Fabrication processes for semiconductor non-volatile memory device

A method for fabricating a semiconductor non-volatile memory device comprising:

• forming a first layer on a silicon substrate that is selectively removable with respect to the silicon substrate;
• forming an isolation region surrounding the first layer;
• forming a second layer on the first layer comprising silicon and having a higher dopant concentration than the silicon substrate;
• forming a gate oxide layer on the second layer;
• forming a control gate on the gate oxide layer having two opposed ends in contact with the isolation region;
• etching the control gate, the gate oxide layer, the second layer, the first layer, and an upper part of the silicon substrate along two opposed sidewalls to form cavities;
• selectively etching the first layer to form a tunnel between the second layer and the silicon substrate;
• insulating the second layer by forming an insulating layer on the sidewalls of the second layer and in at least part of the tunnel;
• filling the cavities with silicon;
• and
• forming source and drain regions in the filled cavities on each side of the second etched layer to define a floating gate.