Patent ID: 11908732
Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
Field: Semiconductors (Electrical engineering)
Classification: CPC H  G | IPC G  H

Claim 9:
10. A method of forming a pitch pattern, comprising:
forming two adjacent mandrels separated by a first distance, D1, on a substrate;
forming a first sidewall spacer on opposite sides of each of the two adjacent mandrels, wherein the first sidewall spacers are made of a first material;
removing the two adjacent mandrels;
forming a second sidewall spacer adjoining each of the first sidewall spacers after the removing the two adjacent mandrels, where the second sidewall spacers are made of a second material different from the first material;
forming a third sidewall spacer adjoining each of the second sidewall spacers, where the third sidewall spacers are made of the first material; and
forming a fourth sidewall spacer adjoining each of the third sidewall spacers, where the fourth sidewall spacers are made of the second material.