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Product Briefing Outline: Metara has introduced the ‘SENTRY' Harsh Chemistry Metrology (HCM) system that the company claims is the first of its kind to be able in fully automated mode to analyze harsh ultra-pure chemicals for metallic contamination excursions.


Problem: Leading edge IC's have imposed rigorous new purity standards on the harsh chemistries that are used in many processing tools. These chemistries include concentrated hydrofluoric, hydrochloric, sulfuric and phosphoric acids that are deployed in full strength or mixed with other chemicals for various etch and wafer-cleaning steps. Until recently, fab personnel relied on dispatching sporadic "grab samples" to analytical labs to test for purity. This manual, off-line approach dilutes the sample with ultra-pure water (UPW), which reduces the concentration of the potential contaminant, thereby making it much less sensitive to discovery. This approach is not only labor-intensive and subject to human error, but it is also slow and highly unreliable. Furthermore, it is inherently hazardous and often fails to detect serious contaminants in time to avoid a disastrous yield excursion.

Solution: Metara's automated HCM tool can operate with un-diluted chemistries by using a fully automated and sealed chemical extraction module (positioned 30m away) that draws chemistry directly from a process tool (s) tank into a proprietary ‘column' technology that neutralizes acid chemistries while reclaiming metals in the solution for analysis. With no need for dilution in UPW, accurate sampling is now possible.  Metara's proprietary In-line Mass Spectrometry (ILMS) technology, featuring an innovative electrospray time-of-flight mass spectrometer. This core engine has the ability to perform the sensitive, high-resolution measurement of anions and cations required for accurate process control and contamination detection. It is a proactive method that speedily determines the root cause and severity of a problem and allows for prompt corrective action before yield is threatened. The data is also made available in novel and customizable graphical form that allows engineers and technicians rather than highly skilled lab personnel to monitor for contaminants. Detection times of 40 minutes per sample are quoted by the company.

Applications: Chemistries include concentrated hydrofluoric, hydrochloric, sulfuric and phosphoric acids.

Platform: Based on the standard SENTRY platform the HCM tool uses a proprietary In-line Mass Spectrometry (ILMS) technology, featuring an innovative electrospray
time-of-flight mass spectrometer.

Availability: June 2006 onwards.