Characterization of Asþ ion-implanted layers in strained-Si/SiGe/Si hetero-structures

Arsenic ions were implanted in a strained-Si/SiGe/Si hetero-structure to fabricate an nþ layer in the substrate. The disordering of the substrate caused by ion implantation and the reordering during post-implant rapid thermal annealing (RTA) were analyzed by Rutherford backscattering and channeling (RBS) measurements. It was shown that the major part of implantation-induced defects was eliminated during RTA for 10 s above 900 8C. Electrical and atomic-concentration profiles for As-implanted layers were examined by differential Hall-effect and secondary ion mass spectrometric (SIMS) measurements, respectively. A 25-nm thick, nþ layer with carrier concentrations in a range of 5:2 1019 to 1:7 1020 cm 3 was formed in the strained Si layer after RTA at 10008 C without the deterioration in the abruptness of the Si/SiGe interface. It was also revealed that the electrons in the strained Si layer had a higher mobility than the electrons in bulk Si by a factor of around 1.2 in a carrier concentration range of mid-1019 to -1020 cm 3. # 2003 Elsevier B.V. All rights reserved