Trench capacitor field shield with sidewall contact
AssigneeInternational Business Machines Corporation
InventorWendell P. Noble, Jr.
Life of this patent
Estimating the term…
Abstract
Structures and methods are presented for forming a field shield for a trench capacitor for a memory cell with a contact through insulator along a sidewall of the trench to a desired region of the semiconducting substrate. The desired region is typically held at a substantially fixed potential; in any case it does not include a node diffusion.
Claims19
A storage capacitor having two electrodes formed in a trench having sidewalls and a bottom wall, the trench located in a semiconductor substrate, the capacitor comprising:
- a layer of insulator on walls of the trench;
- a layer of electrically conductive material on said layer of insulator;
- a node diffusion, one of the electrodes contacting said node diffusion and
- an electrically conductive member connected to said layer of electrically conductive material, extending through a sidewall portion of said layer of insulator, and contacting a selected region of the substrate other than said node diffusion.
A storage capacitor formed in a trench having sidewalls and a bottom wall, the trench located in a semiconductor substrate, the semiconductor substrate having a plurality of layers of differing impurity type and concentration, at least one of which is held at a substantially fixed potential, the capacitor comprising:
- a layer of insulator deposited on walls of the trench;
- a layer of electrically conductive material deposited on said layer of insulator;
- and
- an electrically conductive member connected to said layer of electrically conductive material, extending though a sidewall portion of said layer of insulator, and contacting a selected region of the substrate that is held at a substantially fixed potential.
A memory cell with a transfer device and a storage capacitor, the storage capacitor formed in a trench having sidewalls and a bottom wall, the trench located in a semiconductor substrate, the semiconductor substrate having a plurality of layers of differing impurity type and concentration, at least one of which is held at a fixed potential, the memory cell comprising:
- a layer of insulator on walls of the trench;
- a layer of electrically conductive material on said layer of insulator;
- an electrically conductive member connected to said layer of electrically conductive material, extending though a sidewall portion of said layer of insulator, and contacting a selected region of the substrate that is held at a fixed potential;
- and
- a transfer device comprising a bit line contact and diffusion, a gate, and a node diffusion, said node diffusion electrically connected to a storage electrode of the capacitor.
A memory cell with a transfer device and a capacitor, the capacitor formed in a trench having sidewalls and a bottom wall, the trench located in a semiconductor substrate, the memory cell comprising:
- a layer of insulator on walls of the trench;
- a layer of electrically conductive material on said layer of insulator;
- a transfer device comprising a bit line contact and a diffusion, a gate, and a node diffusion, said node diffusion electrically connected to a storage node of the capacitor;
- and
- an electrically conductive member connected to said layer of electrically conductive material, said member extending through a sidewall portion of said layer of insulator, said member contacting a selected region of the substrate, said region not contacting said node diffusion.
A trench sidewall connector in a semiconductor substrate, comprising:
- a semiconductor substrate;
- a trench in the substrate, said trench having a sidewall;
- and
- a conductive layer within said trench at least in part spaced from said sidewall, said layer having an outer and an inner surface, said layer making electrical contain with a portion of said sidewall, said layer held at a substantially fixed potential when in operation.
Dependencies are inferred from the claim text.