The purpose of this review article is to report on the recent developments and the performance level achieved in the strained-Si/SiGe material system. In the first part, the technology of the growth of a high-quality strained-Si layer on a relaxed, linear or step-graded SiGe buffer layer is reviewed. Characterization results of strained-Si films obtained with secondary ion mass spectroscopy, Rutherford backscattering spectroscopy, atomic force microscopy, spectroscopic ellipsometry and Raman spectroscopy are presented. Techniques for the determination of bandgap parameters from electrical characterization of metal-oxide-semiconductor (MOS) structures on strained-Si film are discussed. In the second part, processing issues of strained-Si films in conventional Si technology with low thermal budget are critically reviewed. Thermal and low-temperature microwave plasma oxidation and nitridation of strained-Si layers are discussed. Some recent results on contact metallization of strained-Si using Ti and Pt are presented. In the last part, device applications of strained Si with special emphasis on heterostructure metal oxide semiconductor field effect transistors and modulation-doped field effect transistors are discussed. Design aspects and simulation results of n-and p-MOS devices with a strained-Si channel are presented. Possible future applications of strained-Si/SiGe in high-performance SiGe CMOS technology are indicated.

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Electronic applications of graphene synthesized from graphite electrode of waste dry cell battery.

A capacitance model is developed and a correction formula is derived to reconstruct the intrinsic oxide capacitance value from measured capacitance and conductance of lossy MOS devices. Due to discrepancies during processing, such as cleaning, an unwanted lossy dielectric layer is present in the oxide/semiconductor interface causing the measured capacitance in strong accumulation to be frequency dependent. The capacitance-voltage characteristics after correction are free from any frequency dispersion effect and give the actual oxide thickness in accumulation at all frequencies. Simulation of the measured capacitance-frequency curve was carried out using the model. The model was applied to SiO 2 /Si, SiO 2 /strained Si and GaO 2 /GaAs MOS capacitors.

Abstract-Performance enhancements of up to 170% in drain current, maximum transconductance, and field-effect mobility are presented for nMOSFETs fabricated with strained-Si channels compared with identically processed bulk Si MOSFETs. A novel layer structure comprising Si/Si 0 7 Ge 0 3 on an Si 0 85 Ge 0 15 virtual substrate (VS) offers improved performance advantages and a strain-compensated structure. A high thermal budget process produces devices having excellent on/off-state drain-current characteristics, transconductance, and subthreshold characteristics. The virtual substrate does not require chemical-mechanical polishing and the same performance enhancement is achieved with and without a titanium salicide process.