METHOD OF DETERMINING PLASMA ETCHING PARAMETERS Russian patent published in 2019 - IPC H01L21/3065 

FIELD: technological processes.

SUBSTANCE: method of determining parameters of plasma etching of materials during processing of articles involves measuring model sample parameters in form of a structure formed by first and second acoustic delay lines (ADL), ADLs comprise input and output electroacoustic transducers made on one face of a flat crystalline acoustic line, the other opposite face of which is open for plasma etching. ADL oscillation modes are selected on condition of providing differences in dependence of delay time on temperature and thickness of acoustic line so that first ADL has higher sensitivity to temperature and lower sensitivity to change of thickness of acoustic line in process of etching, and second ADL has lower sensitivity to temperature, but higher sensitivity to thickness variation of acoustic line during etching relative to first ADL. Required parameters of said etching are determined from the time dependence of the difference of the responses of the output converters when the excitation signal is applied to the input ADL transducers.

EFFECT: low level of threshold values and high accuracy of measuring parameters of plasma etching with automatic allowance for current temperature of the process.

8 cl, 6 dwg