Macro Wafer Defect Inspection, Metrology and Review Cluster Tool
CIRCL™ is a cluster tool with four modules, covering all macro wafer surfaces and providing parallel data collection at high throughput for efficient process control. The modules comprising CIRCL include: front side macro wafer defect inspection; wafer edge defect inspection, profile and metrology; back side wafer defect inspection and review; and, optical review and classification of front side and edge defects. Data collection is controlled by DirectedSampling™, an innovative approach that uses results from one measurement to trigger other types of measurements within the cluster. The CIRCL tool is utilized for multiple applications within the fab, including lithography process monitoring and 3D metrology for outgoing quality control. The modular configuration of CIRCL offers flexibility for varying process control needs, saves overall fab space, reduces wafer queue time, and provides a cost-effective upgrade path to protect a fab’s capital investment.
LDS3400: Front side macro wafer defect inspection module
CV310i: Wafer edge defect inspection, profile and metrology module
BDR300: Back side wafer defect inspection and review module
INS: Optical defect review and classification module
Process Monitor: With high throughput and a modular design, CIRCL provides comprehensive data for process monitoring. The use of DirectedSampling within the module results in actionable data that can accelerate root-cause determination. Furthermore, tool-to-tool matching for each module within CIRCL facilitates flexible WIP routing and the best baseline stability.
Lithography: CIRCL is ideally suited for use within the lithography cell. The front side defect inspection module captures a wide range of critical litho defects including particles, defocus defects spanning several die and full-wafer missing resist. The optical defect review and classification module provides several SpotCheck applications including Reticle ID check to verify that the correct reticle was used to print the wafer and macro overlay error monitoring to check layer-to-layer pattern registration. The back side defect inspection and review module detects contamination and scratches that can result in defocus issues when printing pattern on the wafer front side. The edge module’s inspection capability is used to detect edge defects and film delamination that could be transported to the pattern areas during immersion lithography causing yield loss. Finally, the edge module’s metrology capability is used to characterize the EBR concentricity of BARC, resist and topcoat process layers in the litho stack, helping engineers to identify overlapping film edges that can lead to film delamination and increased defectivity for immersion lithography. Through high-throughput, parallel collection of multi-surface wafer data, CIRCL enables lithography engineers to quickly identify critical issues and take fast corrective action to prevent yield loss.
Outgoing Quality Control (OQC): CIRCL provides 3D macro wafer shape metrology, enabling outgoing quality control for advanced packaging. In addition to front side wafer defect inspection, wafer edge inspection and edge metrology, CIRCL measures X, Y and height (Z) for complete characterization of PAD layers.
For other macro patterned wafer defect inspection tools, please see K-T Certified.