RRAM structure at STI with Si-based selector

摘要

An RRAM at an STI region is disclosed with a vertical BJT selector. Embodiments include defining an STI region in a substrate, implanting dopants in the substrate to form a well of a first polarity around and below an STI region bottom portion, a band of a second polarity over the well on opposite sides of the STI region, and an active area of the first polarity over each band of second polarity at the surface of the substrate, forming a hardmask on the active areas, removing an STI region top portion to form a cavity, forming an RRAM liner on cavity side and bottom surfaces, forming a top electrode in the cavity, removing a portion of the hardmask to form spacers on opposite sides of the cavity, and implanting a dopant of the second polarity in a portion of each active area remote from the cavity.

主权项

1. A device comprising:
a substrate; a well of a first polarity in the substrate; a shallow trench isolation (STI) region formed in the substrate extending partially into the well; bands of a second polarity in the substrate, over the well, at opposite sides of the STI region; an area of the first polarity at a top surface of the substrate over each band; an area of the second polarity in the substrate over each band, adjacent each area of the first polarity and remote from the STI region; a recess in a top portion of the STI region, wherein a bottom surface of the recess is above a top surface of the band; a resistive random access memory (RRAM) liner on side and bottom surfaces of the recess; and a top electrode in the recess.