Simax’s new “Yield Plus” upgrade features a set of engineering tools that empower a lithographer to quickly, accurately, and efficiently quantify and characterize specific stepper/scanner system parameters leading to the full optimization of a given process’ yield.

At the heart of the “Yield Plus” system is a customized test reticle, and a revolutionary low-contact Wafer Chuck. The Yield Plus reticle provides precise and accurate lens image plane data  as well as wafer-level  topography data. Coupled with these data is the improved vacuum clamping design of the Yield Plus Chuck. This new design significantly improves wafer flatness at the wafer’s edge and at the same time improves the feed forward focus and leveling performance of any stepper/scanner utilizing this upgrade.

“Yield Plus” Upgrade Advantages

Independent tests have shown that the “Yield Plus” upgrade significantly improves tool utilization, process yield, and the reduction of rework. Moreover, the ability to quantitatively identify the root causes of many failure mechanisms has been of great utility to lithography engineers in reducing tool downtime, and hence increasing the tools ROI.

 

Reported Benefits

• Increased yield - up to 3%
• Early warning of yield reduction
• Improved CD uniformity
• Improved overlay performance
• Improved edge field leveling
• SPC lens focal plane monitoring of critical imaging parameters
• Chuck contamination monitoring
• Chuck damage monitoring
• In-depth analysis of systematic yield loss 

The “Yield Plus” Application Package

• A combination of specialized software and hardware
• Engineering tools to determine root cause of yield loss
• Software for chuck flatness analysis
• Software for lens image plane analysis and SPC
• Software to optimize image plane tilt and focus
• Ultra flat wafer chuck with improved clamping design
• Customized test reticle provides high accuracy focal plane measurements.