Research methods of the absorbing surface of solar elements

Abstract

The article considers and analyzes the main requirements for thin-film solar elements,
namely the presence of a base layer with a high absorption coefficient of optical radiation; an
appropriate wide-gap layer, which is required in the formation of a heterojunction; ensuring
efficient collection of charges by electrical conjugation of layers; reliability of ohmic contacts.
The main difficulties associated with the production of thin films are identified, both
theoretical and practical, namely grain boundaries affect recombination, current transfer, diffusion
and segregation; there is a problem of contact phenomena for structures of several materials due to
the need for electrical coupling of different layers of the solar element; point defects in thin-film
solar elements are not well understood.
It is determined that when manufacturing solar elements, it is important to evaluate the
quality of each of its layers at the deposition stage in order to realistically represent their crystal
structure, chemical composition, optical and electrical properties.
It is noted that during long-term operation of solar panels and solar batteries, there is a
significant decrease in their performance, due to the deterioration of the main parameters, which are
efficiency and output power.
It is proposed to consider the study of physical processes in the structure of the
semiconductor layer of a solar element, as well as the study of the physical properties of thin films
for a solar element, based on the following main research methods: scanning probe (capacitive) and
tunneling microscopy (spectroscopy); atomic force microscopy; fluoroscopy; electronic
microanalysis; scanning electron microscopy; ellipsometry; spectroscopic ellipsometry; Auger
electron spectroscopy; mass spectrometry of secondary ions; photoluminescence; scanning laser
microscopy.
It also shows the possibility of using a number of optical, electrical, X-ray and other studies
to assess the quality of films that make up the structure of a solar element, as well as their use to
evaluate technological processes when manufacturing a solar element.
It is substantiated that the use of the described methods contributes to the development of
reliable, efficient and cheap solar elements; however, it is obvious that no diagnostic method is able
to reflect all the variety of information regarding the parameters of thin-film solar elements.