Semiconductor memory having an arrangement of memory cells
A semiconductor memory can have first lines to which memory cells are connected and that run divergently with respect to one another, and second lines to which the memory cells are connected that are curved. Combining the geometry of the memory cell array with storage capacitors laterally offset allows signal delays along word lines and bit lines to be aligned regardless of the position of a memory cell in the memory cell array. The geometry of the memory cell array allows short signal propagation times to be attained particularly along the first lines, which are divergent with respect to one another, this simplifying error-free operation of a semiconductor memory particularly at high clock frequencies.
1. A semiconductor memory, comprising:
a plurality of memory cells forming at least one memory cell array, the memory cells being connected to first lines and to second lines, the second lines crossing the first lines, each memory cell having a storage capacitor and a selection transistor, wherein the first lines run divergently with respect to one another, the second lines are curved, a memory cell is connected at each crossing point between a first line and a second line, each of the first lines has memory cells connected thereon, and respective storage capacitors are laterally offset alternately on each side of the respective first lines.
2. The semiconductor memory as claimed in claim 1 , wherein the first lines extend divergently from a logic area to the memory cells in at least one memory cell array.
3. The semiconductor memory as claimed in claim 1 , wherein the at least one memory cell array forms an annular portion, the first lines diverging radially, and the second lines curving arcuately.
4. The semiconductor memory as claimed in claim 1 , wherein one or more memory cell arrays surround a logic area annularly.
5. The semiconductor memory as claimed in claim 1 , wherein the first lines are bit lines and the second lines are word lines.
6. The semiconductor memory as claimed in claim 1 , wherein the first lines are word lines and the second lines are bit lines.
7. The semiconductor memory as claimed in claim 1 , wherein one of the first and second lines are bit lines and the other of the first and second lines are word lines and two memory cells are connected to two mutually adjacent bit lines and to the same word line, the two memory cells having respective storage capacitors adjacent to one another along the same word line.
8. The semiconductor memory as claimed in claim 1 , wherein the storage capacitors are trench capacitors buried in a semiconductor substrate.
9. The semiconductor memory as claimed in claim 4 , wherein at least one further logic area is provided on a semiconductor substrate and is arranged between a memory area and an edge of the semiconductor substrate, the further logic area not being surrounded by memory areas.
10. The semiconductor memory as claimed in claim 1 , wherein the first lines or the second lines are word lines and the selection transistors are vertical field effect transistors whose gate electrodes are connected to the word lines.
11. The semiconductor memory as claimed in claim 1 , wherein the semiconductor memory is a dynamic read/write memory.
12. The semiconductor memory as claimed in claim 1 , wherein the first lines run divergently in non-parallel directions along their extent.
13. The semiconductor memory as claimed in claim 1 , wherein the first lines are continuously divergent along their extent.
14. The semiconductor memory as claimed in claim 1 , wherein the second lines extend along concentric arcs.
15. A semiconductor memory, comprising:
a plurality of memory cells forming at least one memory cell array, the memory cells being connected to first lines and to second lines, the second lines crossing the first lines, each memory cell having a storage capacitor and a selection transistor, wherein the first lines run divergently with respect to one another, the second lines are curved, a memory cell is connected at each crossing point between a first line and a second line, each of the second lines has memory cells connected thereon, and respective storage capacitors are laterally offset alternately on each side of the respective second lines.
16. The semiconductor memory as claimed in claim 15 , wherein the first lines extend divergently from a logic area to the memory cells in at least one memory cell array.
17. The semiconductor memory as claimed in claim 15 , wherein the at least one memory cell array forms an annular portion, the first lines diverging radially, and the second lines curving arcuately.
18. The semiconductor memory as claimed in claim 15 , wherein one or more memory cell arrays surround a logic area annularly.
19. The semiconductor memory as claimed in claim 15 , wherein the first lines are bit lines and the second lines are word lines.
20. The semiconductor memory as claimed in claim 15 , wherein the first lines are word lines and the second lines are bit lines.
21. The semiconductor memory as claimed in claim 15 , wherein one of the first and second lines are bit lines and the other of the first and second lines are word lines and two memory cells are connected to two mutually adjacent bit lines and to the same word line, the two memory cells having respective storage capacitors adjacent to one another along the same word line.
22. The semiconductor memory as claimed in claim 15 , wherein the storage capacitors are trench capacitors buried in a semiconductor substrate.
23. The semiconductor memory as claimed in claim 18 , wherein at least one further logic area is provided on a semiconductor substrate and is arranged between a memory area and an edge of the semiconductor substrates the further logic area not being surrounded by memory areas.
24. The semiconductor memory as claimed in claim 15 , wherein the first lines or the second lines are word lines and the selection transistors are vertical field effect transistors whose gate electrodes are connected to the word lines.
25. The semiconductor memory as claimed in claim 15 , wherein the semiconductor memory is a dynamic read/write memory.
26. The semiconductor memory as claimed in claim 15 , wherein the first lines run divergently in non-parallel directions along their extent.
27. The semiconductor memory as claimed in claim 15 , wherein the first lines are continuously divergent along their extent.
28. The semiconductor memory as claimed in claim 15 , wherein the second lines extend along concentric arcs.
29. A semiconductor memory, comprising:
a centrally-located logic area for operating the semiconductor memory;
at least one memory array surrounding the logic area;
first lines extending outward from the logic area into the at least one memory array;
second lines extending through the at least one memory array along a periphery of the logic area and arranged concentrically with respect to the logic area such that the first and second lines form a non-rectangular array of crossing points; and
a plurality of memory cells coupled to the first and second lines at the crossing points, the memory cells including storage capacitors laterally offset alternately on each side of respective first lines or respective second lines.