Small field output correction factors should be applied when performing small field measurements. The small magnitude of these factors increases with decreasing field size. Additionally, the detector to detector variation of the microSilicon is almost negligible, which provides a sound basis for reliable small field correction factors. The new detector shows only a small loss of response over accumulated dose. The new design results in a very small water equivalent window thickness. This has positive effects on the output factors, the small field correction factors and the location of the effective point of measurement, which is now closer to the detector surface. Additionally, the profiles scanned by the micoSilicon are very close to a theoretical true profile.