10 MV (∼+0.1 mm) and narrower in-plane penumbrae for FFF beams. Output factors ranged from ∼0.70 (5 × 5 mm 2 ) to 1.00 (40 × 40 mm 2 ). Mainly, microSilicon agreed more closely with film than microDiamond in the smallest fields.