About us

Summary

Group activity

The group of Thin Films for Photovoltaic Applications is oriented towards depositions and nano-scale characterization of thin semiconducting films or selective contact used for photovoltaic purposes. Our aim is to probe alternative promising concepts and at the same time study the state of art materials and its properties with high spatial resolution.
In the last years, the main attention of this group was focused on four topics:

  1. Thin silicon based films used for passivation and as selective contact layers in heterojunction solar cells, in a frame of EU Horizont 2020 project NextBase
  2. Shallow doping (<10 nm) of the silicon surface by laser ablation or Schottky barrier on self-assembled carborane molecule monolayers.
  3. Halide perovskites for photovoltaic applications
One of the group laboratories - laboratory of Raman Spectroscopy with two Renishaw inVia Reflex spectrometers and possibility of measuring in a glove box with nitrogen atmosphere.
Description

One of the group laboratories - laboratory of Raman Spectroscopy with two Renishaw inVia Reflex spectrometers and possibility of measuring in a glove box with nitrogen atmosphere.

 

 

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 Research Areas

Study of opto-electronic properties of hybrid organic–inorganic halide perovskite

Solid State Physics and Magnetism (BM)

In collaboration with our partners (Institute of Microtechnique (IMT) PV-LAB, EPFL Neuchatel, Switzerland or KAUST Solar Center, Thuwal, Saudi Arabia) in the Laboratory of Raman spectroscopy are studied the opto-electronic properties of thin films of hybrid organic–inorganic halide perovskite. Emphasis is on the studying of material quality using absorption spectra. For this purpose, not only methods available in the laboratory (photoluminescence and Raman spectroscopy and atomic force microscopy), but also other devices within the Institute of Physics of the Czech Academy of Sciences are used. The main objective is to study defect states. These have a significant impact on the function and efficiency of photovoltaic cells or other optoelectronic devices.

Example of perovskite structure of the most studied hybrid organo-metallic perovskite - CH3NH3PbI3.
Description

Example of perovskite structure of the most studied hybrid organo-metallic perovskite - CH3NH3PbI3.

The silicon thin films thickness imaging using photoluminescence spectroscopy 

Solid State Physics and Magnetism (BM)

Thin films of amorphous silicon are now used for the passivation of the silicon solar cells’ surface. Due to higher energy conversion efficiency these so-called heterostructure solar cells are likely to become the main technology in photovoltaics by the year 2030. To further increase the efficiency, it is necessary to avoid losses caused by shielding by the front contacts. We can transfer both contacts to the back of the cell, creating interdigital contacts. That means stacking thin layers of amorphous silicon. From a practical point of view, the structuring by masks applied to the cell during deposition of the amorphous layer proves useful. It is important to verify the shape and properties of the deposited structure. Optical profilometry imaging and direct imaging of these layers is a topic that we solved during the EU 2020 H NextBase project. This method has been identified as a significant outcome of the project and we continue its improvement.

Imaging of thin strips of amorphous silicon on the surface of a crystalline silicon plate by photoluminescence.
Description

Imaging of thin strips of amorphous silicon on the surface of a crystalline silicon plate by photoluminescence.