Semiconductor memory device and method of manufacturing the same

A semiconductor memory device comprising:

• a plurality of memory elements formed on a top surface of a semiconductor substrate;
• an interlayer insulating film buried between the adjacent memory elements;
• a protection film formed on sides of each of the memory elements and the top surface of the semiconductor substrate between the adjacent memory elements;
• and
• a contact formed in the interlayer insulating film,
• wherein the protection film includes:
• a first protection film formed on the sides of each of the memory elements and the top surface of the semiconductor substrate between the adjacent memory elements;
• and
• a second protection film formed on the first protection film, the second protection film being made of a boron nitride film.

A method of manufacturing a semiconductor memory device comprising:

• forming a plurality of memory elements on a top surface of a semiconductor substrate;
• forming a first protection film made of a silicon oxide film, a silicon nitride film, or a silicon oxynitride film on sides of each of the memory elements and the top surface of the semiconductor substrate between the adjacent memory elements;
• forming a second protection film made of a boron film or a boron nitride film on the first protection film;
• burying an interlayer insulating film between the adjacent memory elements;
• and
• forming a contact hole in the interlayer insulating film present between the adjacent memory elements by using an etching process.