Structure for critical dimension and overlay measurement

US8823936B2 · kind B2 · utility

Assignee

• Shanghai Huali Microelectronics Corporation · CN

Inventors

• Yunqing Dai · Shanghai, CN
• Jian Wang · Beijing, CN
• Zhibiao Mao · Shanghai, CN

Key dates

• Filing date: Nov 2, 2012
• Grant date: Sep 2, 2014
• Expiry date: Nov 2, 2032

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/70633
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

The invention provides a structure for critical dimension and overlay measurement including a measuring unit, a first measurement pattern for measuring overlay and a second measurement pattern for measuring linewidth, line density and/or line semi-density. The first target pattern includes an outer bar structure disposed on a first layer and an inner bar structure disposed on a second layer; the outer bar structure and/or the inner bar structure has a same shared pattern structure with the second target pattern. The pattern structure includes four bars with the same shape positioned orthogonally and closely to each other, and at least two orthogonally positioned bars include N equally spaced rectangular lines of the same width, wherein, N is an odd number; the N rectangular lines include one central rectangular line and N−1 auxiliary rectangular lines.