Patent ID: 11935889
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 16:
17. A method comprising:
etching a semiconductor substrate to form a crown-shaped semiconductor strip, wherein the etching comprises:
performing a first etching process on the semiconductor substrate to form a plurality of semiconductor strips, wherein an outmost semiconductor strip in the plurality of semiconductor strips comprises a first outer edge;
forming a blanket photo resist;
performing a patterning process on the blanket photo resist to form a patterned photo resist comprising a portion covering the plurality of semiconductor strips, wherein the first outer edge of the outmost semiconductor strip in the plurality of semiconductor strips is in contact with a sidewall of the portion of the patterned photo resist; and
performing a second etching process to form a semiconductor base directly underlying the plurality of semiconductor strips, wherein the semiconductor base comprises a second outer edge vertically aligned to the first outer edge, and wherein during the second etching process, the portion of the patterned photo resist is removed to reveal the first outer edge of the outmost semiconductor strip.