Nonvolatile EPROM, EEPROM of flash-EEPROM memory with tunnel oxide protection

An intermediate structure for forming a memory with tunnel oxide protection, comprising:

• a substrate of semiconductor material;
• thick oxide regions delimiting active areas of said memory;
• thin oxide portions overlying said active areas of the memory;
• regions of semiconductor material overlying said thin oxide portions;
• portions of dielectric material overlying said regions of semiconductor material;
• and
• an unpatterned layer of semiconductor material covering at least the portions of dielectric material;
• wherein the structure further comprises conductive paths connecting said unpatterned layer to said substrate.

A nonvolatile memory, comprising:

• at least one memory cell, having;
• a substrate of semiconductor material;
• a control gate region on said substrate capable of reaching an operating potential;
• a floating gate region on said substrate;
• a tunnel oxide layer separating said floating gate region from said substrate;
• wherein said tunnel oxide layer will be damaged if the floating gate region reaches a breakdown voltage;
• and
• means for preventing the floating gate region from reaching the breakdown voltage.