Fast Spectroscopic Ellipsometer - ULVAC Technologies

Application Spotlight...
Fast Spectroscopic Ellipsometer
Ulvac has introduced two new high speed spectroscopic
ellipsometers for thickness and optical parameter
measurement of thin films on 200mm or 300mm
diameter wafers. Many spectroscopic ellipsometers
claim to be fast, yet still rely on rotating compensators
and electro optic modulators for signal measurement.
ULVAC’s, UNECS series instruments however employ a
novel new approach to deriving the physical constants
necessary to determine thin film thicknesses. Using a
white light source and a series of multi high order waveplates
in the optical path, the full spectrum carrying the
information about the wavelength-dependant parameters
of the reflected polarized light is generated and captured in
a single snapshot measurement. No mechanical or active
components for polarization control such as a rotating
compensator or electro optic modulator is required. The
signal is captured at the receiver end of the instrument by
a CCD based spectrophotometer in the form of a single
snapshot of the full spectrum from 530nm to 750nm. In
as little as 20ms, a high resolution measurement of film
thickness (0.1nm) can be made from the 4,000 data points
that are generated and analyzed in each snapshot.
(continued)
JULY / AUGUST 2012
ULVAC UNECS-3000 High Speed Spectroscopic
Ellipsometer for 300mm dia. substrates
Motorized R- 0– sample stage, showing the fixed 70° angle of
incidence of the optical path

It corresponds to the substrate size to
1100mm x 1400mm. The substrate can
be Load /Unload by MGV.
> Color Mapping of Film Thickness Distribution
News News
Break
a-Si/µc-Si Tandem Solar Cell Manufacturing Process
The 300mm diameter wafer moves automatically under the optical path via an R-0- stage. In addition, the
Z-height Substrate range (0 Substrate – 30mm) is ID adjusted TCO Laser automatically. Insulation Thanks Substrate to the PE-CVDhigh
speed PE-CVD measurement a-Si/µc-Si Laser of PVD the instrument,
Metal Laser
Loading Cleaning Marking Patterning Tester Cleaning System 1 System 2 Patterning System Patterning
and the high speed motion and compact design of this rotating sample stage, a high resolution film thickness
distribution map of a 300mm Laser Patterning wafer
can be performed (106 points) in as
little as 120s. Thickness maps can
Laser Patterning
Laser Patterning
be produced in X-Y or R-0- displays as
shown at right.
Metal Scribe
TCO Glass Substrate TCO Laser Scribe a-Si Deposition µc-Si Deposition a-Si/µc-Si
Laser Scribe
Backside
Electrode
• 3D Profiler
• 3D Profiler
• Stylus Profiler
• Ellipsometer
• Resistance
• Crystallization Rate
• 3D Profiler
• Stylus Profiler
• Resistance
> Compact Design
The size of the sensor unit is very
a function that can evaluate optical characteristics in addition to the conventional measurement of deposition
small due to the use of high order
thickness, surface shapes, and resistance.
wavelength plates. The built in light Color maps showing film thickness distribution across 300mm diameter wafers
source The MPEC-1300 and controller Multi-Probe are mounted Evaluation of Thin-Film Characterization System for tandem type solar cell
into has a the well following designed conventional compact enclosure. measuring The functions: CCD spectrophotometer (1) a “Surface Profiler,” is also which a very measures compact the component. deposition All
these thickness elements and help in-plane to make distributions the UNECS of electrode-use system smaller, thin less films; expensive, (2) a “Low-resistance and more reliable measurement,” than competitive which
instruments. evaluates the resistance distributions of electrode-use metal thin films. In addition, four additional measuring
functions have been intergraded including;
> (3) Built-in a “Raman Type Spectroscopy,” which maps in-plane distributions by
Because the components that make
obtaining µc-Si Crystallinity; (4) a “Three-dimensional (3D) measurement,” which three-dimensionally evaluates
up this ellipsometer are so small and
the shapes both of film surfaces after laser scribing and of TCO (Transparent Conductive Oxide) film surfaces;
compact, it’s possible to design this
(5) a “Spectroscopic Ellipsometer,” which evaluates the optical constants of a-Si thin films; and (6) a “High-
equipment directly into production
resistance measurement,” which evaluates the high-resistance distributions of a-Si thin films. By including a
tools for in-situ measurement of
total of six types of measuring functions, the MPEC-1300 Multi-Probe Evaluation of Thin-Film Characterization
thin film thickness or other optical
System for tandem type solar cell has enabled the thin-film characteristics evaluation of tandem type thin-film
properties.
solar cells to be performed in one system. The optical In addition, components since inside all surface the UNECS areas can of be a installed glass substrate directly into up other to the
The 5.5th-generation business end [the size components]
can be measured production with the tools system, for enabling there is in-situ, no need in-line to film destroy thickness substrates measurements.
for evaluation.
of These the optical excellent system features are very can easy greatly reduce initial introduction costs and running costs by about 1/2 com-
to pared locate to inside when other introducing instruments. two or Because more individual the measurement dedicated-use speed measuring of this unit instruments. is so fast and sensitive, this
ellipsometer has the potential to be used as a real-time feedback control instrument for film thickness and quality
control This evaluation purposes system in other is process designed tools such and that equipment. the user can Integrated select the metrology measuring using functions an ellipsometer to be included for real time
in-tool according film thickness to the user’s measurements purpose. ULVAC can provide is also significant developing advantages a system for and evaluating cost savings the distributions for manufacturers. of TCO
Haze and solar cell local conversion efficiency.
> The Demo newly and released Sampling MPEC-1300 Work tandem type thin-film solar cell hybrid thin-film characteristics evaluation
system will be available starting from June 24, 2009. For further information, please contact us.
ULVAC offers sampling of customer supplied substrates at our facility. Sampling data and a detailed discussion
of those results can be provided. And training is available at customer facilities or in our lab in Methuen, MA.
For Further Information, Please Contact Us...
Contact Us
• 3D Profiler
• Stylus Profiler
ULVAC Technologies, your total solutions provider