Semiconductor memory with voids for suppressing crystal defects

摘要

A trench isolating oxide film is formed in a groove formed at a silicon substrate. Floating gate electrodes and control gate electrodes are formed on trench isolating oxide film. An opening exposing the surface of silicon substrate is formed in a region located between the floating gate electrodes and others. The control gate electrodes are covered with a BPTEOS film filling opening. A void is formed within opening filled with BPTEOS film. The void suppresses occurrence of crystal defects in the silicon substrate, and the semiconductor device ensuring high reliability and high yield is obtained.