Publisher Summary This chapter discusses the development and progress of stimulated scattering studies over the past four to five decades. The chapter focuses on the principles (mechanisms or models), basic experimental features, and technical applications of various stimulated scattering effects and related processes. Stimulated scattering is a very broad research subject. The key issues of the impulsive stimulated (Brillouin, Raman, and thermal) scattering studies are focused on the dynamic responses of short (or ultrashort) laser pulse-induced phonon fields. In a similar manner, studies of stimulated scattering in plasmas are mainly aimed at exploring opto-physical properties of the plasma medium. Other stimulated scattering-related issues, such as the CARS effect is a Raman-enhanced four wave frequency-mixing (FWFM) process, which requires phase-matching condition and can only occur in the forward direction.

Chapter 4 Stimulated Scattering Effects of Intense Coherent Light

Fully depleted silicon on insulator (FDSOI) devices with high-k dielectrics and metal gate are promising candidates for sub-45‐nm complementary metal oxide semiconductor technologies. At present, the gate length reduction becomes more and more difficult due to resist thickness diminution induced by critical dimension downscaling. In order to suppress resist thickness limitations, we have added a carbon layer with a SiO2 capping onto the conventional dielectric hard mask (SiO2 or Si3N4). In this study, FDSOI transistors with hafnium dielectric (HfO2), titanium nitride (TiN) metal gate were patterned by combining high resolution hybrid lithography (electron beam∕deep ultraviolet) and amorphous carbon hard mask. Full three-dimensional (3D) characterizations were carried out by using 3D atomic force microscope (CD-AFM from Veeco) to determine the best process window. Finally, after carbon hard mask trimming, sub-30‐nm gate length transistors were achieved and successfully electrically tested.

Sub-30-nm hybrid lithography (electron beam/deep ultraviolet) and etch process for fully depleted metal oxide semiconductor transistors

Publisher Summary The chapter provides some basic results about the elastic description of a bulk solid and its surface, and emphasizes on surface stress and surface strain quantities and on the description of surface defects in terms of point forces. It focuses on the morphological stability of a stressed surface and epitaxially strained crystal as well. It shows how surface stress modifies wetting conditions and how bulk stress modifies the equilibrium state. For two-dimensional (2D) growth (perfect wetting), bulk strain modifies the chemical potential of each layer and due to finite size wetting, it results in a number of equilibrium layers for each imposed undersaturation. For three-dimensional (3D) growth (no perfect wetting), the epitaxial stress acts against wetting and leads to a global thickening of the equilibrium shape. The chapter also shows how elastic relaxation is a prerequisite for the simultaneous existence of 2D layers and 3D crystals. In the three cases of 2D, 3D, or Stranski-Krastanov (SK) mixed mode, beyond some critical size, plastic relaxation may occur. The chapter also provides information on elastic effects on growth mechanisms.

/pdf/some-elastic-effects-in-crystal-growth-3cuziqvna8.pdf

Some elastic effects in crystal growth

Finite Element Analysis of Thermodynamically Consistent Strain Gradient Plasticity Theory and Applications

A rapid shrinkage in the minimum feature size of integrated circuits requires analysis of dopants in their shallow source–drain and their extensions with an enhanced depth resolution. Rutherford backscattering spectroscopy (RBS) combining a medium-energy He ion beam with a detector of improved energy resolution should meet the requirement of a depth resolution better than 5 nm at a depth of 10–20 nm in the next 10 years. A toroidal electrostatic analyzer of 4×10−3 energy resolution has been used to detect the scattered ions of a medium-energy He ion beam. Five keV As+ implanted Si or SiO2 samples were measured. Depth profiling results using the above technique are compared with those of glancing-angle RBS by MeV energy He ions. Limitations in the energy resolution due to various energy-spread contributions have been clarified.

Development of enhanced depth-resolution technique for shallow dopant profiles

Stimulated Brillouin scattering (SBS) of unmodified XeCl laser radiation in n‐hexane was investigated for building phase‐conjugating mirrors. It was found that the SBS mirror reflectivity could be improved by setting a holographic grating in front of the SBS mirror and by using the first order beam reflected by the grating to pump the Brillouin medium. Maximum energy and power reflectivities of 45% and 80%, respectively, were measured. The SBS mirror energy reflectivity was reduced by 45% by removing the grating. The phase conjugation fidelity of the backscattered radiation was close to one, with or without the grating.

Y. B. Yao

Papers

On the improvement of broadband stimulated Brillouin scattering reflectors