Low voltage Fowler-Nordheim flash EEPROM memory array utilizing single level poly cells

A Flash EEPROM memory having a memory array of EEPROM memory cells arranged in rows and columns on the face of a semiconductor substrate of a first conductivity type material and operable to be programmed with positive and negative voltages, the memory cells each comprising:

• a channel region of first conductivity type material formed in the face of the substrate within an active moat region;
• a source region of second conductivity type material adjacent to the first conductivity type material and disposed on one side of said channel region;
• a drain region of said second conductivity material disposed in said moat region on said opposite side of said channel region from said source region;
• a floating gate overlying a portion of said channel region;
• a tunnel oxide layer disposed between said floating gate and said channel region to allow for Fowler-Nordheim electron tunneling therethrough;
• a control gate comprising a semiconductor region of the second conductivity type material formed on the face of the substrate and separated from said moat region and coupling electrically directly to said floating gat;
• a coupling structure for coupling said control gate to said floating gate to form a floating gate transistor;
• and
• an isolation structure for allowing said control gate to have positive and negative voltages disposed thereon without substantial conduction from the control gate to the substrate, wherein said isolation structure comprises
• a first isolation tank of first conductivity type material disposed about the memory cell and operable to be biased at a voltage potential that will prevent forward biasing of the semiconductor junction between said first isolation tank and said doped control gate region, and
• a second conductivity type material disposed about said first tank and disposed at a voltage that will prevent forward biasing of the semiconductor junction between said first isolation tank and said second isolation tank.