Novel method to planarize semiconductor surface

摘要

A method to planarize a semiconductor surface using a Fence Creation and Elimination (FCE) process is described. Shallow recesses on a semiconductor surface are filled with a filling material. The filling material is deposited on the semiconductor surface to a thickness approximately equal to the depth of the shallow recesses. A selectively etchable material is formed on the filling material. A reverse mask (RM) is used to pattern the selectively etchable material to form segments of the selectively etchable material equal to the pattern of the shallow recesses and aligned to the shallow recesses. Exposed filling material is removed followed by the removal of the segments of the selectively etchable material. The remaining filling material in the shallow recesses forms fences which extend above the surface of the semiconductor. The fences are removed resulting in a planar semiconductor surface.