Infineon Technologies Ag

Bernd G&ouml;bel

Martin Gutsche

Alfred Kersch

Werner Steinh&ouml;gl

Buried straps are produced on one side in deep trench structures. A PVD process is used to deposit masking material in the recess inclined at an angle. As a result, a masking wedge is produced on the buried strap, on one side in the base region of the recess. The masking wedge serves as a mask during a subsequent anisotropic etching step, which is carried out selectively with respect to the masking wedge, for removing the buried strap on one side.

Method and installation for fabricating one-sided buried straps

A depression is produced in a substrate for a capacitor of a memory cell of the DRAM cell configuration. An insulation and a storage node of the capacitor are produced in the depression. A spacer made of silicon is produced above the storage node. A first part of the spacer is doped by inclined implantation. The spacer is patterned by utilizing the different doping of the first part of the spacer. With the aid of the patterned spacer as a mask, the storage node and the insulation are altered in such a way that the storage node directly adjoins the substrate only in a limited patch of a sidewall of the depression and is otherwise isolated from the substrate by the insulation.

Growing community of inventors

Dresden, Germany

Bernd Göbel

Growing community of inventors

Dresden, Germany

Bernd G&ouml;bel

Bernd Göbel