Abstract: A method for fabricating a semiconductor memory device is described. An insulating layer is disposed on a semiconductor substrate. A matrix of semiconductor memory elements is disposed in the substrate. The semiconductor memory elements include a plurality of contact holes formed in the insulating layer. One contact hole is formed in the insulating layer for each of the semiconductor memory elements. A bit definition region is disposed in the semiconductor substrate underneath each of the contact holes. A contact plug is disposed in each of the contact holes and is in electrical contact with the bit definition region. The bit definition region is configured such that a contact resistance between the semiconductor substrate and the contact plug defines a bit to be stored in the semiconductor memory elements, An evaluation circuit is connected to and evaluates the contact resistance of the semiconductor memory elements.

Abstract: The invention relates to a method for the planarization of a semiconductor structure comprising a substrate, in which several sub-structures (STI; AA; AA?; AA?;) are provided. said sub-structures (STI; AA; AA?; AA?,) having a first sub-structure (AA?) with planar regions (PS) and first trench regions (DT). A layer to be planarized is applied over the semiconductor structure, said layer having appropriate recesses above the first trench regions (DT) of the first sub-structure (AA?). The method comprises the following steps: pre-planarization of the layer to be planarized by an etching step, using a pre-planarization mask, then subsequent planarization of the layer to be planarized by a chemical-mechanical polishing step.

Abstract: The invention relates to a method for the planarization of a semiconductor structure comprising a substrate, in which several sub-structures (STI; AA; AA′; AA″;) are provided. said sub-structures (STI; AA; AA′; AA″,) having a first sub-structure (AA′) with planar regions (PS) and first trench regions (DT). A layer to be planarized is applied over the semiconductor structure, said layer having appropriate recesses above the first trench regions (DT) of the first sub-structure (AA′). The method comprises the following steps: pre-planarization of the layer to be planarized by an etching step, using a pre-planarization mask, then subsequent planarization of the layer to be planarized by a chemical-mechanical polishing step.

Abstract: The memory cell configuration has a large number of memory cells provided in a semiconductor substrate and having bit-line trenches which extend in parallel in the longitudinal direction in the main face of the semiconductor substrate, at the bottoms of which in each case a first conductive region is provided, at the peaks of which in each case a second conductive region of the same conduction type as the first conductive region is provided, and in the walls of which in each case an intermediately located channel region is 0 provided; and having word lines which extend in the transverse direction along the main face of the semiconductor substrate, through specific bit-line trenches, to activate transistors provided there. An additional dopant is introduced into the trench walls of the bit-line trenches which are located between the word lines, in order to increase the corresponding transistor turn-on voltage there to suppress leakage currents.