Method of forming thin layers and method of manufacturing a non-volatile memory device using the same

A method of manufacturing a non-volatile memory device, the method comprising:

• providing a semiconductor substrate having a source layer;
• forming a gate insulation layer on the semiconductor substrate;
• forming a silicon nitride layer having a buffer-treated upper surface on the gate insulation layer;
• forming a silicon oxide layer on the buffer-treated upper surface of the silicon nitride layer;
• and
• alternately forming additional silicon nitride layers and additional silicon oxide layers on the silicon oxide layer to form a stack structure,
• wherein the buffer-treated upper surface of the silicon nitride layer has a hardness higher than a hardness of the silicon nitride layer.

A method of forming thin layers, the method comprising:

• forming a first layer having a first lattice size;
• forming, on the first layer, a second layer having a second lattice size smaller than the first lattice size;
• buffer-treating an upper surface of the second layer to provide the upper surface of the second layer with a hardness higher than a hardness of other portions of the second layer;
• and
• forming a third layer having the first lattice size and a material same as the first layer, on the buffer-treated upper surface of the second layer.