| 摘要 |
Provided is a "castled" active area mask. A castled active area mask is one which has been lengthened to extend beyond its intended intersection with a tunnel dielectric to form the tunnel window of an EEPROM cell, and has also been widened in at least a portion of the extension. For example, in one preferred embodiment, a castled extension may have a "T" shape. The castled active area generated by such a mask provides a buffer to absorb field oxide encroachment before it reaches the EEPROM cell's TD window. A mask in accordance with the present invention may be used to fabricate EEPROM cells which are not subject to TD window size variations due to field oxide encroachment, and EEPROM cell arrays of increased density.
|
