Hydrogen plasma modification of shallow implanted Germanium layers

RF hydrogen plasma treatment, rapid thermal annealing and thermal annealing of high-dose implanted amorphized p-type Ge layers have been studied by Raman scattering spectroscopy, AFM, SIMS and electrochemical capacitance-voltage profiling. It is shown that low-temperature RF plasma treatment at temperature about 200 °C results in full recrystallization of thin amorphous Ge layer implanted by P⁺ ions and activation of implanted impurity up to 8 × 10¹⁹ cm ^-3 with maximum concentration about 20 nm in depth from surface. Rapid thermal annealing (15 sec) and thermal annealing (10 min) in nitrogen ambient demanded considerably higher temperatures for recrystallization and activation processes that resulted to diffusion of implanted impurity inside of the Ge bulk. Mechanisms of enhanced modification of the subsurface implanted Ge layer under plasma treatment are analyzed.