Process control and yield management solutions provider KLA-Tencor Corp of Milpitas, CA, USA has introduced the WaferSight PWG patterned wafer geometry measurement system, the LMS IPRO6 reticle pattern placement metrology system, and the K-T Analyzer 9.0 advanced data analysis system. The three new products support KLA-Tencor’s 5D patterning control solution, which addresses five elements of patterning process control — the three geometrical dimensions of device structures, time-to-results, and overall equipment efficiency. The 5D patterning control solution is being developed to drive optimal patterning results through the characterization, optimization and monitoring of processes inside and outside the lithography module. By combining these measurements with intelligent feedback and feed-forward process control loops, the solution can help chipmakers to obtain faster, more cost-effective ramps of multi-patterning, spacer pitch splitting and other advanced patterning technologies using existing process equipment, says the firm.
“Process control serves a fundamental role in helping our customers navigate the near-zero process windows, shrinking overlay error budgets and other complexities associated with innovative patterning techniques,” says Ahmad Khan, group VP of KLA-Tencor’s Parametric Solutions Group. “Within the lithography module, our Archer 500 overlay and SpectraShape 9000 critical dimension advanced metrology systems identify and monitor patterning errors,” he adds. “Extending beyond the lithography cell, our new WaferSight PWG and LMS IPRO6 systems isolate additional process- or reticle-related sources of patterning errors. These fab-wide, comprehensive measurements, supported by K-T Analyzer 9.0’s flexible data analysis, expand the process window and enable improved production patterning control for our customers’ leading-edge devices.”
Installed at multiple IC manufacturers for development and production of advanced devices, the WaferSight PWG measures patterned wafer geometry after a wide range of processes, helping chipmakers identify and monitor variations that affect patterning. By incorporating what is claimed to be industry-unique vertical wafer hold to minimize gravitational distortion and a sampling density of 3.5 million data points per wafer, the WaferSight PWG produces highly accurate wafer shape data that can be fed forward to the lithography module for wafer shape-optimized scanner corrections that improve pattern overlay. The WaferSight PWG also uniquely measures the wafer’s front and back surfaces concurrently, generating wafer thickness metrics that are used to help reduce wafer-induced scanner focus errors. The WaferSight PWG is based on the WaferSight platform, which has strong adoption by worldwide wafer manufacturers for bare wafer geometry quality assurance, says KLA-Tencor.
The LMS IPRO6 is being used by leading-edge mask shops for comprehensive characterization of reticle pattern placement error (a direct contributor to wafer-level pattern overlay error). Proprietary model-based metrology allows the LMS IPRO6 to accurately measure reticle registration for on-device pattern features, as well as standard registration marks, offering significantly higher sampling for improved decisions on mask quality. With faster measurement time than its predecessor, the LMS IPRO6 supports the productivity required to qualify the increased number of reticles associated with innovative multi-patterning techniques. The LMS IPRO6 enables the generation of pattern-dependent registration error data that improves feedback to the electron-beam mask writer and can be fed forward to the fab’s lithography module for feature-optimized scanner corrections that improve wafer-level patterning.
Installed at foundry and memory manufacturers, K-T Analyzer 9.0 is the latest version of the industry standard platform that enables advanced run-time data analysis for a wide range of metrology system types, including overlay, reticle registration, wafer geometry, films, critical dimension and device profile metrology systems. K-T Analyzer 9.0 includes in-line methods for calculating scanner corrections per exposure on an on-product, lot-by-lot basis that maintains high accuracy without requiring full wafer measurement data — a production-capable control technique that can reduce pattern overlay error. In addition, K-T Analyzer 9.0 includes new scanner fleet management, scanner data analysis and scanner alignment optimization capabilities, offering chipmakers a flexible solution for improving scanner utilization and for monitoring and optimizing lithography processes.
WaferSight PWG, LMS IPRO6 and K-T Analyzer 9.0 are part of KLA-Tencor’s comprehensive 5D patterning control solution, which also includes overlay, films, critical dimension and device profile metrology systems and the PROLITH lithography and patterning simulator. The WaferSight PWG, LMS IPRO6 and K-T Analyzer 9.0 systems are backed by KLA-Tencor’s global, comprehensive service network.