Process Probe 1840 RTD Instrumented Wafers

SensArray Announces New Longer-Life, High-Reliability Instrumented Wafers for Lithography Track Temperature Measurements In Situ

June 24, 1999, Santa Clara, Calif.—SensArray Corporation, a provider of innovative temperature metrology solutions for semiconductor, LCD, and memory disk fabrication processes, today announced its new longer-life, higher-reliability Process Probe 1840 RTD instrumented wafers. The revised wafer offers improved flat cable feedthrough flexibility, lead system, and temperature-tolerance bonding and insulation materials. 1840 wafers provide direct, high-accuracy multipoint wafer temperature measurement, in situ, using up to 31 resistance temperature detectors embedded in the wafers. The instrumented wafers are used to monitor temperature with accuracy greater than 0.1°C in photoresist track, wafer prober, and other semiconductor fabrication equipment. The operating temperature has increased to 250°C; sensor-to-sensor precision has improved by a factor of two, and is now ± 0.03°C.
The 1840 features a unique embedded sensor bond design that provides high-accuracy and measurement repeatability with minimal hysteresis and thermal conduction errors. The new design significantly improves product longevity, reliability, flexibility, and operational convenience. New advances include:

• Redesign of the flat cable feedthrough assembly to be more compact, flexible, and durable. The width has been reduced from three inches to just over a ½ inch for a 17-sensor wafer, and nickel ribbons border the cable to prevent compression damage when the cable is clamped under a vacuum flange or seal.
  
• A new lead stress-relief assembly, with a Kevlar tensile element, to prevent the cables from stretching or breaking under tension.
  
• Replacement of the semi-rigid Teflon with ultra-flexible silicone sleeving for the leads between the flat cable and the connector to improve convenience in placement and ease of handling.
  
• Replacement of the bonding and insulating materials with polyimide for improved tolerance to thermal stress.

Process Probe 1840 wafers are used for equipment characterization, process development, and process monitoring. They enable accurate multipoint direct wafer temperature measurement and reduce the consumption of monitor wafers. The 1840 can be paired with SensArray's sophisticated data logging, analysis, and graphical display engineering tools, Thermal TRACK and Thermal MAP. This allows evaluating across-wafer temperature nonuniformity and changes over time during a thermal cycle. The wafers are available in 100 mm to 300 mm wafer diameters and can be factory-calibrated to NIST-traceable temperature standards.

SensArray Corporation, 3410 Garrett Drive, Santa Clara, CA 95054. Tel: 408-330-5600; Fax: 408-330-5601.