The study of Ga+ FIB implanting crystal silicon and subsequent annealing

The FIB Ga+ irradiation damage on Si substrate under different ion dose ranging from 1013 ions·cm−2 to 1017 ions·cm−2 and its effective recovery were studied. Based on the characterization results of XPS depth profiles, Raman, electron microscopy and AFM, FIB Ga+ implantation and the damage’s evolution and recovery after annealing treatment have been comprehensively demonstrated. The concentration distribution of implanted Ga was changed with ion doses and the peak of Ga concentration moved to the surface as the ion doses increased. When the ion dose of implantation area is as high as 1.5 × 1017 ions·cm−2, an Ga-rich implanted layer with up to 40 at.% Ga is formed at the top of the amorphous Si layer, where implanted Ga atoms migrated to enable clustering. The mechanism of the FIBI layer serving as the etching mask was discussed based on the characterization results and analysis. After annealing at 800 °C for 30 min, Raman peak at 520 cm−1 is completely regained for Si samples implanted with different ion doses, even for large ion dose of 2.7 × 1017 ions·cm−2, where the FIB produced defects of point defects and amorphous silicon could gain sufficient energy to recrystallize.