Semiconductor device and manufacturing method thereof

Abstract

A memory cell of a nonvolatile memory and a capacitive element are formed over the same semiconductor substrate. The memory cell includes a control gate electrode formed over the semiconductor substrate via a first insulating film, a memory gate electrode formed adjacent to the control gate electrode over the semiconductor substrate via a second insulating film, and the second insulating film having therein a charge storing portion. The capacitive element includes a lower electrode formed of the same layer of a silicon film as the control gate electrode, a capacity insulating film formed of the same insulating film as the second insulating film, and an upper electrode formed of the same layer of a silicon film as the memory gate electrode. The concentration of impurities of the upper electrode is higher than that of the memory gate electrode.

1 . A semiconductor device, comprising a memory cell of a nonvolatile memory, and a capacitive element which are formed over a semiconductor substrate, said memory cell comprising:
 a first gate electrode formed over the semiconductor substrate and comprised of silicon;   a second gate electrode arranged over the semiconductor substrate, formed adjacent to the first gate electrode, and comprised of silicon;   a first insulating film formed between the first gate electrode and the semiconductor substrate; and   a second insulating film formed between the second gate electrode and the semiconductor substrate and between the first gate electrode and the second gate electrode, said second insulating film having therein a charge storing portion,   said capacitive element comprising:   a first electrode formed over the semiconductor substrate and comprised of silicon; and   a second electrode formed over the first electrode via a capacity insulating film and comprised of silicon,   wherein a concentration of impurities of the second electrode is higher than that of impurities of the second gate electrode.   
     
     
         2 - 21 . (canceled)