Patent ID: 7838405
Filing Date: 2010-11-23
Classification: H01L

Abstract:
1. A method for manufacturing a semiconductor device having a bulb-type recessed channel comprising: forming a trench that defines an active region including a channel region that defines a sidewall and a junction region in a semiconductor substrate; forming an isolation layer that fills the trench, and forming a sidewall pattern that covers a sidewall of the channel region; forming a first trench defining a sidewall in the channel region by etching the semiconductor substrate, forming a barrier layer on the sidewall of the first trench; removing the sidewall pattern to form a bottom protrusion having exposed side surfaces spaced a predetermined distance from the isolation layer, forming a second, spherical trench from the bottom surface of the first trench using the barrier layer as an etch mask to form a bulb-type trench consisting of the first trench and the second trench; and forming a gate stack that fills the bulb-type trench and the bottom protrusion including the exposed side surfaces.