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Selective epitaxial embedded SiGe(B) (e-SiGe) is widely used for Source/Drain in advanced CMOS technologies for introducing compressive strain to the PMOS channel which improves the hole mobility. In this paper, we investigated SiGeB epitaxy on different substrates including SiGe, Si:B, SiGeB and also dielectric films including ALD/ CVD SiN, thermal/CVD SiO2. For SiGeB epitaxy on crystallized film substrates, results show that Germanium would prevent Boron inter-diffusion between the substrate and the following deposited SiGeB. Growth Rate (GR) of the epitaxy e-SiGe film is also investigated. A combination of the SiGeB film concentration and GR study shows that Boron concentration and strain introduced by lattice mismatch between the substrate and the epitaxial film are two competitive factors to the GR. The film grows faster when Boron concentration is higher while larger strain would degrade the GR. Selectivity study shows that CVD SiN film have the best selectivity. We also investigated the film selectivity before and after thermal anneal. Results show that film selectivity become worse after thermal anneal.

Compressive stress introduced by source/drain (S/D) SiGe is widely used in 45nm node and beyond advanced technology which boost the P-channel hole mobility. Quantitive measurement of localized stress in channel is limited by the scaling shrinking. Transmitted electron microscopy- Nano Beam Diffraction (TEM-NBD) is an effective method for the local stress distribution measurement in channel and well area derived from S/D Si1-xGex. In this paper, we study the channel strain from the following aspect, including i) active area (AA) width, ii) S/D recess shape, iii) S/D recess trench depth, and iv) Germanium (Ge), Boron (B) concentration of S/D Si1-xGex and Ge, B distribution profile. It is revealed that strain has strong relation with these factors. Pitch with narrow AA width shows lower strain than that of wider AA width. S/D recess shape affects the proximity which is critical for the stress derived from S/D SiGe transmit to channel location. Moreover, S/D recess trench depth determines the volume of filled SiGe then affect the strain to channel. Both of the Ge, B concentration of S/D SiGe and the distribution profile directly affects the lattice mismatch which results in the strain. In general, all these factors affect the volume of the filled SiGe and Ge concentration which eventually determine the strain of S/D to channel area.

Diesel and gasoline engines are the most important sources of energy consuming, emission and global warming. To increase fuel efficiency and reduce emission, air pressure ratio of the engine needs to be further increased. The increase of air pressure is achieved by a compressor wheel in the turbocharger. The compressor wheel needs very complex blade geometry to achieve high pressure ratios. The very latest technique for impeller manufacture is called semi-solid moulding (SSM). This paper will present recent development of SSM including thixo-casting and rheo-casting processes in making aluminium compressor wheels. Experimental results show SSM material has superior microstructure and mechanical properties over cast and is comparable to material machined from solid. Component testing including performance and durability testing proves the SSM compressor wheels emerge as being significantly more durable than cast equivalents and approaching that of machined impellers.