Organic memory cell formation on Ag substrate
View Patent ↗Systems and methods are disclosed for creating memory cells on a silver interconnect substrate. The silver substrate is initially subject to a CMP process followed by cycles of exposure to inorganic and organic acids, as well as growing Ag/Ag 2 S layers. The resulting smooth Ag interconnect surface is then employed for basing the memory cell layers thereupon.
1. A method for fabricating an organic memory cell comprising:
forming a substrate silver layer having a surface that acts as a base for an organic memory cell to be created thereupon;
performing a CMP process on the surface;
exposing the post CMP surface to an inorganic acid for shaping a surface depression thereupon;
growing a passive layer within the depression; and
applying an organic acid to a surface of the grown passive layer, such that a substantially smooth surface texture is obtained.
2. The method of claim 1 , further comprising;
forming a dielectric layer over the passive layer; and
forming a layer of organic material over the passive layer.
3. The method of claim 1 , further comprising:
plating the passive layer by an electroless process.
4. The method of claim 3 , further comprising:
controlling the plating process by a controller.
5. The method of claim 1 , further comprising:
etching a surface protrusion of the passive layer to a post CMP surface level.
6. The method of claim 1 , further comprising:
exposing the post CMP surface to the inorganic acid in several cycles, and
applying the organic acid in several cycles.
7. A method for planarizing a CMP processed silver interconnect surface comprising:
providing a CMP processed silver interconnect having an initial surface with micro scratches;
exposing the initial surface to an inorganic acid for shaping a void thereupon;
growing a passive layer comprising Ag 2 S within the void, such that a surface of the passive layer forms a protrusion out of the void, extending beyond the initial surface; and
exposing the passive layer to an organic acid.
8. The method of claim 7 , further comprising:
selectively depositing an activation compound over the void;
applying a chemical solution to the activation compound as to initiate an electroless reaction, the chemical solution comprising silver metal ions as well as a reducing agent; and
reducing the metal ions of the chemical as to plate the passive layer within the void.
9. The method of claim 7 , further comprising:
growing an Ag 2 S or an Ag layer.
10. The method of claim 8 , further comprising:
employing at least one of an ammonium hydroxide, an ammonium carbonate, and an ammonium bicarbonate, in the chemical solution.
11. The method according of claim 8 , further comprising:
controlling the growing of the passive layer within the void.
12. The method according to claim 8 , further comprising:
employing a hydrazine reducer.