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CoSi2 is a promising material for self-aligned silicide (salicide) applications in sub-0.25 μm complementary metal–oxide–semiconductor (CMOS) technology. In conventional salicide technology, silicides are formed by a solid-state reaction (SSR) after source/drain formation. With the continued scaling down of junction depths, surface and interface roughness of silicides is a growing concern. In this work, a comparative study has been made to investigate the morphology and thermal stability of CoSi2 formed by SSR of different structures, i.e. Co/Si, TiN/Co/Si, Ti/Co/Si, Co/Ti/Si and Ti/Co/Ti/Si. Atomic force microscopy and other techniques were used to characterize the morphology and thermal stability. Compared with the Co/Si reaction, TiN or Ti capping reduces the roughness and improves the thermal stability. The reaction with a Ti interfacial layer shows epitaxial growth of CoSi2 on Si (100). The morphology and thermal stability of epitaxial CoSi2 were significantly improved. The epitaxial CoSi2 may be useful for contact in deep submicrometer CMOS devices.

ZrO2 thin film with suitable dielectric constant for MFIS FET's application was prepared by novel metal-organic-decomposition (MOD) method. The dielectric constants of the thin film laid between 10 and 30 and increased with the development of the crystallinity. The magnitude of the leakage current of the thin film with thickness of 27nm and 35nm was 1E-5 and 1E-7 A/cm2 respectively when 5V bias voltage was applied. The C-V characteristics show a memory window of 2.5V for a sweep voltage from -5V to +5V. It indicates that the thin film could satisfy the requirement of MFIS structure.

X-ray photoelectron spectroscopy (XPS) and Auger-electron spectroscopy (AES) measurements have been used to study the practical Pt/InP interface. Evidence for the formation of platinum phosphide by chemical reaction at this interface is obtained. A monotonic decrease of the intensity ratio for two Pt4f spin-orbit-split peaks wth decraseing phtoemission angle is measured. Some possible interpretations for this change are also presented.

The electrical transport properties of CoSi2 and Co(SixGe1−x)2 thin films formed by solid state interaction and co‐evaporation in the range of 4–300 K were studied. The Hall effect data indicate a hole carrier conduction in all samples. The rapid thermal annealed CoSi2 exhibits a typical metallic conduction with a residual resistivity of 3.3‐μΩ‐cm and room‐temperature (RT) resistivity of 15 μΩ cm. The co‐evaporated CoSi2 and Co(Si0.9Ge0.1)2 films after low temperature annealing up to 250 °C show a low resistivity of 70–80 μΩ cm at RT and change little down to 4 K. The hole carrier density of all the samples studied has values close to 2–3×1022 cm−3, while the carrier Hall mobility has large differences.

The experimental results on solid phase epitaxy of ion beam sputtered SiGe film on Si(100) substrate are presented. The SiGe/Si hetero-epitaxy is achieved by high temperature thermal processes such as diffusion, annealing, and oxidation. X-ray diffraction, Raman spectroscopy, and Rutherford backscattering spectroscopy show the epitaxial character of SiGe film on Si substrate.

Co/Ti/Si ternary solid phase interaction is a new method of CoSi/sub 2//Si hetero-epitaxy. The experimental results on Co/Ti/Si solid state interaction behavior, epitaxial growth of CoSi/sub 2/ on Si substrate, self-aligned silicidation of source/drain contact and polysilicon gate by Co/Ti/Si solid phase reaction, and applications of the new salicide technology in device fabrication are described and discussed.

Solid state reaction of TiN/Co/Ti multilayer with PECVD amorphous silicon has been studied. Experimental results show that uniform polycrystalline CoSi/sub 2/ with good thermal stability and smooth surface can be obtained after thermal annealing.

The solid phase hetero-epitaxial growth of amorphous SiGe on Si(100) substrate has been investigated in this paper. The experimental results indicate that the solid phase epitaxy of the heterostructure Si/sub 1-x/Ge/sub x//Si can be achieved with different compositions through high temperature thermal processes such as boron diffusion, annealing and oxidation.

The Co/a-SiGe/Si solid state reaction has been studied in this paper. The experimental results demonstrated the simultaneously SiGe/Si solid phase hetero-epitaxy and CoSi/sub 2//SiGe contact formation. The SiGe crystallization is a result of the Ge rejection and interdiffusion with Si during the Co/a-SiGe/Si ternary interaction.

The thermal stability of thin CoSi2 films formed from four layered structures: Co/Si, TiN/Co/Si, Co/Ti/Si and TiN/Co/Ti/Si has been studied using four-point-probe (FPP), TEM and RBS/channeling. It is found that thermal instability can be influenced by the polycrystalline structure in CoSi2. Growing epitaxial CoSi2 film on Si (100) using TiN capping and Ti interfacial layers can improve the thermal stability of thin CoSi2 film.

CoSi 2 is being investigated intensively for microelectronics application recently. In this paper a new method of growing an epitaxial CoSi 2 film by solid state reaction of Co/Ti/Si and TiN/Co/Ti/Si multilayer is described. The variation of structure and sheet resistance of the film with thermal annealing temperature and time has bee investigated. The kinetics and mechanism of the CoSi 2 solid-state epitaxy are discussed.

A new method of epitaxial growth of CoSi2 film on Si substrate by ternary solid state interaction is investigated. XRD, RBS and TEM show that single-crystalline CoSi2 can be formed on both Si (111) and (100) substrates by using Co/Ti/Si or TiN/Co/Ti/Si multilayer. The evolution of multilayer structure and its resistivity is studied and epitaxy mechanism is discussed. Experimental results indicate strong affinity between Co and Si. During the ternary interaction the epitaxial CoSi2 can be grown directly on Si and its growth may behave as a diffusion controlled process. The thickness of Ti layer and the annealing procedure have important effect on CoSi2 epitaxial growth.

The electrical resistivity and Hall effect of TiSi2 thin films were measured systematically in the temperature range of 2–300 K. The results were compared with theory and other work. The TiSi2 films were formed by Ti/Si solid‐state interaction on crystalline silicon or polysilicon substrates. The temperature dependence of the electrical resistivity of TiSi2 was approximated by the Bloch–Gruneisen theory. The Hall‐effect data show a multicarrier conduction mechanism in TiSi2. At low temperatures the Hall coefficient is positive for both substrates, but is negative at room temperature. The temperature at which the change of sign occurs is approximately 180 K for the crystalline‐Si substrate, and approximately 90 K for the polysilicon substrate. This is discussed briefly in terms of scattering mechansims for a simple model of the electronic structure.

Rapid modification of thin films on a semiconductor silicon wafer was carried out using a large-area cold cathode discharge electron beam. Three processes were undertaken using this novel electron beam. Firstly, in the rapid processing of a boron-ion-implanted silicon wafer, sheet resistance, X-ray diffraction, Raman spectroscopy and secondary ion mass spectrometry analyses indicated that this technique has the advantage of rapid processing with little diffusion of the dopants. Secondly, in the formation of TiN on an SiO 2 /Si wafer by rapid nitridation modification with this electron beam, the results of Rutherford backscattering spectrometry and X-ray diffraction studies showed evidence for TiN in the specimen after several tens of seconds of exposure to the electron beam. Thirdly, in the dry anisotropic etching of molybdenum films, an etching rate of greater than 175 nm min −1 was obtained in a CF 4 HeO 2 gas mixture. Scanning electron microscopy revealed a linewidth of 1.5 μm and showed the effect of anisotropic etching. Rapid modification by the electron beam may be concluded to be a predominant driving mechanism.

Rapid nitridation of Ti film evaporated on a Si and SiO2/Si wafer using a large area electron beam has been described. A predominant enhanced processing of an e‐beam should be considered. The film structure of the sample processed by an e‐beam has been characterized by Rutherford backscattering (RBS) and secondary ion mass spectrometry (SIMS) analysis, after rapid processing. Identification of the chemical composition of the film was performed with x‐ray diffraction. The minimum sheet resistance of TiN was about 0.6 and 14.2 Ω/⧠ for Si and SiO2/Si substrate, respectively. A ratio of 0.96%±5% (N/Ti), the stoichiometric composition of the sample characterized by RBS, has been obtained.

For practical titanium silicide device application the oxygen behavior in the solid phase interaction is important to study. The Ti/Si and Ti/SiO2 interaction by the NH3 plasma assisted thermal annealing and oxidation of Ti/SiO2 and TiSi2/Si in a wet oxygen ambient were investigated by Auger electron analysis. The characteristic Auger spectral line shapes of Ti, O, and Si and their changes in compounds were measured. The experiment clearly demonstrated the oxygen snowplow effect during TiSi2 and TiN growth, and a stable SiO2 can be grown on TiSi2/Si directly or through a layer of TiO2.