Equipment of Optoelectronic Phenomena and Materials

Research People Equipment Publications

Preparation of thin organic films, multilayered sandwich films of various organic materials and metals deposited in vacuum; the film thickness controlled with a quartz crystal. Spin-coating, dip-coating or spray-coating of polymer films from polymer solutions. Preparation and complex characterization by various techniques, incl. cyclovoltammetry, spectroelectro-chemistry optical absorption, photoluminescence, electroluminescence, photovoltaic characteristics, photoconductivity in various time-scales - from ns to cw, in an inert atmosphere.

  • Instrument:
  • A glow box system consisting of two independent interconnected glove boxes and one separate glovebox with built-in euipment for electrical and optical characterization , spin-coater, dip-coating, spray-coater, vacuum deposition facility, quartz crystal balance monitor, profilometer

 


Transient optical absorption spectroscopy of solutions and thin films with time resolution of 40 fs suitable for studying kinetics of photoinduced phenomena, particularly of processes after photoexcitation of molecules: internal conversion, intramolecular vibrational relaxation processes, charge and energy transfer. Such processes are important for polymer photodegradation and for polymer solar cells. The system is designed as modular, suitable also for other optical experiments, like nonlinear optical measurements..

  • Instrument:
  • Pump-probe transient absorption spectrometer HELIOS (Ultrafast Systems). The pump laser pulses are generated by a cascade of lasers consisting of the primary oscillator Mantis, regenerative amplifier Legend Elite, and TOPAS-C optical parametric amplifier (all devices from Coherent) completed with a dichroic separator at the end of the beam line. The system generates laser pulses of tunable central wavelength  (full width at half maximum, FWHM,  8 nm) at the repetition rate 1 kHz.



Electrical impedance measurements for determination of electrical conductivity and electrical permittivity of powder samples, polymer films and layers in a wide range of temperatures (100 K – 500 K) and frequencies (10-3 – 109 Hz). The device offers also the possibility of broadband dielectric spectroscopy measurements for the determination of relaxation properties of polymers.

  • Instrument:
  • Broad band dielectric spectrometer Novocontrol equipped with Alpha A analyzer (frequency range 1 mHz to 10 MHz) and Agilent E4991 RF impedance analyzer (frequency range 1MHz to 3 GHz).


 

Charge carrier mobility measurements of semiconducting materials using TOF, CELIV and OFET methods., post-transit behaviour, space-charge and trapping effects, and quantum efficiency of photogeneration of free charge carriers in polymer films by transient photocurrent measurements (time-of-flight method) with nanosecond time resolution.

  • Instruments:
  • Nd YAG and dye laser ND-60 Continuum Corp. with doublers - pulse duration 3-5 ns, wavelength regions 550-740 nm and 270-370 nm, 1-5 mJ per pulse in UV region, about 30 mJ per pulse in the visible region, 200 mJ at 532 nm, 450 mJ at 1064 nm, 10 Hz repetition rate or single pulse capacity.
  • Digitizing oscilloscope Hewlet-Packard 5410 B.


 

DC and AC electrical characteristics in the dark and under illumination in the temperature interval 10 - 400 K. Photoelectrical characteristics in the spectral range 200 - 800 nm. Measurements of photogeneration efficiency of high-resistivity films by the xerographic discharge method. Thin film transistor and solar cell characterization. Four-point measurements of electrical conductivity of conductive materials in a form of pressed pellets (va der Powe method) and thin films (liear four probe method is included.

  • Instrument:
  • Variable sets of instruments (Keithley electrometers and stabilized power supply, xenon lamp, 0.25 m monochromator Jobin Yvon, radiometers EG & G 580, closed cycle helium refrigerator Displex Air Products with vacuum system).

 


 

Characterization of photochromic and electroluminescent behaviour of organic solids including time resolution (in millisecond time resolution) and temperature dependences.

  • Instrument:
  • UV-VIS spectrometers equipped with high sensitivity detector head EG & G 585 and temperature controller (Haake H40/F6), self-made spectrometer for thermostimulated absorption.


Preparation of nanoparticles by laser ablation, laser microfabrication.

  • Instrument:
  • Nd YAG laser and femtosecond laser setups (see TOF and transient absorption methods above).

BIOpolymer POstdoctoral Laboratory and educational center - BIOPOL

Otto Wichterle Centre of Polymer Materials and Technologies - CPMTOW

Centre of Biomedicinal Polymers - CBMP

Centre of Polymer Sensors - CPS

Polymers for Power Engineering - Energolab


 

Institute of Macromolecular Chemistry AS CR, v.v.i.
Heyrovského nám. 2
CZ-162 06 Praha 6
Czech Republic
phone:+420 296 809 111
fax:+420 296 809 410

Strategie 21