The addition of strain in uniaxially strained transistors by both SiN contact etch stop layers and recessed SiGe sources and drains

Abstract

Articles you may be interested inImpact of SiGe source/drain induced-compressive strain on low frequency noise in high-k/metal gate p-channel metal-oxide-semiconductor transistors SiN contact etch stop layers (CESL) and recessed SiGe sources/drains are two uniaxial strain techniques used to boost the charge carriers mobility in p-type metal oxide semiconductor field effect transistors (pMOSFETs). It has already been shown that the electrical performances of the devices can be increased by combining both of these techniques on the same transistor. However, there are few experimental investigations of their additivity from the strain point of view. Here, spatially resolved strain mapping was performed using dark-field electron holography (DFEH) on pMOSFETs transistors strained by SiN CESL and embedded SiGe sources/drains. The influence of both processes on the strain distribution has been investigated independently before the combination was tested. This study was first performed with non-silicided devices. The results indicated that in the channel region, the strain induced by the combination of both processes is equal to the sum of the individual components. Then, the same investigation was performed after Ni-silicidation of the devices. It was found that in spite of a slight reduction of the strain due to the silicidation, the strain additivity is approximately preserved. Finally, it was also shown that DFEH can be a useful technique to characterize the strain field around dislocations. V C 2012 American Institute of Physics. [http://dx.

Full characterization of ultrathin 5-nm low- k dielectric bilayers: Influence of dopants and surfaces on the mechanical properties

“…This depth is comparable to the layer thickness of the thinner bilayer sample, and so we attribute the intensity reduction in both samples to the top layer straining the bottom layer. We similarly observe a clear strain layer in the Si substrate due to the lower SiC:H layer, as expected for such films on Si [41]. For the EDS measurements, there is no direct sensitivity to hydrogen, but they provide a self-consistent evaluation of the relative amounts of Si, C, O, and N through the depth of each bilayer sample.…”

“…(a) STEM image obtained using a HAADF detector. Strain from the deposited films blurs the atomic contrast peaks in the Si substrate, as expected [41]. HAADF intensity also drops at the interface of the two films in the bilayer.…”

Combining 2 nm Spatial Resolution and 0.02% Precision for Deformation Mapping of Semiconductor Specimens in a Transmission Electron Microscope by Precession Electron Diffraction

“…These recesses were then filled with undoped SiGe using reduced pressure chemical vapor deposition (RPCVD). Uniaxial deformation in the silicon channel arising from both the recessed SiGe sources and drains and an effect from the Si 3 N 4 film is expected …”

Mechanics of silicon nitride thin-film stressors on a transistor-like geometry

“…[2][3][4] Different manners of implementation have been proposed. Source and drain regions can be built of epitaxial alloys such as silicon-carbon (Si x C 1-x ) [5][6][7][8] and silicon-germanium (Si x Ge 1-x ), [9][10][11][12] that have lattice parameters different from those of the Si matrix. The channel region is therefore confined between two strained pockets, and deforms to an equilibrium configuration.…”