Elastic constants and optical phonon frequencies of BX (X= P, As, and Sb) semiconductors: Semi-empirical prediction

Salah Daoud,Hamza Rekab-Djabri,Pawan Kumar Saini

doi:10.14419/ijpr.v8i2.31001

Abstract

Based on some simple empirical formulas established by Adachi in, Properties of group-IV, III-V and II-VI semiconductors, John Wiley & Sons, Chichester (2005), and the experimental lattice constants reported in the literature; the present work aims to predict the elastic constants and some other significant properties of cubic zinc-blende boron compounds (BP, BAs and BSb). The obtained values of C12and C44 are in general good agreement with other data of the literature, while C11 and B are slightly lower. The zone-center longitudinal optical (LO) and transverse optical (TO) phonon frequencies are also obtained. The LO and TO phonon frequencies of BP compound were found at 866.6and 834.5 cmâ€“1, respectively; these of BAs were found at 731.3 and 727.1 cmâ€“1, respectively; while for the BSb narrow-gap semiconducting compound were found at around 598.3and 586.2 cmâ€“1, respectively. These two later values are in general slightly lower than the calculated values, and the observed Raman spectroscopy values reported in the literature.Â

Highlights

Among group III–V semiconducting materials, binary boron compounds, which have attracted great attention in recent years
Based on some simple semi-empirical and empirical formulas, and some experimental and theoretical data reported in literature, we tried to predict the elastic constants and related properties of cubic zinc-blende BP, BAs and BSb materials
Except the values of C12 and C44, these of C11 and B are slightly lower than the experimental and other theoretical values reported in the literature

Summary

Introduction

Among group III–V semiconducting materials, binary boron compounds, which have attracted great attention in recent years. The bulk modulus B is expressed as a function of the elastic constants C11 andC12as follow [13, 16]: B = (C11+2C12)/3.Ourcalculated values of B for BP, BAs and BSb are around 160.51, 132.28, and 90.11 GPa, respectively. They are summarized, along the results obtained in Refs. For crystals with cubic diamond and cubic zinc-blende structures; the internal strain parameter and the elastic constants are related by following expression [18]: ζ = (C11+8C12)/(7C11+2C12).For BP, BAs and BSb compounds, our calculated values of ζ are around: 0.46, 0.49, and 0.57, respectively. We note that the use of the empirical method slightly underestimates the Knoop microhardness H of BSb compared to the available values, while the discrepancy becomes more important for BP and BAs

This work

Findings

Conclusion