TFA Thin Film Analyzer

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Thin Film Analyzer

LINSEIS Thin Film Analyzer (TFA)

The LINSEIS Thin Film Analyzer is the perfect solution to characterize a

broad range of thin film samples in a very comfortable and quick way.

It is an easy to use, single stand alone system and delivers high quality

results using an optimized measurement design as well as the proven

LINSEIS Firmware and Software package.

The big advantage of this system is the simultaneous determination

of all interesting physical properties within one measurement run at

one sample. Therefore all measured results are very comparable and

errors due to different environmental conditions like sample geometry,

composition or heat profile can be avoided. Another big advantage is

the modular System design. If you only want to measure a part of the

possible properties, you can start with a basic device and upgrade your

system later if necessary.

The System can also handle a very broad range of different materials.

It is possible to measure samples with metallic behavior as well as

ceramics or organics. Therefore many different deposition methods like

PVD, CVD or Spin coating are possible to use.

Motivation

The characterization of the thermal properties of thin film materials

is important both for understanding of their structure and conduction

mechanisms and for their technical applications.

LINSEIS TFA

The TFA has been developed to reach highest demands on

measurement requirements in a Temperature range from -150°C up to

400°C. Samples can be measured under the influence of a very strong

magnetic field up to ±1 Tesla.

Measurement Setup

The measurements are taken using the very well known Van-der-Pauw

Method and the 3w hot strip technique.

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Components

The basic setup consists of a measurement chip on which the sam-

ple can be easily deposited and the measurement chamber to provide

the required environmental conditions. Depending on the application,

the setup can be utilized with a Lock-In amplifier and / or a strong

electric magnet. The measurements are usually taken under UHV and

the samples temperature can be controlled between 150 K and 700 K

during the measurement using LN2 and powerful heaters. Because of

the symmetric and thermally optimized design, it is also possible to

apply variable temperature gradients.

Modular design

Due to the unique optimized design of the system, different chips like

the “Lambda”, “Sigma“ or the “ZT” Chip can be used. As there are

many different applications, it is also possible to create and use custom

designed chips, to adapt customer requirements to the existing layout.

Starting with a basic setup to measure, the System can be upgraded

easily with either the transient upgrade kit to measure the thermal

conductivity and specific heat with the 3w Method or the magnetic

upgrade kit to take Hall constant, mobility and charge carrier concen-

tration measurements.

Packaging options

Following packaging options are available for the LINSEIS Thin Film

Analyzer (TFA):

1. Basic device:

Consists of measurement chamber, vacuum pump, basic sample hol-

der with included heater, measurement electronics, PC and LINSEIS

Software package. The design is optimized to measure following phy-

sical properties:

• l - Thermal Conductivity (steady state / in plane)

• r - Electrical Resistivity

• s - Electrical Conductivity

• S - Seebeck Coefficient

• e - Emissivity

2. Transient package:

Consisting of system integrated lock-in amplifier, electronics and eva-

luation software for 3w- method. The design is optimized for measu-

ring the following parameters:

• l - Thermal Conductivity (transient / in plane and cross plane)

• cp - Specific Heat

3. Magnetic package:

Selection of integrated electrical magnet, depending on application

requirements.

The design is optimized for measuring the following parameters:

• AH - Hall Constant

• μ - Mobility

• n - Charge carrier concentration

4. Low temperature option for controlled cooling down to 100 K

• TFA/KREG controlled cooling unit

• TFA/KRYO Dewar 25l

Measuring setup Packaging options

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Measuring principles

1. Van-der-Pauw Method

The sample with a defi ned geometry gets connected by four elec-

trodes. A current is applied between two of the contacts and the voltage

between the remaining two is measured.

The same procedure is done clockwise for other constellations and

using the Van-der-Pauw equation, the resistivity of the sample can be

calculated very exactly. By applying a magnetic fi eld and measuring

the change of the Van-der-Pauw resistivity, the Hall coeffi cient of the

sample can be measured using the same setup.

The sample size is approx. 25 mm² and the possible specifi c resistivity

to measure is from 0.1Ω up to 100 MΩ.

With additional thermometers near the contacts, the Seebeck coeffi ci-

ent can be measured in different directions at the same sample.

S – Seebeck Coeffi cient

2. Hot stripe measurement

The sample is deposited on the bottom side of a very thin Membrane.

A very samll wire is deposited on the topside of this Membrane. For the

measurement, a current is applied to the hotwire which is heated up

due to Joule heating. Because of the temperature rise, the resistivity of

the wire is changing and can be measured easily. From this resistivity

change, it is possible to calculate back to the thermal conductivity of

the sample. This setup can be used either with a DC or AC (3w) current.

Depending on the used method it is also possible to measure the emis-

sivity and specifi c heat of the sample.

To measeure high quality results, the sample thickness times sample

thermal conductivity must be equal or bigger than 2 x 10E-7 W/K.

Membrane (λMdM)

Sample (λSdS)

Si Si

Hot Wire

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Thermal conductivity measurement (DC)

Thermal conductivity of a Bi0.9Sb0.1 film with a thickness of 100nm as function of temperature.

Measurements

λla

yer[W

/(m

•K)]

6

5

4

3

2

1

0

T0 [K]260 270 280 290 300 310 320 330 340 350

Specific heat measurement (AC – 3w)

Specific heat capacity of a 30nm thin Ag film as function of temperature between 80 and 300K.

cp[

J/(c

m3 •

K)]

3.0

2.5

2.0

1.5

1.0

0.5

0

T0 [K]50 75 100 125 150 175 200 225 250 275

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Thermal conductivity measurement (DC & AC)

Thermal conductivity of an 800nm thin SiO2 / Si3N4 sandwich, measured with the steady state (red) and the transient (blue) technique in the temperature

range 80-300K.

λ[W

/(m

•K)]

3.0

2.5

2.0

1.5

1.0

0.5

0

T0 [K]50 75 100 125 150 175 200 225 250 275

steady-state

transient

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Thermoelectric devices

A typical application is the characterization of thin films made out of

thermoelectric materials. A lot of research is done to improve the effi-

ciency of thermoelectric devices.

Integrated devices

For the development and design of new and robust integrated devices

like sensors or microchips, the semiconducting industry needs to know

a lot about the physical properties of the used films. For example for

the heat management or the electric insolation of such devices.

Thermal barrier coatings

Another interesting field for thin films are thermal barrier coatings as

they are used in aircraft engines. Many new materials have been deve-

loped and characterized, especially in regard to their thermal behavior.

Tribological stress

The last application example is the determination of material parame-

ters for thin films used in tools. The understanding is very important

to avoid wear due to tribological stress to ensure an extended product

life cycle.

Applications

LINSEIS GmbHVielitzerstr. 43

95100 SelbGermany

Tel.: (+49) 9287–880 - 0Fax: (+49) 9287–70488E-mail: info@linseis.de

LINSEIS Inc.109 North Gold DriveRobbinsville, NJ 08691USATel.: +01 (609) 223 2070Fax: +01 (609) 223 2074E-mail: info@linseis.com

www.linseis.com

Products: DIL, TG, STA, DSC, HDSC, DTA, TMA, MS/FTIR, In-Situ EGA, Laser Flash, Seebeck Effect Services: Service Lab, Calibration Service