A semiconductor device has a first region and a second region formed on a surface of a substrate. Plural first conductors and second conductors are formed in the first and second regions respectively. A first semiconductor region and a second semiconductor region are formed between adjacent first conductors. The second semiconductor region is in the first semiconductor region and has a conductivity type opposite to that of the first semiconductor. A third semiconductor region is formed between adjacent second conductors. The third semiconductor region has the same conductivity type as the second semiconductor region and is lower in density than the second semiconductor region. The third semiconductor region has a metal contact region for contact with a metal, which is electrically connected to the second semiconductor region. A center-to-center distance between adjacent first conductors is smaller than that between adjacent second conductors.