| 摘要 |
PROBLEM TO BE SOLVED: To make the entire surface of an element of an elevated source/drain structure a planar surface by stepwise forming second-conductivity-type elevated source/drain regions on a substrate and by forming an interlayer insulating film between a floating gate and a control gate buried in a recessed part of the floating gate and covered by the floating gate. SOLUTION: Elevated source/drain regions 33, 34 which are separated from a channel region 30 are formed stepwise on a substrate. A floating gate insulating film 35 is formed on the surface of the elevated source/regions 33, 34 and on the surface of a substrate 31 corresponding to a channel region, and a floating gate 37 having a recessed part in the center thereof is formed only on the floating gate insulating film 35 in the channel region. Then, an interlayer insulating film 38 is formed on the entire surface of the substrate 31 and a control gate 39 is formed only on the inside surface of the interlayer insulating film 38, such that it completely buries the recessed part. |
