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Product Briefing Outline: KLA-Tencor has launched a new family of reticle inspection systems that takes into consideration the different needs of logic and memory fabs, as well as different mask generations. These include the ‘TeraFab SLQ-2X,’ which is designed for leading-edge logic fabs. The ‘TeraFab Q-3X’ is designed for multiple-die re-qualification and incoming quality control (IQC) applications common to memory fabs, and the ‘TeraFab SLQ-1X,’ which offers a lowest cost of ownership (CoO) alternative, is suited to go/no-go functions for single-die inspection typical of logic fab requalification applications. TeraFab systems are currently undergoing beta testing and evaluation at leading 45nm-generation logic and memory fabs, in Japan, Taiwan and Europe.

Problem: Traditional mask inspection within a fab has been for incoming quality inspection from the mask shop. However, reticles used for DUV applications are more susceptible to induced haze and crystal growth over time in production. There is now a need to detect and analyze all sources of contamination on the reticle before wafer exposure to eliminate yield.  According to a recent SEMATECH annual study, the rate of exposure-induced reticle contamination has increased fivefold with an 193nm ArF light source use when compared to 248nm KrF imaging.

Solution: The TeraFab mask inspection systems feature key advances in detection algorithm technology that can significantly reduce yield loss while also enabling customers to choose the right combination of inspection capabilities. The proprietary Simultaneous Transmitted And Reflected Light technology ‘STARlight2’ detects crystal growth and progressive defects on production photomasks. The new STARlight2+ (SL2+) algorithm improves on the STARlight inspection technology to enable 65nm and 45nm production as well as 32nm development. The advances provided by the SL2+ algorithm can be used across all of the system’s multiple pixel sizes, thus addressing a wide range of technology nodes, including enabling STARlight inspection on the smallest, most advanced 72nm pixel. This SL2+ algorithm technology finds both larger and smaller defects compared to its predecessor.  It also enables greater productivity through effective use of a larger pixel at an equivalent sensitivity, which is claimed by the company to cut inspection time nearly in half for a given application.  

Applications: Reticle inspection for logic and memory devices including single and multi-die configurations.

Platform: TeraFab SLQ-2X contains the completely new STARlight2+ algorithm and smallest pixels for highest sensitivity, to address the broadest array of applications in leading-edge fabs. It is equally applicable to IQC or mask re-qualification use cases and extendable to the sensitivity required for 32nm development.  TeraFab Q-3X is a specialized system for multiple-die re-qualification and incoming quality control (IQC) applications common to memory fabs, including Flash memory, while having good sensitivity and performance for fabs needing die-to-die coverage. TeraFab SLQ-1X offers the lowest cost of ownership (CoO) and highest ease of use (EOU) of the Terafab systems. The system handles single-die inspection typical of logic fab re-qualification applications, and operates at high throughput and low CoO.

Availability: February 2008 onwards.