Study of concentration-dependent Be diffusion in GaInP layers grown by gassource molecular beam epitaxy

Concentration-dependent Be diffusion in GaInP layers grown by gas source mo lecular beam epitaxy has been studied using secondary ion mass spectrometry . At a growth temperature of 500 degrees C, apparent Be diffusion occurs at a doping level over 4 x 10(19) cm(-3). At lower temperature, the Be profil e exhibits a significantly reduced diffusion. In contrast to Zn diffusion i n metalorganic vapor phase epitaxy, no enhancement of Be redistribution in GaInP by adjacent n-type layers occurs. These results are explained based o n the interstitial-substitutional diffusion model. A p(+)-n(+) GaInP tunnel diode with a high reverse-biased conductance of 15 mA/cm2 at 1.7 mV has be en achieved. (C) 2000 American Institute of Physics. [S0021-8979(00)05110-0 ].