Semiconductor memory
View Patent ↗The object of providing a non-volatile semiconductor memory that stands out by good scalability and a high retention time as well as ensures low switching voltages at low switching times and achieves a great number of switching cycles at good temperature stability is solved by the present invention with a semiconductor memory whose memory cells comprise at least one silicon matrix material layer with open or disturbed nanocrystalline or amorphous network structures and structural voids which has a resistively switching property between two stable states, utilizing the ion drift in the silicon matrix material layer. The memory concept suggested in the present invention thus offers an alternative to the flash and DRAM memory concepts since it is not based on the storing of charges, but on the difference of the electric resistance between two stable states that are caused by the mobility of ions in the amorphous silicon matrix material with an externally applied electric field.
1. A semiconductor memory, comprising:
a number of memory cells each arranged at the crosspoints of a memory cell matrix constructed of electric supply lines that are connected with the memory cell via electrodes, the memory cell comprising:
a plurality of material layers, and
at least one silicon matrix material layer with open or disturbed nanocrystalline or amorphous network structures and structural voids, having a resistively switching property between two stable states, utilizing an ion drift in the silicon matrix material layer.
2. The semiconductor memory according to claim 1 , wherein the silicon matrix material layer include a chemically inert and porous, amorphous, micromorphous or microcrystalline silicon matrix material with structure voids and has a bistable behavior due to its ion conductivity, such that the memory cell is adapted to assume two stable states with different mobility of ions available in the silicon matrix material layer and with different electric resistances under an influence of an electric field.
3. The semiconductor memory according to claim 1 , wherein the structure of the silicon matrix material layer is formed by conglomerated nanoparticles and mobility of the ions in the silicon matrix material layer is effected by channel-like, open regions in the structure of the silicon matrix material layer.
4. The semiconductor memory according to claim 1 , wherein structural gaps of the structural voids serve as channels for conducting the ions available in the silicon matrix material.
5. The semiconductor memory according to claim 1 , wherein the silicon matrix material layer is doped with alkali, earth alkali and/or metal ions.
6. The semiconductor memory according to claim 1 , wherein the material layers of the memory cell are arranged in one of a following positions: on top of each other, side by side, or in a sandwiched layer stack, on a semiconductor substrate.
7. The semiconductor memory according to claim 1 , wherein the resistively switching, non-volatile memory cell comprises at least of the following material layers:
a first electrode;
an amorphous, micromorphous or microcrystalline silicon matrix material layer doped with alkali, earth alkali or metal ions;
a layer serving as an ion reservoir; and
a second electrode.
8. The semiconductor memory according to claim 1 , wherein the resistively switching, non-volatile memory cell comprises at least of the following material layers:
a first electrode;
a strongly ion-doped silicon layer;
a non-doped silicon layer;
a layer serving as an ion reservoir; and
a second electrode.
9. The semiconductor memory according to claim 1 , wherein the resistively switching, non-volatile memory cell comprises at least of the following material layers:
a first electrode;
a weakly doped silicon layer;
a strongly doped silicon layer;
a layer serving as an ion reservoir; and
a second electrode.
10. The semiconductor memory according to claim 9 , wherein the double layer is alternatively designed as a single silicon layer comprising a doping profile that proceeds from strong doping to weak doping.
11. The semiconductor memory according to claim 1 , wherein the amorphous, micromorphous or microcrystalline silicon material comprises amorphous Si:H, amorphous Si:C, H, amorphous Si:H, O, μc-Si, or SiOx (with x=1 . . . 2).
12. The semiconductor memory according to claim 1 , wherein the electrodes are manufactured of inert and refractory elements.
13. The semiconductor memory according to claim 1 , wherein the memory cell is manufactured by a CMOS process-compatible method.
14. A system with a memory device, comprising:
at least one semiconductor memory with memory cells comprising:
a plurality of material layers, and
at least one silicon matrix material layer with open or disturbed nanocrystalline or amorphous network structures and structural voids, having a resistively switching property between two stable states, utilizing an ion drift in the silicon matrix material layer.