Abstract. In cryptography it is assumed that adversaries only have black box access to the secret keys of honest parties. In real life, however, the black box approach is not sufficient because attackers have access to many physical means that enable them to derive information on the secret keys. In order to limit the attacker's ability to read out secret information, the concept of Algorithmic Tamper Proof (ATP) security is needed as put forth by Gennaro, Lysyanskaya, Malkin, Micali and Rabin. An essential component to achieve ATP security is read-proof hardware. In this paper, we develop an implementation of read-proof hardware that is resistant against invasive attacks. The construction is based on a hardware and a cryptographic part. The hardware consists of a protective coating that contains a lot of randomness. By performing measurements on the coating a fingerprint is derived. The cryptographic part consists of a Fuzzy Extractor that turns this fingerprint into a secure key. Hence no key is present in the non-volatile memory of the device. It is only constructed at the time when needed, and deleted afterwards. A practical implementation of the hardware and the cryptographic part is given. Finally, experimental evidence is given that an invasive attack on an IC equipped with this coating, reveals only a small amount of information on the key.

Studies of the properties and characteristics of transition metal silicides have been stimulated by their (potential) use in integrated circuit technology. This review describes some of the most recent studies in this field of research. Formation mechanisms of silicides are discussed in some detail. A division is made between near-noble and refractory metal silicidation which aids in the understanding of differences in formation mechanisms of the various silicides. The evolution of the components of thin film stress during metal silicidation is also elucidated. In the review of the practical uses of these materials, emphasis is placed on specific processes involving laterally confined (self-aligned) silicide film formation as more advanced applications require film formation only in certain localized regions on a Si wafer. Specific attention is paid to the silicidation processes of TiSiz and CoSiz. The electronic structure of silicides is discussed on the basis of band-structure calculations and photoemission experiments. The important electrical characteristics of films are then examined in terms of the microstructure of the films. A review of the crystallographic (epitaxial) orientation relationships between silicide films and monocrystalline Si is given. The epitaxial growth of CoSiz and FeSiz on and in Si is discussed thoroughly. The review of epitaxial silicide formation is used as the basis for a description of some futuristic applications of these materials. One such application utilizes the semiconducting properties of a FeSiz phase while another employs the Schottky-barrier characteristics of silicide/Si interfaces for the formation of advanced transistors. The latest electrical results obtained from the semiconducting material and from a so-called permeable base transistor are presented.

We present a new lateral Schottky-based rectifier called the charge-plasma diode realized on ultrathin silicon-oninsulator. The device utilizes the workfunction difference between two metal contacts, palladium and erbium, and the silicon body. We demonstrate that the proposed device provides a low and constant reverse leakage-current density of about 1 fA/µm with ON/OFF current ratios of around 10 7 at 1-V forward bias and room temperature. In the forward mode, a current swing of 88 mV/dec is obtained, which is reduced to 68 mV/dec by back-gate biasing.Index Terms-Buried oxide (BOX), charge-plasma (CP) diode, diode, p-i-n diode, Schottky barrier, silicon-on-insulator (SOI).

Hot‐wire assisted atomic layer deposition (HWALD) is a novel energy‐enhancement technique. HWALD enables formation of reactive species (radicals) at low substrate temperatures, without the generation of energetic ions and UV photons as by plasma. This approach employs a hot wire (tungsten filament) that is heated up to a temperature in the range of 1300–2000 °C to dissociate precursor molecules. HWALD has the potential to overcome certain limitations of plasma‐assisted processes. This work investigates the ability of a heated tungsten filament to catalytically crack molecular hydrogen or ammonia into atomic hydrogen and nitrogen‐containing radicals. The generation of these radicals and their successful delivery to the wafer (substrate) surface are experimentally confirmed by dedicated tellurium‐etching and silicon‐nitridation experiments. It further reports on deposition of low‐resistivity oxygen‐free tungsten films by using HWALD, as well as on the effect of hot‐wire‐generated nitrogen radicals and atomic hydrogen in deposition of aluminum nitride and boron nitride films. In parallel, this work provides important illustrative examples of using in situ real‐time monitoring of deposition and etching processes, together with extracting a variety of film properties, by spectroscopic ellipsometry technique.

Abstract-We present the data on specific silicide-to-silicon contact resistance (ρ c ) obtained using optimized transmission-line model structures, processed for a broad range of various n-and p-type Si doping levels, with NiSi and PtSi as the silicides. These structures, despite being attractive candidates for embedding in the CMOS processes, have not been used for NiSi, which is the material of choice in modern technologies. In addition, no database for NiSi-silicon contact resistance exists, particularly for a broad range of doping levels. This letter provides such a database, using PtSi extensively studied earlier as a reference.

We present physical and electrical evidence of the Thomson The line-type PCM cells were fabricated as follows (Fig. 1). thermo-electric effect in line-type phase-change memory Two tungsten electrode pads were defined by a single cells. This causes a shift of the molten zone during RESET damascene process. A doped SbTe layer was then deposited programming towards the anode contact, and as a by sputtering, and structured by commonly used 193 nm consequence the phase change material (PCM) design at the photolithography and reactive ion etching (RIE). Three contact area has a significant influence on the program different line cell structures were defined: a fine line cell conditions. First statistical studies showed a reduction of (Fig. la), a line cell with flap-like PCM extensions at the minimum Reset currents by 5% and Set voltages by 28% contact area with the W electrode pads, i.e. so-called "Dogwhen PCM extensions around the anode are used instead of Bone" cell (Fig. lb), and an asymmetric T-shaped cell with fine line contacts. This Thomson effect remains important flap extension at one contact side only (Fig. 1 c). Line widths with further cell scaling.ranged between llOnm-300nm, and line lengths between 380-740nm. After patterning, the PCM cells were passivated

Spectroscopic ellipsometry (SE) was employed to investigate the growth of atomic layer deposited (ALD) TiN thin films from titanium chloride (TinormalCl4) and ammonia (NnormalH3) and the followed oxidation in dry oxygen. Two regimes were found in the growth including a transient stage prior to a linear regime. The complementary ex situ characterization techniques showed a good agreement with the results obtained from SE measurements. A columnar structure of the as-deposited TiN film, which was composed of grains surrounded by amorphous material in between, was obtained. The X-ray photoelectron spectroscopy (XPS) analyses indicated low chlorine impurity content and slightly N-rich TiN films. The existence of an intermixed layer between the nitride and oxide during the oxidation was verified by the XPS depth profile analysis for a partially oxidized TiN film. A three-layer optical model was constructed for SE in situ monitoring the oxidation. A four-regime oxidation was found for 15-nm TiN films whereas only two regimes were seen in the case of 5-nm films. A new oxidation mechanism was proposed to explain the oxidation behavior of thin TiN films.

In this work, we investigated an approach of hot‐wire assisted ALD (HWALD), utilizing a hot (up to 2000 °C) tungsten (W) wire. Tungsten films were deposited by this method using alternating pulses of WF6 gas and atomic hydrogen (at‐H). The latter was generated by catalytic dissociation of molecular hydrogen (H2) upon the hot‐wire. The W films were grown on a 100‐nm thick thermal SiO2. The growth process was monitored in real time by an in‐situ spectroscopic ellipsometer (SE). The real‐time SE monitoring revealed the coexistence of three processes: CVD, etching, and ALD of the W film. WF6 could back‐stream diffuse to the hot‐wire, resulting in WF6 decomposition and generation of a flux of fluorine (F). The latter caused etching of the grown W film and the filament, and provided extra tungsten supply, which might cause CVD. Higher pressure and higher carrier gas flow rate were found to largely suppress the back‐stream diffusion of WF6, which efficiently limited CVD. By controlling the dose of WF6 and process pressure, the etching had also been minimized. X‐ray photoelectron spectroscopy of optimized HWALD grown W revealed 99 at% of W; concentrations of oxygen and fluorine were lower than 1%, below the detection limit.