Ge-Rich (70%) SiGe Nanowire MOSFET Fabricated Using Pattern-Dependent Ge-Condensation Technique

A top-down approach of forming SiGe-nanowire (SGNW) MOSFET, with Ge concentration modulated along the source/drain (Si_0.7Ge_0.3) to channel (Si_0.3Ge_0.7) regions, is presented. Fabricated by utilizing a pattern-size-dependent Ge-condensation technique, the SGNW heterostructure PMOS device exhibits 4.5times enhancement in the drive current and transconductance (G_m) as compared to the homojunction planar device (Si_0.7Ge_0.3). This large enhancement can be attributed to several factors including Omega-gated nanowire structure, enhanced hole injection efficiency (due to valence band offset), and improved hole mobility (due to compressive strain and Ge enrichment in the nanowire channel).     

The effect of turbulent mixing on the moving liquid layer energy conversion into the internal energy of a compressed gas and the character of the gas compression

The compression of a planar heated gas layer by a moving liquid layer and the effect of turbulent mixing at the liquid-gas interface on the character of gas compression were experimentally studied. The gas compression by the liquid layer in the deceleration stage is accompanied by development of the Rayleigh-Taylor instability and the turbulent mixing (TM). The liquid fragmentation in the TM zone leads to a sharp increase in the heat transfer from hot gas to liquid. As a result, the gas compression dynamics significantly differs, both quantitatively and qualitatively, from that observed in the case of a solid piston. The dynamics of a liquid layer featuring the TM was compared to that of an analogous layer in the case when the TM development was fully suppressed by increased layer strength. The level of the gas compression by the liquid layer exceeded (by a factor of up to ∼1.5) the compression achieved with a solid piston.     

Development of the Rayleigh-Taylor instability at the boundary of a friable medium layer accelerated by a compressed air flow

The results of experiments with a friable medium layer driven by a compressed gas flow are reported. A layer of polypropylene particles was accelerated in a square channel under the action of air pressure. The initial perturbation on the unstable layer boundary had a nearly sinusoidal shape. Since the medium possesses no tensile strength (and exhibits no surface tension), the unbound particles occurring in the protruding front regions (spikes) of the unstable layer boundary fall into the gas. In the depressed front regions (bubbles), the medium probably exhibits a certain densification and the resulting compressive strength hinders the bubble growth in the initial stage of instability development. The gas penetrating into the layer leads to expansion and fluidization of the layer.     

A small OCA on a 1/spl times/0.5-mm/sup 2/ 2.45-GHz RFID Tag-design and integration based on a CMOS-compatible manufacturing technology

This letter reports, for the first time, on the design strategy and process integration for a small on-chip-antenna (OCA) with a radio-frequency identification (RFID) tag chip-area /spl sim/1/spl times/0.5 mm/sup 2/. It is designed based on a 2.45-GHz RFID tag circuit with an inductive-coupling model. A patterned Al shielding layer is used to improve the consistency of the actual performance obtained from fabricated devices and those predicated from the design. The antenna's inductor coils were fabricated based on a conventional Cu-Damascene process. To achieve the required antenna performance (e.g., Q-factor), a set of thick USG and deep-via etch processes were specifically developed. Our results demonstrate that the dc power converted by the OCA is sufficient to enable the RFID tag chip to communicate with a corresponding 2.45-GHz RFID reader with a 1-mm distance.     

Effects of plasma treatments on structural and electrical properties of methyl-doped silicon oxide low dielectric constant film

In this article, a methyl-doped silicon oxide low k film for use in inter-level dielectric application has been characterized. The structural and electrical properties of films prepared by chemical vapor deposition before and after different etching and photo-resist stripping (PRS) plasma treatments were studied. Structural properties of the low k film with various extents of forming gas and O₂ plasma treatments were reflected by the contents of Si-CH₃ and Si-H bonds. Surface roughness of films with plasma treatments was closely linked to the ratios of the cage- and network-structures of Si-O. Electrical properties of plasma-treated films were dependent on the applications of both etching and PRS plasma chemistries. Forming gas PRS caused the least low k film structural change and electrical deterioration compared with O₂ treatment. Moreover, E_bd of films decreased significantly by CH₂F₂ versus C₄F₈ etch. The best electrical properties of the film was obtained with a leakage current density of < 1 × 10^− 8 A/cm² and a dielectric breakdown strength of ∼3.2 MV/cm after being subjected with C₄F₈ / N₂ / Ar trench etch and forming gas PRS treatment.     

Process improvement of 0.13 μm Cu/Low K (Black Diamond) dual damascene interconnection

Once fab develops a reliable integration scheme, the next step of process improvement and yield enhancement is very important for semiconductor industry, especially for the 0.13 μm Cu/Low K (Black Diamond^TM) dual damascene interconnection. In this paper, we discuss the process integration issues of the 0.13 μm Cu/Low K (Black Diamond^TM) dual damascene integration. Solutions to the issues were explored and reported. Resist poisoning issue was solved by modifying photoresist and planarizing bottom-anti-reflective-coating (BARC) scheme. As a result there is an increase of 20% electrical yield. The impact of via etch time on interface of via bottom was studied and etch time was optimized for the best electrical performance of via chains. One of major targets of the 0.13 μm Cu/Low K (Black Diamond^TM) dual damascene integration is the reliability improvement. It was observed that Cu cap etch results in different via chain profiles. Good profile of via chain is achieved after optimizing of Cu cap etch and via etch. The failure open rate of via chain and the highest dielectric breakdown field were also reported. The impacts of dual damascene cleaning on the reliability of the 0.13 μm Cu/Low K (Black Diamond^TM) dual damascene interconnection was studied with splits between batch process and single wafer cleaning. On the whole, we successfully integrated 0.13 μm Cu/Low K (Black Diamond^TM) dual damascene interconnection with good electrical and reliability performance after process improvement of patterning, via/Cu cap etch and dual damascene cleaning.     

Interaction of dispersed water with flame

The electric explosion of a wire in a thin-walled cylindrical glass ampule filled with water results in the formation of a disperse water (DW) cloud having a ring shape, which expands rapidly in the radial direction and slowly in the axial direction. Interaction of the DW with a flame produces fire quenching in the interaction zone. Experimental results are used for estimating the requirements and consumptions for creating DW clouds capable of quenching large-scale fires.     

Development of new preservatives

Preservative-stamping oil Volgol-131 has been developed on the basis of a mixture of high-purity mineral oil and a group of additives that impart the desired service properties to the given product. The oil can be used in stamping operations and to provide long-term corrosion protection to cold-rolled products that have undergone electrolytic or hot galvanizing. The oil can be applied to the surface of the metal by dipping, rubbing, or spraying (including electrostatic spraying). One of the newest products of the company Volgokhimneft’ is water-soluble preservative Volgol-500, which was developed to preserve sized rolled products at any stage of the production process, as well as to preserve metal parts and finished products during storage, transport, and use. __________ Translated from Metallurg, No. 8, pp. 73–74, August, 2006.     

Plasma Etching for Sub-45-nm TaN Metal Gates on High-k Dielectrics

Etching of TaN gates on high-k dielectrics (HfO₂ or HfAlO) is investigated using HBr/Cl₂ chemistry in a decoupled plasma source (DPS). The patterning sequence includes 248-nm lithography, plasma photoresist trimming, etching of a SiN-SiO₂ hard mask, and photoresist stripping, followed by TaN etching. TaN etching is studied by design of experiment (DOE) with four variables using a linear model with interactions. It is found that at a fixed substrate temperature and wafer chuck power, etch critical dimensions (CD) gain decreases with decreasing HBr/Cl₂ flow rate ratio and pressure and with increasing source power and total gas flow rate. Based on these DOE findings, subsequent optimization is performed and a three-step etching process is developed; a main feature of the process is progressively increasing HBr/Cl₂ flow rate ratio. The optimized process provides etch CD gain within 2 nm and gate profile close to vertical and reliable etch-stop on high-k dielectric. This process is successfully applied to the fabrication of the 40-nm HfAlO/TaN gate stack p-MOSFETs with good electrical parameters     

Method for Studying the Interaction of Dispersed Water with Flame

This paper describes a laboratory method for studying flame suppression by a dispersed water cloud produced by an electrically exploded wire in a thin-wall cylindrical glass capsule filled with water. Experimental results are simulated numerically. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 1, pp. 57–64, January–February, 2006.