Sandia`s plasma monitor detects defects

Albuquerque, NM

A software program used with a camera and peripheral equipment can detect plasma etched to the wrong depth on integrated circuits. The process developed by Sandia National Laboratories uses a camera to spectroscopically analyze optical emissions from plasmas as they etch printed circuit boards or silicon wafers. The programming allows near instant analyses of emitted wavelengths to detect if the plasma is misbehaving. “Plasmas have a fingerprint,” says Sandia scientist Pam Ward. “Our tool looks at that fingerprint, then compares it to the fingerprints of known failures. The pattern recognition is done by the laptop computer, which is part of the tool.” — LAK