Multiple patterning with mandrel cuts defined by block masks
US11417525B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 2018 |
| Grant date | Aug 16, 2022 |
| Priority date | — |
| Expiry date | Jul 16, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76816
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Methods of self-aligned multiple patterning. A hardmask is deposited over an interlayer dielectric layer. A mandrel is formed over the hardmask. A block mask is formed that covers a first lengthwise section of the mandrel and that exposes second and third lengthwise sections of the mandrel. After forming the block mask, the second and third lengthwise sections of the mandrel are removed to define a pattern including respective first and second mandrel lines that are separated from each other by the first lengthwise section of the mandrel. The first mandrel line and the second mandrel line expose respective portions of the hardmask, and the first lengthwise section of the mandrel line covers another portion of the hardmask. The pattern is transferred to the hardmask with an etching process, and subsequently transferred to the interlayer dielectric layer with another etching process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.