We present a novel geometry of scintillator tiles developed for fiberless
coupling to silicon photomultipliers (SiPMs) for applications in highly
granular calorimeters. A high degree of uniformity of the tile response over
the full active area was achieved by a drilled slit at the coupling position of
the photon sensor with 2 mm, 4 mm and 5.5 mm in height, width and depth.
Detailed measurements of the response to penetrating electrons were performed
for tiles with a lateral size of 3 x 3 cm^2 and thicknesses of 5 mm and 3 mm.Comment: 6 pages, 8 figures, accepted by NIM