Impurity ion segregation precluding layer, fabrication method thereof, isolation structure for semiconductor device using the impurity ion segregation precluding layer and fabricating method thereof

Granted: Jan 8, 2002 Filed: Nov 16, 1999

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.