Lower electrode isolation in a double-wide trench
AssigneeOvonyx, Inc.
InventorCharles Dennison
Life of this patent
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Abstract
The invention relates to a phase-change memory device. The device includes a double-wide trench into which a single film is deposited but two isolated lower electrodes are formed therefrom. Additionally a diode stack is formed that communicates to the lower electrode. Additionally, other isolated lower electrodes may be formed along a symmetry line that is orthogonal to the first two isolated lower electrodes. The present invention also relates to a method of making a phase-change memory device. The method includes forming two orthogonal and intersecting isolation structure s around a memory cell structure diode stack.
Claims19
A phase-change memory device comprising:
- spaced-apart first and second active areas that are disposed in a substrate;
- a recess comprising a bottom and walls, wherein the recess communicates to the first active area and the second active area;
- and
- a polysilicon film disposed in the recess, wherein the polysilicon film has a first conductivity at the bottom and a second conductivity at the walls.
A memory device comprising:
- in a substrate, a trench that exposes first, and second active areas along a first symmetry line and that exposes the first and a third active area along a second symmetry line that is orthogonal to the first symmetry line;
- a polysilicon film disposed in the trench, wherein the polysilicon film contacts the first and third active areas;
- and
- a phase-change memory element disposed above the first active area.
An apparatus comprising:
- a dedicated memory ship having a first plurality of address lines and a second plurality of address lines, addressing circuitry coupled to the first plurality of address lines and second plurality of address lines, a plurality of memory cells formed between respective ones of the plurality of first address lines and the plurality of second address lines, each memory cell including spaced-apart first and second active areas that are disposed in a substrate, a recess including a bottom and walls, wherein the recess communicates to the first active area and the second active area, a polysilicon film disposed in the recess, wherein the polysilicon film has a first conductivity at the bottom and a second conductivity at the walls.
Dependencies are inferred from the claim text.