| 摘要 |
PROBLEM TO BE SOLVED: To improve resistance to dielectric breakdown while large capacitance is maintained by using a silicon nitride film of high permitivity, by constituting a capacitor dielectric film in the parts which are in contact with an upper and a lower electrodes, of silicon nitride films of high density as compared with the part which is not in contact with the electrodes. SOLUTION: A capacitor dielectric film 3 is constituted of a silicon nitride film. High density silicon nitride films 3A and 3C which are in contact with the lower electrode 2 and the upper electrode 5 have high density as compared with a low stress silicon nitride film 3B which is not in contact with the electrodes. The dielectric film which is in contact with the electrodes 2, 3 and has possibility of dielectric breakdown due to pin holes does not reach dielectric breakdown, because the high density silicon nitride film is used. Except the silicon nitride film which is in contact with the electrodes 2, 3, the silicon nitride film of low stress is used, so that deterioration of reliability due to film stress becomes hard to be generated. |
