Phase change memory elements having a confined portion of phase change material on a recessed contact
AssigneeSamsung Electronics Co., Ltd.
InventorsJoon-sang Park, Chang-ki Hong, Sang-yong Kim
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Abstract
Methods of fabricating phase change memory elements include forming an insulating layer on a semiconductor substrate, forming a through hole penetrating the insulating layer, forming a lower electrode in the through hole and forming a recess having a sidewall comprising a portion of the insulating layer by selectively etching a surface of the lower electrode relative to the insulating layer. A phase change memory layer is formed on the lower electrode. The phase change memory layer has a portion confined by the recess and surrounded by the insulating layer. An upper electrode is formed on the phase change memory layer. Phase change memory elements are also provided.
Claims8
A phase change memory element, comprising:
- an insulating layer on a semiconductor substrate, the insulating layer having a through hole penetrating the insulating layer;
- a lower electrode in a recess in the through hole, wherein the recess has a sidewall comprising a portion of the insulating layer;
- a phase change memory layer on the lower electrode, the phase change memory layer having a portion confined by the recess and surrounded by the insulating layer;
- an upper electrode on the phase change memory layer;
- and
- an oxide layer disposed between the lower electrode and the portion of the phase change material layer confined in the recess.
A phase change memory element, comprising:
- an insulating layer on a semiconductor substrate, the insulating layer having a through hole penetrating the insulating layer;
- a lower electrode in a recess in the through hole, wherein the recess has a sidewall comprising a portion of the insulating layer;
- a phase change memory layer on the lower electrode, the phase change memory layer having a portion confined by the recess and surrounded by the insulating layer;
- an upper electrode on the phase change memory layer;
- and
- a spacer on a sidewall of the through hole such that a transverse cross-sectional area of the lower electrode in the through hole is smaller than a transverse-cross-sectional area of the through hole,
- wherein the spacer comprises:
- a first spacer layer on the sidewall of the through hole;
- and
- a second spacer layer on the first spacer layer;
- and
- wherein the first spacer layer comprises a first insulating material having a first step coverage characteristic and the second spacer layer comprises a second insulating material having a second step coverage characteristic indicating less step coverage than the first insulating material.
Dependencies are inferred from the claim text.