US Patent 7755168 Semiconductor device provided with floating electrode

A semiconductor device has a first conductivity-type first semiconductor region, a second conductivity-type second semiconductor region and a second conductivity-type third semiconductor region both located on or above the first semiconductor region, a second conductivity-type fourth semiconductor region between the second semiconductor region and the third semiconductor region, and a first conductivity-type fifth semiconductor region between the third semiconductor region and the fourth semiconductor region. The fourth semiconductor region and the fifth semiconductor region are electrically connected by a conductive member. A distance between the fourth semiconductor region and the third semiconductor region is larger than a width of the fourth semiconductor region.