https://doi.org/10.15407/iopt.2022.57.043

Optoelectron. Semicond. Tech. 57, 43-70 (2022)

O. I. Vlasenko, Z. K. Vlasenko

INDUCED RESTRUCTURING OF THE CRYSTAL STRUCTURE AND ACOUSTIC RESPONSE IN SEMICONDUCTORS BASED ON CADMIUM TELLURIDE FOR USE IN OPTOELECTRONICS AND TOPICAL AREAS OF SEMICONDUCTOR TECHNOLOGY (REVIEW)

The reliability and competitiveness of modern semiconductor electronic technology are determined by the level of existing technologies. These requirements set the task of increasing the efficiency of methods for obtaining and post-growth processing of semiconductor materials and structures, research and control of their properties at all stages of manufacturing and operation of products.

The question of the quality and maximum reliability of a wide range of various structures and devices for multipurpose purposes, in particular, opto, photoelectronics, sensors, etc., and sometimes the need to use it at the most achievable physical and technical parameters, or in extreme conditions, is becoming increasingly important. The solution to these problems is based on a comprehensive study of the processes of defect formation, failure and destruction of semiconductor structures and devices based on them. In modern conditions, for this purpose, in particular, the method of acoustic emission (AE) is used, based on the registration, theoretical processing of acoustic pulses that arise as a result of the formation, local changes and destruction of the structure of the material under external load. The most widespread practical application in various branches of semiconductor electronics have found materials based on CdTe, given, in particular, basic data on methods and sources of acoustic response induced by external influences. 

This method makes it possible to obtain information about the state of a solid in the process of deformation, in particular, to detect in a non-destructive way the presence or appearance of dislocations and microcracks. The AE process allows you to determine the mechanical stresses and deformations at which there is a transition from elastic to plastic deformation (yield strength) of the crystal and subsequent destruction. AE, which occurs during the deformation of a solid in local areas, in particular, under mechanical loads, ultrasound, laser irradiation, radiation exposure and in other cases, may have a thermomechanical nature and occur as a result of heterogeneous heating, for example, during the flow of electric current through a heterogeneous medium. Mechanical, thermomechanical or thermobaric stresses appear in crystals under appropriate phase transformations, in particular, during melting during laser irradiation. 

Thus, AE is an effective non-destructive method for identifying the initial stages of degradation and subsequent destruction of semiconductor materials, structures and devices under various external influences. The main purpose of this review is to distribute AE from macro objects (in technical diagnostics and control of industrial and domestic structures) to micro-objects for materials and structures of low-dimensional electronics, to expand the scientifically conscious application of AE in experimental and practical work in various semiconductor materials and structures on the example of CdTe-based semiconductors (wide- and narrow-band).

Keywords: acoustic emission, mechanical loads, movement of dislocations, cracks, restructuring of the crystal structure, phase transitions, laser irradiation, ultrasonic load, radiation exposure, degradation, destruction of crystals.