Patent ID: 11877454
Assignee: SK HYNIX INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. The method of claim 1, wherein forming a plurality of multi-layer sacrificial structures including a sacrificial material over the exposed sacrificial layers of the stepwise structure comprises:
forming a sacrificial pad layer over a sacrificial layer;
etching the sacrificial pad layer to form a sacrificial pad;
sequentially depositing a buffer layer and an additional sacrificial pad layer over the sacrificial pad;
forming a sacrificial buffer pad over the additional sacrificial pad layer;
etching the additional sacrificial pad layer with the sacrificial buffer pad used as an etch mask to form the additional sacrificial pad; and
etching the buffer layer to form the buffer pad,
wherein the additional sacrificial pad and the sacrificial pad form a multi-layer sacrificial structure of the plurality of the multi-layer sacrificial structures.