Real-time plasma monitoring technique using incident-angle-dependent optical emission spectroscopy for computer-integrated manufacturing

Although various monitoring techniques are currently used for semiconductor manufacturing, OES is a non-contact and non-destructive plasma measurement tool that detects end points and plasma abnormality. Despite these advantages and their high utilization in plasma processing measurement, the acquisition region of OES data at various wafer sizes only allows examination of part of the plasma, owing to the characteristics of the conventional OES resulting in the limited detection capability of process abnormality. In this paper, a novel real-time monitoring method for detecting plasma process uniformity and abnormality using incident-angle-dependent OES is proposed. Using both a body tube and a wide-angle lens to adjust the incident angle of OES, the intensity of plasma light can be measured accurately using selective plasma light in semiconductor manufacturing. This real-time monitoring technique can be utilized to obtain plasma light in a process chamber and thereby analyze the uniformity and detect the abnormalities in the plasma process for computer-integrated manufacturing.