Process compatibility improvement by fill factor modulation

US10579768B2 · kind B2 · utility

Assignee

• KLA-TENCOR CORPORATION · US

Inventors

• Vladimir Levinski · Milpitas, US
• Eitan Hajaj · Ashkelon, IL
• Tal Itzkovich · Bet Shemesh, IL
• Sharon Aharon · Hanaton, IL
• Michael Adel · Zichron Ya'akov, IL
• Yuri Paskover · Or Akiva, IL
• Daria Negri · Nesher, IL
• Yuval Lubashevsky · Haifa, IL
• Amnon Manassen · Haifa, IL
• Myungjun Lee · Yongin-si, KR
• Mark D. Smith · Austin, US

Key dates

• Filing date: Nov 4, 2016
• Grant date: Mar 3, 2020
• Expiry date: Nov 4, 2036

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/027
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Metrology targets and target design methods are provided, in which target elements are defined by replacing elements from a periodic pattern having a pitch p, by assist elements having at least one geometric difference from the replaced elements, to form a composite periodic structure that maintains the pitch p as a single pitch. Constructing targets within the bounds of compatibility with advanced multiple patterning techniques improves the fidelity of the targets and fill factor modulation enables adjustment of the targets to produce sufficient metrology sensitivity for extracting the overlay while achieving process compatibility of the targets.