Beryllium diffusion mechanisms in InGaAs compounds grown by gas source molecular beam epitaxy

The redistribution of the p-type dopant Be during the post-growth rapid thermal annealing in InGaAs layers grown by gas source molecular beam epitaxy has been studied using secondary ion mass spectrometry technique. The experimental structures consisted of a 2000 Å Be-doped ($3\times 10^{19}\,{\rm cm^{-3}}$) $\rm In_{0.53}Ga_{0.47}As$ layer sandwiched between 5000 Åundoped $\rm In_{0.53}Ga_{0.47}As$ layers. To explain the observed depth profiles, obtained for annealing cycles with time durations of 10 to 240 s and temperatures in the range of 700-$\rm 900 {}^\circ C$, two models of kick-out mechanism, with neutral and singly positively ionized Be interstitial species, have been considered

The modeling of beryllium diffusion in InGaAsP layers grown by GSMBE under nonequilibrium conditions

This study reports on Be diffusion in InGaAsP layers grown by gas source molecular beam epitaxy. The experimental structures consisted of a 2000 Å Be-doped (3 × 109 cm−3) In0.73Ga0.27As0.58P0.42 layer sandwiched between two 5000 Å undoped In0.73Ga0.27As0.58P0.42 layers. The samples were subjected to rapid thermal annealing in the temperature range from 700 to 900 °C with time durations of 10 to 240 s. Secondary ion mass spectrometry was employed for a quantitative determination of the Be depth profiles. Concentration profiles of Be in InGaAsP have been simulated according to two kick-out models: the first model involving neutral Be interstitials and singly positively charged Ga, In self-interstitials, and the second model involving singly positively charged Be interstitials and doubly positively charged Ga, In self-interstitials. Comparison with experimental data shows that the first kick-out model gives a better description

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

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 Bei0 ↔ Bes− + IIII+ 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

Study of the electrical activation of Si+-implanted InGaAs by means of Raman scattering

Raman scattering has been used to study the lattice recovery and electrical activation of Si+-implanted In0.53Ga0.47 As achieved by rapid thermal annealing. The degree of crystallinity recovery, of totally amorphized samples is studied for annealing temperatures between 300 and 875degreesC. A good degree of recovery is achieved for an annealing temperature of 600degreesC. Higher annealing temperatures are required to electrically activate the Si donors. The observed LO phonon-plasmon coupled modes allow us to monitor the electrical activation by means of Raman scattering. We find that electrical activation sets in for annealing temperatures around 700degreesC, and gradually increases up to an annealing temperature of 875degreesC. The optimal conditions for the rapid thermal annealing are found to be 875degreesC for 10 s