摘要 |
A method for forming a recess. The method includes providing a substrate with two protrusions having a first side wall and a second side wall opposite to the first side wall disposed above the substrate, conformally forming a mask layer on the substrate and the protrusions, tilt implanting the mask layer with a first angle using a first implanting mask adjacent to the first side wall of the protrusions, tilt implanting the mask layer with a second angle using a second implanting mask adjacent to the second side wall of the protrusions, removing implanted portions of the mask layer to form a patterned mask layer, and etching the substrate using the patterned mask layer, thereby forming a recess, wherein distances from the recess to the two protrusions, respectively, are different.
|