By Will Soutter
KLA-Tencor has introduced an overlay metrology system called the Archer 500 for key chipmakers to take overlay error measurements for developing and mass-producing multi-patterning process layers at sub-28 nm design nodes.
Archer 500 Tool
The Archer 500 makes measurements and characterizations of overlay errors with better precision and measurement speed than its forerunner, the proven Archer 300. With substantial contrast improvements, the metrology system extends overlay measurement capability to new lithography layers such as complex thin resist stacks and new materials like opaque hard masks. It acts as an independent source providing overlay metrology data inside a lithography cell.
The Archer 500’s high accuracy and fast measurement speed allow for detailed overlay characterization on wafers subsequent to patterning in order to check the alignment of that pattern features with previously-patterned features, positioned either on a previous process layer or on the same layer. For mass production, the Archer 500 is engineered to detect wafers with overlay error beyond the required specifications, facilitating lithographers precisely disposition wafers and make a decision on when to handle changes in process tool performance. Its total measurement uncertainty and tighter precision enables rigorous specifications needed for overlay control on advanced devices.
The Archer 500 system demonstrates high-throughput and fast move-acquire-measurement, enabling lithographers to capture more measurements on wafers for enhanced process control and characterization. Several key logic and memory chipmakers have placed multiple orders, which include numerous repeat orders, for KLA-Tencor’s Archer 500 tools. The company has already shipped several systems for sophisticated development and production lines. Archer 500 models are compatible to last-generation Archer 200 and Archer 300 systems, thus protecting the facility’s baseline and allowing smooth production integration rapidly.