166 ISSN 1063-7397, Russian Microelectronics, 2020, Vol. 49, No. 3, pp. 166–172. © Pleiades Publishing, Ltd., 2020. Russian Text © The Author(s), 2020, published in Mikroelektronika, 2020, Vol. 49, No. 3, pp. 179–185. Role of Readsorption in the Formation of Vertical A III B V Nanowires with Self-Catalytic Growth A. G. Nastovjak a, *, A. G. Usenkova b , N. L. Shwartz a, b , and I. G. Neizvestny a, b a Rzhanov Institute of Semiconductor Physics, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090 Russia b Novosibirsk State Technical University, Novosibirsk, 630073 Russia *e-mail: alla@isp.nsc.ru Received August 28, 2019; revised September 23, 2019; accepted November 22, 2019 Abstract—Using Monte Carlo simulations, we studied the effect of readsorption on the growth rate and mor- phology of A III B V nanowires. It is demonstrated that readsorption of arsenic leads to an increase in the growth rate and premature consumption of a seed drop. The reabsorption of metal atoms leads to a slowdown in the axial growth but prolongs the growth, since it prevents the droplet from disappearing after the length of the nanowire reaches the diffusion length of the metal atoms along the side walls of the wire. It is demonstrated that it is possible to increase the diffusion length of group III elements along the side walls of the nanowire using the pulsed growth mode. Keywords: nanowires, semiconductors, A III B V , MBE, modeling, Monte Carlo DOI: 10.1134/S106373972003004X INTRODUCTION Semiconductor nanowires (NWs) from A III B V materials can be used as the basic elements of various optoelectronic devices: lasers, LEDs, and solar cells [1–3]. The electrical and optical properties of nanowires are largely determined by their geometrical parameters; therefore, the controlled growth of nanowires with the given morphology is an urgent nanoengineering prob- lem. The key technology for creating NWs is the growth from metal droplets of the catalyst by the vapor–liquid–solid (VLS) mechanism. In recent years, A III B V NWs have been obtained by the method of self-catalytic growth when a metal of group III is used as a catalyst [4–11]. An important advantage of self-catalytic growth is the absence of impurities in the growing nanowire [12], while the narrow range of growth conditions in which growth is possible [11] and the premature disappearance of the seed drop are its disadvantages. The main condition for the stability of self-catalytic growth is the constancy of the size of the droplet at the top of the NW and the contact angle between the drop and the NWs [13]. A change in the diameter of the droplet during growth inevitably entails a nonuniformity in the diameter of the growing crystal along the growth axis. A number of devices require the creation of an array of high-density vertical nanowires. In [5, 14, 15], it was noted that the readsorption effect plays an important role in such NW arrays. The effect of the read- sorption of arsenic on the characteristics of the self-cata- lytic growth of GaAs nanowires was considered in [6], and Ga readsorption was considered in [5]. The growth of A III B V NW was studied using a num- ber of analytical models [16–18], which made it possi- ble to understand some aspects of self-catalytic growth. However, the growth mechanism of NWs includes many complex processes, not all of which can be described by analytical models [17]. The dynamics of self-catalytic growth is difficult to describe in a sin- gle analytical model, since, in addition to surface dif- fusion, the growth process includes the reevaporation of the material from the substrate and the side walls of the nanowires. The role of reevaporation increases for closely spaced nanowires with a large diameter and height. One of the most suitable methods for elucidating the kinetics and details of the growth of nanowires is Monte Carlo (MC) simulation [19–22]. In this paper, using Monte Carlo simulations, we studied the fea- tures of the self-catalytic growth of III–V nanowires according the VLS mechanism. The effect of compo- nent readsorption on the growth process was studied, and the possibility of preventing the premature disap- pearance of a metal droplet using the MBE pulsed mode was considered. Abbreviations: NWs, nanowires; VLS, vapor–liquid–solid; MC, Monte Carlo.