Method of making a dynamic ram cell having shared trench storage

Details Method of making a dynamic ram cell having shared trench storage Method of making a dynamic ram cell having shared trench storage

1988-08-29

1989-05-23

Chaudhuri, Olik

Fishing, trapping, and vermin destroying

437 52, 437 60, 437186, 437193, 437203, 437228, 437919, H01L 2710

Patent

active

048330949

ABSTRACT:
A one-device shared trench memory cell, in which the polysilicon and dielectric layers within the trench extend above the surface of the trench to form a mandrel structure. A layer of polysilicon is conformably deposited on the mandrel structure. Dopant ions are diffused from the doped polysilicon within the trench to the conformal polysilicon layer, and from the conformal polysilicon layer, and from the conformal polysilicon layer to a portion of the substrate disposed thereunder. The conformal polysilicon is etched in a solvent that preferentially attacks undoped polysilicon, to provide and is a bridge contact that is self-aligned to the polysilicon within the trench and to the diffusion region. A plurality of FETs formed on either side of the trench, by use of a sidewall-defined gate electrode to maximize density. The cell produces a "poly-to-poly" and "poly-to-substrate" storage capacitor combination that maximizes charge storage capability.

REFERENCES:
patent: 4262296 (1981-04-01), Shealy et al.
patent: 4446613 (1984-05-01), Beinglass et al.
patent: 4649625 (1987-03-01), Lu
patent: 4651184 (1987-03-01), Malhi
patent: 4670768 (1987-06-01), Sunami et al.
patent: 4672410 (1987-06-01), Miura et al.
patent: 4700457 (1987-10-01), Matsulcawa
patent: 4722908 (1988-02-01), Burton
patent: 4757029 (1988-07-01), Koury, Jr.
patent: 4771013 (1988-09-01), Curran
S. Naicajima et al., "An Isolation-Merged Vertical Capacitor-Cell for Large Capacity DRAM", pp. 240-243, IEDM 1984.

Affiliated with

Also associated with

Rating

Method of making a dynamic ram cell having shared trench storage does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of making a dynamic ram cell having shared trench storage, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of making a dynamic ram cell having shared trench storage will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1730713