Showing papers on "Atomic layer deposition published in 1992"

Preparation of thin films

Abstract: Vacuum Evaporation Sputtering Ion Beam and Ion-Assisted Deposition Reactive Deposition Techniques Ionized Cluster Beam Methods Chemical Methods of Film Deposition Epitaxial Film Deposition Techniques Other Methods of Film Deposition Summary

Self-aligned silicide technology for ultra-thin SIMOX MOSFETs

Abstract: The salicide technology using rapid thermal annealing was applied to MOSFETs on thin-film SOI. Since the SOI film was limited to a thickness of less than 100 nm, the silicidation reaction between Ti and Si atoms on the SOI surface exhibited new features that depended on the initial thickness of the deposited Ti. There was an optimum thickness of as-deposited Ti on silicidation due to the restricted thickness of the Si layer. Beyond the optimum point, the region adjacent to the silicided Si layer works as a Si source to assure stoichiometric TiSi/sub 2/. The subthreshold slopes and carrier mobilities were not changed by the salicide process. Junction leakage characteristics were slightly degraded; however, the change was small enough for device application. The influence on AC characteristics was well demonstrated for a high-speed CMOS ring oscillator with a gate length of 0.7 mu m. The minimum delay time/stage was 46 ps/stage at 5 V. This gives 1.8 times higher speed operation than the controlled bulk CMOS ring oscillators with the same design rule. >

Ultra-thin-base Si bipolar transistor using rapid vapor-phase direct doping (RVD)

Abstract: A novel doping method called rapid vapor-phase direct doping (RVD) is developed to form ultra-shallow junctions. The base region of a conventional bipolar transistor is formed by this method, and in ultra-narrow 25-nm base is obtained. The Gummel plot of this device shows almost ideal characteristics. This result suggests that this method does not induce any defects which cause a leakage current. RVD is a thermal diffusion method using hydrogen as a carrier gas and B/sub 2/H/sub 6/ as a source gas. In this method, the impurity atoms directly diffuse from the vapor phase into silicon by a rapid thermal process without a boron-glass layer or metallic boron layer. By varying the source gas flow rate, doping time, and temperature, ultra-shallow junctions below 40 nm with controlled surface concentrations are successfully formed. An ultra-shallow 20-nm junction with surface boron concentration of 4*10/sup 18/ cm/sup -3/ is obtained at 800 degrees C for 5 min with B/sub 2/H/sub 6/ flow rate of 30 ml/min. >

Formation of compound semiconductors by electrochemical atomic layer epitaxy

Abstract: A method for the electrochemical formation of epitaxial deposits of compound semiconductors is being developed. It is referred to as electrochemical atomic layer epitaxy (ECALE). The method is the electrochemical analog of atomic layer epitaxy (ALE), where ALE is a method used to form compounds by alternately depositing atomic layers of the constituent elements. Atomic layers are formed in ECALE by using underpotential deposition (UPD). UPD is a phenomena where an atomic layer of an element deposits at a potential prior to that needed to deposit the bulk element, due to the increased stability afforded by reaction with a second element present at the substrate surface. This paper describes the structure of the first monolayer of Te formed on an Au(100) surface and the structure of a monolayer of CdTe, subsequently formed by deposition of an atomic layer of Cd. Deposits have been formed and analyzed in an ultrahigh vacuum (UHV) surface analysis instrument directly coupled to an electrochemical cell. Low‐en...

Atomic layer epitaxy of III-V compounds: chemistry and applications

Abstract: Atomic layer epitaxy (ALE) of III-V compounds is addressed, with particular focus on ALE by chloride source gases of group III elements and hybrids of group V elements. A self-limiting growth mechanism in ALE is the most significant advantage over other epitaxial methods. To realize this mechanism, selections of source gases and the reactor gases and the reactor design are described. The chemistry and growth kinetics of ALE, which also provide interesting information for understanding other vapor phase epitaxy (VPE) processes, are discussed, and a model of the self-limiting growth mechanism for chloride ALE is proposed. As a promising application of ALE, the growth of fine structures using sidewall epitaxy and selective area growth is demonstrated. Prospects for the future are briefly discussed. >

Laser ablation and deposition of metals

Abstract: • A submitted manuscript is the version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers.

Implementation of a TiN cap layer into conventional self-aligned RTP titanium disilicide MOS process

Abstract: The silicide growth over the spacers (bridging) in the conventional self-aligned silicide process using titanium disilicide is dominated by the lateral diffusion of Si atoms from the gate and source/drain areas. A TiN cap layer, which has been suggested to minimize the bridging problem was studied. The influence of such a capping layer on the reaction between Ti and Si, on the lateral diffusion of Si, and on the electrical properties of the TiSi 2 -Si contact was investigated.

One-dimensional conjugated polymer film and quantum well fabrication by molecular layer deposition (MLD) and chemical vapor deposition

Abstract: We demonstrate the deposition of one-dimensional conjugated polymers, the formation of quantum wells by chemical vapor deposition. We also propose molecular layer deposition (MLD), in which molecules are stacked on substrates one by one in order of preference in a vacuum. We found MLD to be useful in the fabrication of conjugated polymers.

Quantum Well Formation in One-Dimensional Polymer Films by Molecular Layer Deposition and Chemical Vapor Deposition

Abstract: Quantum wires and dots were fabricated in one-dimensional conjugated polymer films by chemical vapor deposition. In the wires, a sharp exciton absorption peak, and in the dots, a blue shift in the absorption band due to electron confinement were observed. We showed that acceptors could be substituted into the conjugated polymer chain. We also demonstrated that molecular layer deposition (MLD), in which molecules are stacked on substrates one by one in order of preference in a vacuum, is feasible in fabricating one-dimensional conjugated polymers.

Deposition of Superconducting Tl-Ba-Ca-Cu-O Phases on Metal Foils by Metal-Organic Chemical Vapor Deposition

Abstract: The synthesis of superconducting Tl-Ba-Ca-Cu-O thin films on metal foils (Au and Ag) by metal-organic chemical vapor deposition (MOCVD) has been investigated. Ba-Ca-Cu-O-(F) films are first prepared via MOCVD using fluorinated "second generation" metal-organic precursors. After an intermediate anneal with water vapor-saturated oxygen to promote removal of F, Tl is introduced by annealing in the presence of a mixture of oxides (Tl2O3, BaO, CaO, CuO) of a specific composition. Characterization of the thin films by scanning electron microscopy, EDX, x-ray diffraction, and variable temperature magnetization measurements has been carried out. High temperature superconductor (HTS) films of Tl2Ba2Ca1Cu2O8-x on Au foil exhibit a magnetically derived Tc = 80K and a high degree of texturing with the crystallite c-axes oriented perpendicular to the substrate surface as evidenced by enhanced (000 x-ray diffraction reflections. Thin film coverage on Ag foil becomes non-contiguous during the (Tl2O3, BaO, CaO, CuO) mixture anneal.

Deposition Rate and Surface Smoothness of Fe 3 O 4 Films Prepared by Light-Enhanced Ferrite Plating

Abstract: Polycrystalline Fe 3 O 4 films were deposited by ferrite plating, irradiating the substrate surface with a Xe-lamp (350 W) and using FeCl 2 and NaNO 2 as the reaction and oxidizing solutions, respectively. When the concentration of FeCl 2 was high, the film surface was rough, with particle of 0.2~0.4 ?m in size. As the concentration of FeCl 2 decreased the film surface smoothness improved, but the film deposition rate decreased. Addition of dextran ((C 6 H 10 O 5 ) n , n= 1200~1800) to the reaction solution improved the film surface smoothness without significantly lowering the deposition rate.