Methods of Manufacturing Flash Memory Devices by Selective Removal of Nitrogen Atoms

A method of manufacturing a flash memory device, the method comprising:

• forming a dielectric layer on an active region of a substrate;
• forming a floating gate that includes a polysilicon on the dielectric layer;
• forming an isolation layer that includes an oxide in an isolation region of the substrate;
• forming a nitride layer comprising a first nitride layer portion that is formed on an exposed surface of the floating gate and a second nitride layer portion that is formed on an exposed surface of the isolation layer;
• and
• selectively removing nitrogen atoms from the second nitride layer portion of the nitride layer.

A method of manufacturing a flash memory device, the method comprising:

• forming an electrode pattern that includes a polysilicon on a substrate;
• forming an oxide layer around the electrode pattern;
• forming a nitride layer comprising a first nitride layer portion that is formed on an exposed surface of the electrode pattern and a second nitride layer portion that is formed on an exposed surface of the oxide layer, by exposing the substrate to a nitridation atmosphere;
• performing a thermal treatment process on the nitride layer;
• and
• selectively removing nitrogen atoms from the second nitride layer portion.