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  Clean Room
 
 

It is a class 10000 clean room, with a surface of 50 m2. The clean room is available and being used for the preparation of thin molecular films in a dust fee environment, necessary for a flawless electronic characterization.
A globe box from mbraun allows the manipulation of oxygen and moisture sensitive materials. The molecular thermal evaporator and the metal thermal evaporator are located inside the globe box, making possible the deposition of reactive materials such as Li, K, Ba, Ca and Mg.


The clean room is shielded from UV radiation coming from illumination. This protects sensitive materials during the whole fabrication-measurement process.

 
  Chemical Characterization Techniques
 
 
Thermogravimetric and Differential Thermal Analyzer.
 
Model Mettler Toledo TGA/SDTA 851e that operates in the range 25 - 1100ºC with a sensibility of 0.1microg.
 
 
 
Differential Scaning Calorimeter.
 
Model Mettler Toledo DSC 821e operating in the range -150 - 500ºC equiped with a liquid nitrogen cryostat and a optic fiber option for photocalorimetry measurements.
 
 
 
High Performance Liquid Chromatography (HPLC) Basic.
 
High Performance Liquid Chromatography (HPLC) is a chemistry based tool for quantifying and analyzing mixtures of chemical compounds. It's used to find the amount of a chemical compound within a mixture of other chemicals. Dissolve the sample in a solvent (like water or alcohol), thus the term LIQUID chromatography. A detector measures response changes between the solvent itself, and the solvent & sample when passing through it. The electrical response is digitized and sent to a data system.
High Performance Liquid Chromatography (HPLC) is an analytical technique for the separation and determination of organic and inorganic solutes in any samples especially biological, pharmaceutical, food, environmental, industrial, etc. A chemical separation technique based on the differential distribution of the constituents of a mixture between two phases, one of which moves relative to the other. In a liquid chromatographic process a liquid permeates through a porous solid stationary phase and elutes the solutes into a flow-through detector.
There are three main types of chromatography, categorized by the mobile phase type: gas (GC), liquid (LC), supercritical fluid (SFC). The majority of the HPLC separations are done with Reversed Phase separation.
In Reversed-phase chromatography (RPC) separations organic molecules are separated based on their degree of hydrophobicity. There is a correlation between the degree of lipophylicity and retention in the column. Uses hydrophobic packings phases bonded to silica or neutral polymeric beads. Types of Detectors:
- UV - Ultraviolet light (Absorbance detector: waters 5487 with double λ)
- MS - Mass Spec (Electrospray is the ionization techniques) WATERS ZQ
*Source: Zspray
Under atmospheric pressure it has the ability to analyze polar molecules which could be positive or negative charged in solution.
Only for soluble samples.
*Mass analyzer: quadrupole
High reproducibility and resolution (∆m=0.01 uma)
*Molecular weight operating range, up to 4000(m/z)
 
 
 
Langmuir trough KSV 300
 
Computer controlled and user programmable Langmuir and Langmuir-Blodgett (LB) instrument for automated Langmuir film experiments and for unsupervised supervision of normal multilayers onto solid substrates.
LB technique is one of the most promising techniques to prepare thin films as it enables (1) a precise control of the monolayer thickness; (2) homogeneous deposition of the monolayer over large areas and (3) possibility to make multilayer structures with varying layer composition.
The first step for the preparation of a LB film is the spreading of an organic solution of an amphiphile on the water surface. As the solvent is evaporated a monolayer of the amphiphilic molecules is formed on the water surface. The monolayer is compressed with two barriers. This give rise to ordered 2D structures on the surface of water called Langmuir films. The Langmuir film is transferred onto a solid substrate by dipping the substrate up and down through the monolayer. After each dipping cycle two monolayers are transferred from the water surface to the substrate leading to multilayer thin films.
 
 
 
Langmuir trough Nima 702BAM
 
A large area computer controlled Langmuir trough equipped with a microbalance Measurement of the surface pressure of a monolayer film is achieved using the Wilhelmy plate technique with a resolution better than 0.1 mN/m. Pressure-area isotherms can be registered and, simultaneously, optically characterized by Brewster angle microscopy.
 
 
 
Potentiostat / Galvanostat Autolab PGSTAT 12
 
This is a potentiostat/galvanostat with a compliance voltage of 12 V, especially dedicated for research in solutions with low resistance, i.e. aqueous solutions. Maximum current is limited to 250 mA and current resolution is 30 fA on the 10 nA current range. It also offers the possibility to do iR compensation (both
i-Interrupt and Positive Feedback).
 
 
 
Electrochemical Quartz Crystal Microbalance (EQCM) CH Instruments, 400 Model.
 
The quartz crystal microbalance (QCM) is a variant of acoustic wave microsensors that are capable of ultrasensitive mass measurements. Under favorable conditions, a typical QCM can measure a mass change of 0.1-1 ng/cm2. QCM oscillates in a mechanically resonant shear mode under the influence of a high frequency AC electric field which is applied across the thickness of the crystal. QCM and the combination of QCM with electrochemistry (EQCM) have been widely employed for the determination of metals deposited onto the crystal, studies of ion-transport processes in polymer films, biosensor developments, and investigations of the kinetics of adsorption/desorption of adsorbate molecules. In EQCM experiments, the measurements of the various electrochemical parameters, such as potential, current and charge at the working electrode, and the acquisition of the corresponding frequency change, are conducted simultaneously.
 
 
 
Vertical laminar air flow cabinet.
 
Model V70 from Telstar
Air-filtered through two HEPA filters producing a class 1000 atmosphere. Spin coater is placed inside this cabinet, so the coat process is performed in an even cleaner atmosphere.
 
 
 
Spin coater, model KW-4a, Chemat technology.
 

Chemat Technologies model KW-4A is a compact spin coater for precise and uniform deposition of thin films and coatings.
It has a two stage spin process; this allows dispensing at low speeds and homogenizing the coating at high speed.
Stage 1:500-2,500 rpm (2-18 Seconds)
Stage 2: 1,000-8,000 rpm (3-60 Seconds)
Several sample chuck are available to hold substrates from sizes ranging from 5x5 to 30x30 mm2.

A SUSS Delta80 RC spin coater is also available. It is a semi-automatic system designed to coat wafers and substrates in size up to 150x150 mm2.
It has a programmable module to store multiple recipes. Acceleration and speed can be defined at different steps for each coating process. The coater has an automatic lid that covers the substrate and creates a solvent-saturated atmosphere; this allows the use of solvents with very high vapor pressure, like chloroform that, otherwise, would evaporate too fast resulting in inhomogeneous films.

 
 
 
  Physical Characterization Techniques
 
 
SQUID magnetometer , model Quantum Design MPMS-XL-5.
 
Operating in the range 1.7-400 K. Equiped with: AC/DC susceptibily and magnetization options by using applied fields up to +\- 5 T, RSO option (enhanced sensitivity), ultra low field option, single crystal mounting device with horizontal and vertical rotator and magneto-optical measurement option with LASER.
 
 
 
Physical properties measurement system.
 
Model Quantum Design PPMS-9, able to perform:
-AC/DC susceptibily and magnetization measurements by using applied fields up to
  +\- 9 T (1.9-400 K)
- AC/DC resistivity measurements by using applied fields up to +\- 9 T (0.35 - 400 K)
- Heat Capacity measurements by using applied fields up to +\- 9 T (0.35 - 400 K)
- Thermal transport measurements by using applied fields up to +\- 9 T (1.9 - 400 K)
- Torque magnetometry measurements by using applied fields up to +\- 9 T (1.9 - 400 K)
 
 
 
Profilometer Ambios XP1
 
An Ambios-Technology profilometer model XP-1, placed on a vibration isolation table.
Sample Stage Diameter:140mm
Scan Length Range: 30mm maximum
Sample Thickness: 20mm maximum
Vertical Resolution: 1Å at 10µm, 15Å at 100µm, 62Å at 400µm
Vertical Range: 400µm maximum
Magnification: 100X fixed objective with and attached CCD camera.
Stylus Tip Radius 2.0 microns
Stylus Force Range .05-10mg (programmable)
Scan Filtering Low-pass, high-pass, band-pass, and adjustable filter
The software performs calculation of surface roughness (Ra, Rq, Rp, Rv, Rt, Rz).
 
 
 
Layer by Layer
 
The KSVLMX2 system allows automatic preparation of mixed monolayers. This layer-by-layer instrument has vessel array of 3x16 units, and a three-clamp substrate holder, both of them home-buildt, making possible the preparation of three different samples simultaneously. This instrument is placed in the clean room, inside a cabinet in order to limit the evaporation of solvents.
 
 
 
X and Q band EPR spectrometer with additional Pulsed X-band .
 
Model Bruker ELEXYS E580
Oxford Instruments, operating in the range 4 -300 K with X and Q band sources equipped with crystal mounting options. Magnetic Fields 0-2 T ; 9.3 GHz / 34 GHz cavity and resonators.
The pulsed X-Band is equipped with a TWT amplifier. It is able to perform between 0.7 ns to 15 µs pulses width.
 
 
 
Kerr Magnetometer and Magneto-Transport
 
A Magneto-Optical Kerr Effect (MOKE) set-up allows to perform experiments in a temperature range between
(4-400) K.
The polarization light rotation induced by magnetic field could be measured in longitudinal and polar geometries. With applied magnetic field ranging up to+/- 380 mT in longitudinal and +/- 160 mT in polar configuration. In transverse geometry the magnetization give us information about the reflectivity changes of the samples. Magneto-Transport measurements at the surface by using applied fields up to +/- 380 mT and (4-400) K.
 
 
 
Mossbauer Spectrometer
 
ARS (Advanced Research Systems) Helium Closed Cycle Mossbauer Cryostat (Operating Temperature Range between 8 to 355 K).
?-Rays are provided by a57Co(Rh) source.
 
 
 
X-Ray Diffractometer
 
Oxford Diffraction Gemini S Ultra diffractometer.
Mo and Cu co-mounted Enhance X-ray source
Sapphire CCD detector
Four circle Kappa Geometry X-ray Goniometer
Cryojet temperature controller (Operating Temperature Range between 100 to 400 K).
 
 
 
Multimode Scanning Probe Microscope Manufacturer/model: Veeco Nanoscope IVa
 
Description: The microscope operates in air at room temperature, in STM, AFM or MFM modes. Equipped with 1 STM head and 1 AFM/MFM head running with the same electronics, it provides images with molecular resolution with scanning lateral range (x-y) of 15µm x 15µm and vertical range (z) of 2.5µm. Suited for single-molecule investigations as well as high-resolution spatial characterization of molecular monolayers.
 
 
 
Brewster angle microscope.
 
EP3-BAM from nanofilm is composed of a laser with wavelength 532nm, polarizers, shutter, 10x objective with focus scanner, analyzer, and CCD camera.
Precise control of the angle and work height is achieved with computer controlled software.
The whole setup is assembled inside a closed cabinet. The Nima Langmuir trough is used to study the morphology of monolayers at different surface pressures with different subphase composition with a lateral resolution of 500 nm.
 
 
 
Molecular thermal evaporation.
 
A vacuum chamber placed inside the glove box can achieve high vacuum, at pressures bellow 10-6mbar. Equipped with a water-cooled turbo molecular pump. And 6 individual pockets allow co-evaporation of different materials. Two water-cooled optical sensors are used to measure the rate of material evaporation with a 1Å resolution
 
 
 
Metals thermal evaporator.
 
A vacuum chamber placed inside the globe box can achieve high vacuum, at pressures bellow 10-6mbar. Is used for the thermal evaporation of metals (Al, Ba, Ca, Ag, Au) and other compounds (LiF, Cs2CO3) onto the surface of solids substrates.
Mainly used for the preparation of the anode/cathode on OLEDs and solar cells. Is a very precise tool for the evaporation of materials with high sublimation temperature.
Thickness is monitored with an Edwards FTM7 film thickness monitor.
 
 
 
Solar simulation equipement.
 
A sun simulator from ECN (Energy research Centre of the Netherlands), is used to obtain the characteristic IV curves of solar cells. Measurements are done in 4-wire configuration.
 
 
 
Measure equipment.
 
Several instruments are used to measure and characterize devices produced in the lab.
Keithley source meters and picoampmeters with Si photodiode detector, allows a very precise way to measure light emitting devices.
A four channel oscilloscope, Tecktronix TB2024B.
A multichannel modular remote-controlled system for the signal generation and simultaneous measure of data through 16 channels.
In-house developed software is used for the control of these electronic devices.
A Potentiostat / Galvanostat Autolab PGSTAT 12 with a compliance voltage of 12 V, especially dedicated for research in solutions with low resistance, i.e. aqueous solutions. Maximum current is limited to 250 mA and current resolution is 30 fA on the 10 nA current range. It also offers the possibility to do iR compensation (both
i-Interrupt and Positive Feedback).