Gas source molecular beam epitaxy grown strained-Si films on step-graded relaxed Si1-xGex for MOS applications

Gas source molecular beam epitaxy has been employed for the growth of a hig h quality strained-Si layer on a completely relaxed step-graded Si1-xGex bu ffer layer. As-grown strained-Si layers have been characterized using secon dary ion mass spectroscopy, Rutherford backscattering spectroscopy, atomic force microscopy, and spectroscopic ellipsometry for the determination of c omposition, thickness, crystalline quality, and surface roughness. Heteroju nction conduction and valence band offsets (Delta E-c, Delta E-v) of strain ed-Si/SiGe heterostructure have been determined from measured threshold vol tages of a strained-Si channel p-metal oxide semiconductor field effect tra nsistor (MOSFET) fabricated using grown films. MOS capacitance-voltage prof iling has been employed for the extraction of strained-Si layer thickness a nd apparent doping profile in the device.