Nikon S620 has a
12.0MP 1/2.3-inch (6.08 x 4.56 mm ) sized CCD sensor . On the other hand, Sony TF1 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the S620 and TF1 sensor size comparison.
Nikon S620 and Sony TF1 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.