Semiconductor devices with overlapping gate electrodes and methods of fabricating the same

摘要

A semiconductor device, such as a flash memory device, includes an isolation region provided in a trench in a substrate and having a recess therein. The device also includes a tunnel oxide layer pattern on the substrate adjacent the isolation region, and a first gate electrode provided on the tunnel oxide layer pattern and extending onto a portion of the isolation region adjacent the recess. The device further includes a dielectric layer provided on the first gate electrode and a second gate electrode provided on the dielectric layer and extending into the recess in the isolation region. The first gate electrode may include a conductive layer pattern provided on the tunnel oxide layer pattern and a conductive spacer provided on a sidewall of the first conductive layer pattern adjacent the recess in the isolation region.