Paper
24 May 2004 Logic gate scanner focus control in high-volume manufacturing using scatterometry
Richard J Dare, Bryan Swain, Michael Laughery
Author Affiliations +
Abstract
Tool matching and optimal process control are critical requirements for success in semiconductor manufacturing. It is imperative that a tool’s operating conditions are understood and controlled in order to create a process that is repeatable and produces devices within specifications. Likewise, it is important where possible to match multiple systems using some methodology, so that regardless of which tool is used the process remains in control. Agere Systems is currently using Timbre Technologies’ Optical Digital Profilometry (ODP) scatterometry for controlling Nikon scanner focus at the most critical lithography layer; logic gate. By adjusting focus settings and verifying the resultant changes in resist profile shape using ODP, it becomes possible to actively control scanner focus to achieve a desired resist profile. Since many critical lithography processes are designed to produce slightly re-entrant resist profiles, this type of focus control is not possible via Critical Dimension Scanning Electron Microscopy (CDSEM) where reentrant profiles cannot be accurately determined. Additionally, the high throughput and non-destructive nature of this measurement technique saves both cycle time and wafer costs compared to cross-section SEM. By implementing an ODP daily process check and after any maintenance on a scanner, Agere successfully enabled focus drift control, i.e. making necessary focus or equipment changes in order to maintain a desired resist profile.
© (2004) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Richard J Dare, Bryan Swain, and Michael Laughery "Logic gate scanner focus control in high-volume manufacturing using scatterometry", Proc. SPIE 5375, Metrology, Inspection, and Process Control for Microlithography XVIII, (24 May 2004); https://doi.org/10.1117/12.533835
Lens.org Logo
CITATIONS
Cited by 1 scholarly publication.
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Scanners

Lithography

Process control

Semiconducting wafers

Control systems

Photoresist materials

Scatterometry

RELATED CONTENT


Back to Top