REAL-TIME GATE ETCH CRITICAL DIMENSION CONTROL BY OXYGEN MONITORING

摘要

A method of controlling a gate etching CD(Critical Dimension) in real time using oxygen monitoring is provided to perform simply repeatedly a trimming process on a gate regardless of the influence of a plurality of variables by controlling exactly the concentration of an etching gas using a mass flowmeter. An aiming etching gas concentration is measured. An inert gas is supplied into an etching chamber(50). A first signal for showing a real etching gas concentration is generated. A second signal for showing an inert gas concentration is generated. A standard etching gas concentration is generated by using the first and second signals. The standard etching gas concentration is compared with the aiming etching gas concentration. A mass flowmeter(54) is controlled according to the result of comparison.