Semiconductor device capable of increasing reliability

Claim 1

A semiconductor device comprising: a semiconductor substrate having a principal surface; a first insulator layer overlying said principal surface and having a first upper insulator surface; a plurality of accumulation electrode layers overlying said first upper insulator surface with spaces being formed between adjacent ones of said accumulation electrode layers, said spaces exposing part surfaces of said first upper insulator surface, said accumulation electrode layers having upper electrode surfaces and side electrode surfaces; a plurality of second insulator layers overlying said part surfaces and being in contact with said side electrode surfaces, said second insulator layers having second upper insulator surfaces, each of said second insulator layers having a primary dielectric constant; a dielectric layer overlying said upper electrode surfaces and said second upper insulator surfaces and having an upper dielectric surface and a secondary dielectric constant which is higher than said primary dielectric constant; and an opposed electrode layer overlying said upper dielectric surface; and wherein said primary dielectric constant is from 3 to 30, said second dielectric constant being from 200 to 2,000.