Compact localized RRAM cell structure realized by spacer technology

摘要

An RRAM is disclosed with a vertical BJT selector. Embodiments include defining a STI region in a substrate, implanting dopants in the substrate to form a first polarity well around and below a bottom portion of the STI region, a second polarity channel over the well on opposite sides of the STI region, and a first polarity active area over each channel at the surface of the substrate, forming an RRAM liner on the active area and STI region, forming a sacrificial top electrode on the RRAM liner, forming spacers on opposite sides of the sacrificial top electrode, implanting a second polarity dopant in the active area on opposite sides of the sacrificial top electrode, forming a silicon oxide adjacent the spacers, removing at least a portion of the sacrificial top electrode forming a cavity, forming in the cavity inner spacers adjacent the spacers and a top electrode.

主权项

1. A method comprising:
defining a shallow trench isolation (STI) region in a substrate; implanting dopants in the substrate to form a well of a first polarity around and below a bottom portion of the STI region, a channel of a second polarity over the well on opposite sides of the STI region, and an active area of the first polarity over each channel of second polarity at the surface of the substrate; forming an RRAM liner on the active area and STI region; forming a sacrificial top electrode on the RRAM liner; forming spacers on opposite sides of the sacrificial top electrode and RRAM liner; implanting a dopant of the second polarity in the active area on opposite sides of the sacrificial top electrode; forming a silicon oxide adjacent the spacers; removing at least a portion of the sacrificial top electrode, forming a cavity; forming inner spacers, adjacent the spacers, in the cavity; and forming a top electrode in the cavity.