Abstract :
The desire for higher carrier mobilities for thin-channel CMOS, such as fully-depleted SOI, has focused attention on the behavior of dopants in Si1-xGex materials. In this work, the diffusion of boron implanted at 0.5 keV was studied for 5 sec anneals between 800 to 1050°C for silicon (Cz and epitaxial) and Si1-xGex layers with Ge content of 7 and 25%. The implant dose of boron ions was 5 × 1014 ions/cm2. The epi-silicon and Si1-xGex layers were ∼200 nm thick so that the entire diffused profile was within the epitaxial layers. Strongly increased diffusion, compared to Cz- and epi-silicon, was found for boron atoms in layers with the Ge content of 7% and 25% for anneal temperatures above 900°C.
Keywords :
Ge-Si alloys; boron; diffusion; doping profiles; ion implantation; rapid thermal annealing; secondary ion mass spectra; semiconductor thin films; 0.5 keV; 800 to 1050 C; CZ-silicon; SIMS; SiGe:B; boron diffusion; concentration profiles; diffused profile; epi-silicon; epitaxial layers; ion implant dose; junction depth; rapid thermal annealing; strain-state; Atomic layer deposition; Atomic measurements; Boron alloys; Epitaxial layers; Fabrication; Germanium alloys; Implants; Rapid thermal annealing; Silicon alloys; Temperature;
