A comprehensive study of beryllium diffusion in InGaAs using different forms of kick-out mechanism

¹ Laboratoire Électronique, Microtechnologie et Instrumentation (UPRES EA 2654 du CNRS), LEMI-IUT-Université de Rouen, rue Lavoisier, 76821 Mont-Saint-Aignan, France
² Laboratoire de Mathématiques (UPRES A 6085 du CNRS), INSA de Rouen, B.P. 08, 76131 Mont-Saint-Aignan, France

Corresponding authors: Jerome.Marcon@univ-rouen.fr Kaouther.Ketata@univ-rouen.fr

Received: 19 June 1998
Revised: 23 October 1998
Accepted: 28 June 1999
Published online: 15 October 1999

Abstract

Be diffusion during post-growth annealing has been investigated in InGaAs epitaxial layers. Kick-out mechanisms considering species charges, built-in electric field and Fermi-level effect have been studied. Several forms of kick-out mechanism have been implemented in our simulation programs. Experimental concentration profiles obtained by SIMS analysis have been compared systematically with the numerical results of simulations. We have deduced that the kick-out mechanism Be_i⁰ ↔ Be_s⁻ + I_III⁺ is the dominating diffusion mechanism in InGaAs under our experimental conditions (C₀ = 3 × 19 cm⁻³). With our experimental data, we have found that the effective diffusion coefficient values are D = (7.7−9) × 10⁻¹³ cm² s⁻¹ at T = 700 °C and D = (1.4−1.5) × 10⁻¹¹ cm² s⁻¹ at T = 800 °C which is several orders of magnitude higher than most published data. A possible explanation would be the effect of V/III flux ratio.