Channeling depth distributions of Be and Si in GaAs as a function of implantation energy and fluence

Be and Si are commonly employed p- and n-type respectively dopants, implanted in GaAs. Channeled implantation produces deeper and sharper profiles than standard random implants. To employ channeling, we need to know how the profile shape, depth, and doping density vary with implantation energy and fluence, and what maximum density can be achieved. This work shows how channeling profiles in the direction of GaAs vary with energy and fluence for room temperature channeling. Data are shown for fluences of 3 × 10¹², 3 × 10¹³, and 3 × 10¹⁴cm^-2and energies of 40, 75, 150, and 300 keV. The deep channeling profile saturates for 150 keV Be just below a fluence of 3 × 10¹⁴cm^-2and a density of about 4 × 10¹⁷cm^-3can be achieved at depths of about 1 to 3 µm for energies from 75 to 300 keV. The maximum density for 150 keV Si for room temperature channeling is about 4 × 10¹⁶cm^-3and occurs at depths from 1 to 4 µm in the energy range from 40 to 300 keV.