LeakDefender™ Thermocouples

Real-time gas monitoring to minimize wafer loss and maximize thermocouple life

Hydrogen gas leaking through the quartz thermocouple sheath is an early-warning sign to stop and change a thermocouple before more costly damage occurs; or safety of personnel, equipment or product is compromised. These leaks can lead to:

• Operator safety concerns resulting from process gases leaking out and atmosphere leaking in
• Wafer yield loss due to surface defects
• Damage to the tool that can lead to premature chamber change and potential tool explosion
• Costly unscheduled tool downtime

Conax Technologies’ new LeakDefender™ brand thermocouples are used to monitor the quartz sheaths for gas leaks in real time and allow for fast shut down of the reactor. This minimizes or completely eliminates wafer yield loss!

LeakDefender™ Brand Thermocouple benefits

• Lower tool Cost of Ownership (CoO): Real-time leak detection ensures faster leak discovery, limiting loss to a single wafer.
• Improved yield: Surface defects caused by leaks are reduced to minimize scrap wafers.
• Reduced process variation: Atmospheric leaks that cause excessive chamber coating and power disruption are prevented, reducing the need for adjustments to power offsets.
• Reduction in unscheduled downtime: Early detection of atmospheric leaks prevents premature chamber cleans.
• Increased tool and cleanroom safety: Localized leak detection occurs earlier than with cleanroom H2 detectors, preventing hydrogen chloride leaks from corroding external hardware.
• Seamless integration with system controller: Thermocouples connect directly to OEM-provided user digital input.
• Proven technology: Hydrogen gas detectors are widely used in epitaxial reactor H2 monitoring systems.
• One-shift installation: The 6-hour installation and 2-hour calibration and testing can be completed in a single day.
• Cost-effective protection: The cost is less than a single scrapped device wafer, and off-the-shelf components eliminate the need for special equipment.
• Center TC monitoring: The center TC is most prone to premature sheath failure. The LeakDefender™ Brand Center TC monitoring line leaves the rotating assembly through a special slip ring assembly.

How it works
 
Depending on process chamber type, a typical reactor has two or three LeakDefender™ thermocouples installed in the horizontal orientation and one LeakDefender™ center thermocouple installed in the vertical orientation.

Gas monitoring lines exit each of the LeakDefender™ thermocouples and are routed into the TC Sentry System™ gas monitor. If a premature thermocouple sheath breach condition occurs, this in-situ monitoring system will detect the leak and prevent product loss and major unplanned maintenance events. The TC Sentry System™ gas monitor is manufactured by Helios Technical Services. This system is capable of detecting minute volumes of hydrogen and triggering one or more control outputs. The ultra-fast detection and response of the system will prevent product loss and contamination of items internal to the process chamber. Detecting a single premature thermocouple sheath failure can save significant time and money.