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Product Briefing Outline: Novellus Systems has launched two specific dry strip and clean systems that each target different photoresist removal requirements for leading-edge logic and memory manufacturing. The ‘G400’ is designed for large volume, high-throughput requirements of bulk and high-dose implant strip (HDIS) applications in DRAM and flash memory fabs. The ‘GxT’ is designed for HDIS, super-HDIS and BEOL clean applications, where low silicon loss and ultra-low defect levels are required in advanced logic applications. The ‘G400’ and ‘GxT’ are built upon Novellus’ high-throughput ‘GAMMA’ platform. Both systems have shipped to customers, with the first G400 going to a large Asian memory manufacturer and the GxT placed at multiple large foundries in Asia, according to Novellus.

Problem: With IC manufacturing becoming more complex, there is a clear need for specialized, dedicated tools that have been optimized to meet diverging processing needs. Strip systems in cost-sensitive memory applications need to deliver the highest levels of productivity while providing the lowest cost of ownership. Logic applications, on the other hand, are driven by advanced technology requirements, with a need to deliver low silicon loss, ultra-low defectivity and critical clean applications.

Solution: Targeting bulk strip and high-dose implant stripapplications primarily used in large DRAM and flash memory fabs, the G400 is the industry’s highest throughput ashing system. Enhanced source technology combined with faster wafer heating for higher ash rates enables the system to simultaneously deliver over 400 wafers per hour for bulk strip applications and more than 300 wafers per hour for implant strip applications. The multi-station sequential processing (MSSP) chamber design can achieve processing times of between 5-6 seconds due to its ability to continuously operate the RF plasma, which actually ashes during chamber-to-chamber transportation. The G400 combines a new high-rate ashing technology with an optimized system design to provide up to a 25 percent productivity gain compared to prevailing industry standards. The GxT takes advantage of Novellus’ production-proven multi-station sequential processing architecture, offering multiple process zones that provide the flexibility to handle complex recipes and chemistries. The system’s SmartFlow gas distribution technology supports individual station-by-station control of both oxidizing and reducing chemistries

Applications: G400: high productivity memory fabs. GxT: advanced logic applications.

Platform: Built on the GAMMA platform, a key to the system’s success is its ability to support higher-temperature bulk applications, lower-temperature HDIS and advanced cleaning processes simultaneously on the same platform. These lower-temperature applications are integral to providing low silicon loss while ensuring high throughput (300wph) with a low cost of ownership.

Availability: May 2008 onwards.