Patent ID: 8742549
Filing Date: 2014-06-03
Classification: H01L

Abstract:
1. A semiconductor structure, comprising: a substrate with at least a trench insulation structure therein, wherein the trench insulation structure comprises a top surface and a side surface above the substrate; a first patterned polysilicon layer disposed on the trench insulation structure and only covering the top surface above the substrate but not covering the side surface above the substrate; a second patterned polysilicon layer disposed above the first patterned polysilicon layer and the substrate, the second patterned polysilicon layer is disposed on sidewalls around the trench insulation structure, wherein the first patterned polysilicon layer and the second patterned polysilicon layer are patterned under a cross sectional view such that a part of the trench insulation structure is neither covered by the first patterned polysilicon layer nor the second patterned polysilicon layer; and a dielectric layer disposed between the first and second patterned polysilicon layers, wherein the dielectric layer is in direct contact with the top surface of the substrate around the trench insulation structure.