| 摘要 |
PURPOSE:To enhance insulation resistance by clad-forming thickly a material which becomes a dielectric film on the bottom of a charge accumulated electrode which is predictable to get thinner definitely latter. CONSTITUTION:On the surface of a semiconductor substrate 1 are formed a CVD oxide film 21, a CVD nitride film 22, and a CVD oxide film 23 one over, thereby forming a contact hole 3 which exposes the surface of the silicon substrate 1 from this surface. Inside and outside the hole is formed a charge accumulated electrode 5. Moreover, a first nitride film 4 is formed only on the bottom where a main nitride film 7 is formed in such a manner that it may cover the surface of the first nitride film 4 and the charge accumulated electrode 5. A counter electrode 8 is further formed in such a manner that it may come into contact with the main nitride film which covers the electrode 5. The first nitride film 7 is uniformly clad on the front surface and the bottom surface of the charge accumulated electrode 5 at a thickness of 60Angstrom on the top and at a thickness of 40Angstrom (maximum value) on the bottom of the first nitride film 4 based on a CVD process. In this manner, the nitride film can be formed at a satisfactory thickness, say, 80Angstrom (maximum value) even on the bottom of the charge accumulated electrode 5. |
