Test structure for a single-sided buried strap DRAM memory cell array

1. A test structure for determining the electrical properties of memory cells, comprising:

a selection transistor and a storage capacitor, in a matrix-like cell array, where the selection transistors have an active region with a gate electrode, where the active region is conductively connected to a bit line and an internal electrode in the storage capacitor, and the gate electrode is conductively connected to a word line, where the active regions of the selection transistors are arranged in rows in a first direction, and the storage capacitors are arranged in rows in a second direction, which runs transversely with respect to the first direction, where the conductive connection between the active region of the selection transistor and the internal electrode in the storage capacitor in the memory cells on overlapping areas of the crossing rows of active regions and storage capacitors is respectively produced in a single edge region of the overlapping area, where the bit lines run in the first direction, making contact with the active regions of the selection transistors in the first direction, and the word lines run in the second direction, making contact with the gate electrodes of the selection transistors in the second direction, wherein

the internal electrodes in the storage capacitors in two adjacent memory cells are connected to one another to produce a series circuit comprising the first selection transistor, the first storage capacitor, the second storage capacitor and the second selection transistor in the two adjacent memory cells, the active regions of the first and second selection transistors not being connected by means of the bit line which makes contact with the first and second selection transistors.

2. The test structure as claimed in claim 1 , wherein the storage capacitors are trench capacitors and the internal electrodes in the trench capacitors in two adjacent memory cells in the first direction are connected to one another via a tunnel structure.

3. A test structure for determining the electrical properties of memory cells, comprising:

a selection transistor and a storage capacitor, in a matrix-like cell array, where the selection transistors have an active region with a gate electrode, where the active region is conductively connected to a bit line and an internal electrode in the storage capacitor, and the gate electrode is conductively connected to a word line, where the active regions of the selection transistors are arranged in rows in a first direction, and the storage capacitors are arranged in rows in a second direction, which runs transversely with respect to the first direction, where the conductive connection between the active region of the selection transistor and the internal electrode in the storage capacitor in the memory cells on overlapping areas of the crossing rows of active regions and storage capacitors is respectively produced in a single edge region of the overlapping area, where the bit lines run in the first direction, making contact with the active regions of the selection transistors in the first direction, and the word lines run in the second direction, making contact with the gate electrodes of the selection transistors in the second direction, wherein

the internal electrode in a storage capacitor in a memory cell has a further conductive connection at the edge region of the overlapping area in the first direction, at which edge region the conductive connection is produced between the active region of the selection transistor and the internal electrode in the storage capacitor, to a bit line which is adjacent to the bit line which makes contact with the active region of the selection transistor.

4. The test structure as claimed in claim 3 , wherein the internal electrodes in the storage capacitors in a multiplicity of memory cells have a further conductive connection at the edge region of the overlapping area in the first direction, at which edge region the conductive connection is produced between the active region of the selection transistor and the internal electrode in the storage capacitor, to a bit line which is adjacent to the bit line which makes contact with the active region of the selection transistor, the length of the associated active regions of the selection transistors and/or the width of the associated gate electrode with the word line varying.

5. The test structure as claimed in claim 3 , wherein the storage capacitors are trench capacitors which have a substantially rectangular cross section in plan view, the conductive connection between the active region of the selection transistor and the internal electrode in the trench capacitor and the conductive connection between the internal electrode in the trench capacitor and the bit line which is adjacent to the bit line which makes contact with the active region of the selection transistor being produced on one longitudinal side of the rectangular cross section of the trench capacitor.