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To get an insight in the diffusion behavior of dopants such as arsenic and boron after annealing and in particular their segregation characteristics towards the interface in oxide structures on silicon, it is necessary to probe the dopant profile with very high accuracy and depth resolution. Sputter depth profiling as employed in secondary ion mass spectrometry (SIMS) is frequently used as the most suited tool for dopant profiling in view of its sensitivity and depth resolution. However in order to determine the segregated arsenic/boron peak, sub-nanometer depth resolution is required and artifacts such as beam induced broadening effects, potential ionization yield changes at interfaces, transient sputter yields need to be considered in detail. When reducing the primary beam energy the depth resolution can be improved and sub-nanometer depth sensitivity can be demonstrated. However comparisons with high resolution elastic recoil detection analysis demonstrate that it is at present impossible to obtain a reliable depth profile in the first nanometer near the surface nor even in the oxide part of the profile, where no ionization nor sputter yield transients are expected. Enhanced beam induced migration of boron during the initial phase of the bombardment needs to be invoked to explain the results. The latter appears to be enhanced under conditions (∼normal incidence) where full oxidation occurs.

For the first time, a novel junctionless (JL) FinFET structure with a shell doping profile (SDP) formed by molecular monolayer doping (MLD) method and microwave annealing (MWA) at low temperature is proposed and studied. Thanks to the ultra thin SDP leading to an easily-depleted channel, the proposed JLFinFET can retain the ideal subthreshold swing (∼ 60 mV/dec) at a high doping level according to simulations. Poly Si based JLFinFETs processed with MLD and MWA exhibit superior subthreshold swing (S.S. ∼ 67mV/dec) and excellent on-off ratio (>106) for both n and p channel devices. Threshold voltage (V TH ) variation due to random dopant fluctuation (RDF) is reduced in MLD-JLFinFETs, which can be attributed to the molecule self-limiting property of MLD on the Si surface and quasi-diffusionless MWA at low temperature. Our results reveal the potential of the proposed SDP enabling a JLFET showing reduced variation and outstanding performance for low power applications.

Photoluminescence intensity (PL-I) data are presented for 22 dielectric/GaAs systems investigated for MOSFET applications. The PL-I technique has been identified as a most useful and reliable tool for screening dielectric/GaAs interfaces and has been instrumental in the identification of a device quality dielectric/GaAs interface: in situ deposited Ga2O3 on GaAs. The early discovery of such an interface has allowed us to focus resources and to succeed to manufacture GaAs MOSFETs which perform in line with theoretical model predictions after more than 40 years of failed attempts. It is strongly recommended to extend the technique to the investigation of CMOS relevant channel materials such as InGaAs.

Bulk-doped silicon wafers were measured at four EAG (Evans Analytical Group) site laboratories in a round-robin study of the calibration of SIMS measurements of dopant concentrations in silicon. Mean B, P, and As concentrations were determined for several bulk-doped silicon reference wafers. Absolute concentration calibration scales are determined by NIST Standard Reference Materials (B, As) or accepted Consensus Reference Materials (P). At any single EAG measurement site, the average repeatibility of an individual dopant concentration measurement was about 0.7% for B, 2.1% for P, and 2.3% for As. Across the four sites, the best reproducibility for concentration measurements was found when bulk-doped standards were used for calibration. Average reproducibility of dopant concentration measurements across the EAG was 0.9% for B, 2.5% for P, and 2.6% for As.

A key problem faced by npn SiGe technology is the outdiffusion of boron from the SiGe base caused by thermal annealing or transient enhanced diffusion. In this paper we investigate the effects of C incorporation in the base on boron diffusion caused by thermal annealing and As emitter implantation. The higher Early voltages of the C transistors compared with that of the no-C transistors indicates that C incorporation in the base dramatically reduces the diffusion of B under postgrowth implantation and annealing procedures.