Методы исследования электрофизических характеристик эпитаксиальных слоев твердых растворов типа n/p-InxGa1–xAs для приборных структур большой площади

Abstract

The production of epitaxial layers requires the search for simple, technologically advanced and accurate methods for assessing the basic properties of layers and compositions made from them. The issue is especially acute for developers of multistage photovoltaic converters (PVCs) for space applications, which are distinguished by a complex heterostructure, including 5 or more p-n junctions and a large area. The work carried out a search for an optimal method for studying the electrical characteristics of thin semiconductor layers of the n/p-InxGa1-xAs type with different doping levels. The main task is to measure the basic electrical characteristics in various ways: resistivity (conductivity), concentration of the main charge carriers, the dependence of the main electrical parameters on the type and level of doping and their comparison. Using the example of p- and n-type In0.01Ga0.99As solid solutions obtained by MOS-hydride epitaxy, a technique for studying the main electrical characteristics of epitaxial layers is proposed, taking into account the assessment of homogeneity on large-area samples. A comparison of the results obtained by various methods is presented: photoluminescence, non-contact measurement of surface resistance, Van der Pauw (Hall effect) and capacitance-voltage (electrochemical profiling (ECP), in situ control methods. Based on the results obtained and comparison with literature data, conclusions are drawn about the need, sufficiency and complementarity of methods for monitoring and studying semiconductor epitaxial structures.