Camera Endpoint Monitor based on Real Time Laser Interferometry
LEM Series - HORIBA, Ltd.
Our Real Time Interferometric Process Monitor provides high precision detection of film thickness and trench depth during the etching/deposition process.
Depending on applications, LEM camera includes a 670 or 905 or 980 nm laser and when mounted on any dry etch/deposition process chamber with a direct top view of the wafer this generates a small laser spot on the sample surface.
Interference occurs when monochromatic light hits the sample surface, resulting in different optical path lengths due to film thickness and height variations in the film.
This allows the etch/deposition rate and thus thickness to be monitored in real time, also fringes counting or more complex analysis, providing enhanced process control Endpoint for a wide variety of processes. Additionally interfaces can be detected by their change in reflectivity.
