Resonant Frequency Shift as Etch Stop of Gate Oxide of MOSFET Transistor

Abstract: an etch process performed during semiconductor processing is monitored using a resonant structure on a surface of a wafer, formed on the surface of a wafer as a resonant cavity. a resonance sensor is positioned over the wafer within a plasma etch chamber so as to establish a resonance with the resonant structure. a resonant frequency of the resonant structure is sensed through the resonant structure and shifts in the resonant frequency are thereby detected during an etch process as a measurement of the etch process. the etch process is controlled in accordance with the shift in the resonant frequency.

Inventor(s): HESHAM MOHAMMED ENSHASY

CPC Classification: H01J37/32963 (Gas-filled discharge tubes (heating by discharge ))

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