Instrument Design

The Auto SE spectroscopic ellipsometer is of phase modulated design, and uses 4 liquid crystal modulators to modulate and analyse the polarisation of the incident and reflected light beams.

The Auto SE phase modulated ellipsometer has no moving parts during signal acquisition, allowing very high measurement precision and no beam rotation.

This can be very important when measuring very thin and / or highly transparent films.

Data Acquisition System

The Auto SE phase modulated ellipsometer has a fully digital signal acquisition system.

This method of measurement is far removed from electrical mains frequencies and mechanical vibrations, and the MM-16 phase modulated ellipsometer may make measurements in environments that would be difficult for rotating type ellipsometers using analogue signal averaging.

Each LCM is switched between 0º and 45º within each scan, with 16 measurements made per scan. The full polarisation state of the sample is measured with very high accuracy.

By using a CCD with 2048 pixels the Auto SE  can acquire ellipsometric data across the full spectral range within 2s

Spectral Range

450 - 1000nm

Light Source

Combination halogen lamp and blue LED

Ellipsometer Heads

The two ellipsometer heads are identical and are configured as:

Polariser - LC modulator – Quarter Wave Plate - LC modulator.

This configuration allows the Auto SE to generate and analyze all possible polarisation states of the sample

Optical System

The Auto SE includes a very high light throughput optical system for very low spectral background across the wavelength range. The grating and detector are optimised to provide high optical performance without any gaps in coverage or performance.

·         Spectrograph Focal length : 70 mm

·         Resolution: 1.5 nm

·         Linear CCD  2048 pixels

·         Integration time : from 2 sec to 10 sec

Control Electronics

Intelligent high speed electronics including :

·         Liquid Crystal Drives

·         Fast data acquisition module

·         PIO control of filter, shutter and trigger

·         Computer interface

·         Diagnostic routines

Goniometer

The angle of incidence is 70°.

Sample Holder

Square Sample holder : 200mm X 200mm

Reference samples SiO₂ and Aluminium attached for automatic validation of the measurement

Protection of reference samples

Compatible with all accessories

Vacuum chuck

Sample Stage

Automatic  X-Y-Z stage

Maximum stroke 200 x 200 mm

Maximum thickness of the sample : 50 mm

Automatic Z adjustment by reflected intensity

Vision Capabilities

2D Colour CCD sensor for MyAutoView vision system : 752 X 576 pixels

·         Brightness and contrast driven by software

Microspots

·         Motorised Microspots with  8 different spot sizes :

o    Rectangular shapes

§  25µm X 60µm¹

§  50µm X 60µm¹

§  70µm X 250µm¹

§  250µm X 500 µm

o    Square shapes

§  100µm X 100µm

§  250µm X 250µm

§  500µm X 500µm

¹ Requires optional high intensity Xe arc source.

Calibration

Automatic calibration procedure by using the attached reference samples

Data Acquisition

•          Typical acquisition time : 5 sec

•          Minimum acquisition time : 2 sec 

Software

The Auto SE is controlled by the Auto Soft software that controls all HORIBA Jobin Yvon ellipsometers.

Auto Soft is Multilanguage software which integrates very intuitive interfaces based on the use of icons and internet like hyperlink navigation.

The software fits the needs of three types of user :

- OPERATOR using a simple interface for routine thin film control

- ENGINEER with a large variety of analysis functions to optimize results and/or experimental recipes.

- SERVICE with an interface for detection and diagnostic of possible problems with the system.

Auto Soft integrates a large database of applications. Recipes are available for microelectronics, displays, photovoltaics, optical coatings, biotechnology as well as many other thin film applications. These families of Experimental Recipes allow the fully automated analysis of thin film samples with single push button operation.

The sample analysis takes only a few seconds and provides a complete report that fully describes the thin film stack – including film thicknesses, optical constants (n,k), surface roughness and film inhomogeneities.

Users can easily customize the family classification as well as expand the recipe database.

Accuracy

NIST 1000Å SiO₂/Si

Thickness : ± 4 Å

n (632.8nm) : ± 0.002