Integrated circuit having a resistive memory
View Patent ↗An integrated semiconductor memory includes a storage medium ( 6 ) arranged between two electrodes ( 10, 20 ), which storage medium may be a phase change medium, for example. The storage medium ( 6 ) can be put into a first state or a second state by means of an electric current, as a result of which an item of information can be stored. According to embodiments of the invention, a layer plane (L) is provided in which impurity particles made from a material ( 4 ) are embedded, as a result of which the current density in the storage medium is locally increased and the programming current required for reprogramming is reduced. As a result, the current consumption of memory elements containing a phase change medium is reduced, so that for the first time they can be embodied with minimal feature size, together with other components such as transistors, and integrated into a single semiconductor circuit and no longer have to be arranged in separate subcircuits.
1. An integrated circuit having a resistive memory comprising:
a first electrode;
a second electrode; and
a storage portion between the first electrode and the second electrode, the storage portion comprising a storage medium and regions made of a material different than the storage medium, the regions having dimensions smaller than a feature size that can be dimensioned with lithography used to pattern the storage medium, and the regions made from the different material comprising patterned regions of a patterned electrically insulating layer.
2. The integrated circuit as claimed in claim 1 , wherein the material is surrounded by the storage medium.
3. The integrated circuit as claimed in claim 1 , wherein the material is arranged directly on an interface with a carrier layer.
4. The integrated circuit as claimed in claim 3 , wherein the carrier layer comprises an electrode layer.
5. The integrated circuit as claimed in claim 4 , wherein an area proportion of the interface with the carrier layer of between 0.01% and 90% is covered by the storage medium.
6. The integrated circuit as claimed in claim 5 , wherein an area proportion of the interface with the carrier layer of between 0.01% and 5% is covered by the storage medium.
7. The integrated circuit as claimed in claim 5 , wherein an electric current flowing through the storage medium can be fed with the aid of the first and second electrodes.
8. The integrated circuit as claimed in claim 1 , wherein the storage medium is electrically conductively connected to the first electrode and to the second electrode.
9. The integrated circuit as claimed in claim 1 , wherein the regions made from the material comprise isolated islands having an average diameter of between 0.5 nm and 100 nm.
10. The integrated circuit as claimed in claim 1 , wherein the material comprises nanocrystalline particles or an amorphous insulator.
11. The integrated circuit as claimed in claim 1 , wherein the storage medium has a lower degree of crystallization in a first state and a higher degree of crystallization in a second state.
12. The integrated circuit as claimed in claim 1 , wherein the storage medium contains a chalcogenide or a pnicogenide.
13. The integrated circuit as claimed in claim 1 , wherein the resistive memory comprises a nonvolatile phase change memory.