FRT MicroSpy FT Budget-Friendly Optical Film Thickness Measurement

http://www.frtofamerica.com

The new MicroSpy® FT is a budget friendly single-sensor measuring tool for
2D and 3D thickness measurements of films that are transparent or semi-
transparent.

The tool is used in R&D as well as industrial production control. Main areas of
application are the measurement of coating thickness and complex film stacks
which are typical for products found in the medical, optical, photovoltaic,
semiconductor and MST industry.

The MicroSpy FT non-destructively measures coatings that transparent or
semi-transparent in the visible and near-infrared spectrum of light. The easy-
to-use film thickness measuring tool is cost-effective and powerful at the same
time. With its innovative 3D film thickness mapping mode, the tool allows the
thickness measurement of entire coating.

APPLICATION VERSATILITY:

For coatings that are transparent or semi-transparent in the visible or near-
infrared spectrum of light

For self-supported films (e.g. foils), single coatings or stacked films on a
substrate

For films as thin as 10 nanometers

2D point and profile measurements, 3D mapping mode

Sensors with different light sources, spot sizes and thickness measurement
ranges available

Basic automation functionalities

FAST AND INTUITIVE OPERATION

Integrated CCD-camera with illumination

Live camera picture of measuring area in software

Selection of measuring area with mouse

Easy to use evaluation software

Various functions for visualization, analysis and reporting
Powerful Hardware

Fast, non-contact optical sensor

Motorized x,y-measuring area of 50 mm x 50 mm

Manual sensor approach through precise z-axis

Depending on selected sensor, non-destructive film measurements of a few
mm down to 10 nm

The FRT MicroSpy® FT is designed to be cost-effective and powerful at the
same time.

PRINCIPLES

Reflectometric Measuring Principle

The optical reflectometric measurement principle bases on a superimposition of
light beams reflected at the boundaries of a thin film.

In contrast to the interferometric measurement, the measured reflectance
spectrum is compared with a calculated one, where the unknown thickness is
systematically varied until both spectra match. This allows to determine the
thickness of very thin films of a few nanometers.

Interferometric Measuring Principle

Light from a whitelight source (white LED, IR-LED) is focused onto the film. The
incident light is partially reflected at each boundary of a transparent film. The
recorded spectrum of the reflected light is evaluated to determine film
thickness.

Due to the interference of the light reflected at the boundaries of the layer, the
spectrum shows a typical waviness from which the sensor calculates the film
thickness. As the evaluated spectrum depends not only on the thickness, but
also on the refractive index of the material, the parameter is included in the
calculation of the thickness value.