Bi-axially highly-strained Silicon-On-Insulator (sSOI) substrates with a tensile stress up to 2.5 GPa have been obtained by Smart CutTM technology. Thin strained silicon (sSi) layers epitaxially grown on relaxed Si0.6Ge0.4 virtual substrates (VS) were used as starting materials. The threading dislocation density in those sSi layers was in the low 105 cm-2. Some stacking faults were also present in those highly strained Si films. The evolution of this linear defect density was characterized as a function of the sSi thickness by Secco etch. 2.5 GPa sSOI wafers have been demonstrated in 200 mm diameter. Stress uniformity σ equal to 1.14% and 2 nm thickness range has been obtained for 8 nm thick sSi layers.

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International audienceIn traditional beamline implantation, the incident ion mass and energy are well known parameters and simulation programs are available to predict the implant profiles. In plasma based ion implantation, all ionized species present in the plasma are extracted and implanted by applying negative voltage pulses to the wafer. Therefore, prediction of implant profile is more complicated since it requires the knowledge of relative abundance of each ion species as well as their energy distribution prior to entering the wafer surface. This information is not readily available using conventional plasma characterization techniques because most of them measure plasma bulk properties. In order to collect the information needed for predicting plasma implant profiles, an ion mass and energy spectrometer is installed at the wafer level to allow in situ measurement of ion mass and energy distribution. In this paper, BF3 plasma in the pressure range from 30 to 250 mTorr is studied. The relative flux and energy distribution of B+, BF+, BF2 +, and BF3 + ions striking the wafer surface with energies up to 1 keV are measured. As expected, no energy contamination was observed during a plasma doping implantation and the maximum energy of the ions is defined by the cathode voltage. Based on the spectrometer data, a series of simulations was performed to calculate the boron and fluorine dopant depth profiles. The calculated profiles were in good agreement with secondary ion mass spectrometry (SIMS) results and give some additional explanations of the unique surface-peaked SIMS profile of plasma doping implantatio

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The recent progress in the fabrication of GeOI substrates and devices is reviewed. Improvements have been made in threading dislocation density, Ge-buried oxide interface passivation, device performance. The potential of various co-integration schemes (lateral and vertical) has been illustrated as alternatives to the fabrication of n-type germanium channel devices. GeOI is also shown to be a versatile platform for the monolithic integration of Si and III-V devices and tunneling field effect transistors.