A first dielectric is formed over a semiconductor layer, a first gate layer over the first dielectric, a second dielectric over the first gate layer, and a third dielectric over the second dielectric. An etch is performed to form a first sidewall of the first gate layer. A second etch is performed to remove portions of the first dielectric between the semiconductor layer and the first gate layer to expose a bottom corner of the first gate layer and to remove portions of the second dielectric between the first gate layer and the third dielectric layer to expose a top corner of the first gate layer. An oxide is grown on the first sidewall and around the top and bottom corners to round the corners. The oxide is then removed. A charge storage layer and second gate layer is formed over the third dielectric layer and overlapping the first sidewall.