Showing papers on "Pulsed laser deposition published in 1983"

Method for growing silicon-including film by employing plasma deposition

Abstract: A method for growing a silicon-including film is disclosed in which the above film is grown on a surface of a substrate by using, as a discharge gas, a halogenide silicon gas or a gas mixture containing a halogenide silicon gas in a plasma deposition apparatus including a vacuum chamber, means for supplying microwave power to the vacuum chamber, means for forming a magnetic field in at least part of the vacuum chamber, means for introducing the discharge gas into the vacuum chamber, and means for holding the substrate within the vacuum chamber.

Laser induced chemical vapor deposition of Ni by decomposition of Ni(CO)4

Abstract: Polycrystalline Ni has been grown by decomposition of Ni(CO)4 using different wavelengths of the visible radiation of a Kr+ laser. The influence of laser irradiance, substrate material and scanning velocity on deposition rate and widths of patterns has been investigated. The deposition rates achieved are typically several μm/s, and the lateral dimensions of the deposits can be as small as 1 μm.

Laser chemical vapor deposition of selected area Fe and W films

Abstract: Localized deposition of thin films of W and Fe in both spot and line geometries has been demonstrated by laser chemical vapor deposition using a CO2 laser and several different gaseous reactants. Although optical self‐limiting of the deposit thickness was observed under some irradiation conditions, films several thousand A thick could be deposited with good physical properties. Radial dimensions were less than or equal to the laser beam diameter (D1/e2 =600 μm).

Chemical Vapor Deposition of PbTiO3Thin Film

Abstract: A PbTiO3 thin film has been grown on Pt or Pt-coated Si wafer by chemical vapor deposition instead of rf sputtering which makes a surface of substrate damaged. As the source material of the deposition, two kinds of combinations of (PbCl2 and TiCl4) and (PbO and Ti(C4H9O)4) have been tried to know the effect of chlorine inclusion in the PbTiO3 network. The surface of the film is much smoother than that of the film prepared by the rf sputtering, and deposition rate is several µm/hr. The deposited film structure is mostly oriented to or direction which depends on the source material and the deposition condition. The maximum dielectric constant of the film is 130, and D-E hysteresis characteristic has been also obtained.

Laser Induced Chemical Vapor Deposition

Abstract: Chemical vapor deposition (CVD) is a widely used technique for the production of thin films of metals, semiconductors, and insulators [1]. In the standard procedure the chemical reaction is thermally activated near or on the hot surface of the substrate, where deposition takes place. Normally, the substrate is directly and uniformly heated and one obtains an extended uniform film of the deposited material. In contrast to this standard CVD technique, laser-induced chemical vapor deposition (LCVD) allows local deposition of materials within the focus of a laser. Therefore, LCVD may become an alternative method in cases where at present material patterns are produced by standard CVD techniques and photolithographic methods.. While the production of microstructures according to these standard techniques requires several different steps, LCVD allows one-step deposition or direct writing of structures with lateral dimensions down to at least 1 µm. Because of the high deposition rates achieved in pyrolytic LCVD, the production of three-dimensional structures of micron size is also possible.

Selected area growth of InP by low pressure metalorganic chemical vapor deposition on ion implanted InP substrates

Abstract: InP deposition by metalorganic chemical vapor deposition on implanted substrates has different qualities according to the damage density of the substrate surface induced by the bombardment. For low damage densities, the layer deposited is monocrystalline. For middle damage densities, the deposition is composed of nuclei. For high damage densities, there is no deposition on the implanted surface, and in this case, we observe a material transport. By using the ion implantation technique in conjuntion with metalorganic chemical vapor deposition, it is possible to have selective area growth of InP.

Plasma enhanced beam deposition of thin films at low temperatures.

Abstract: A plasma enhanced beam deposition technique for thin films is discussed. It is shown that thin films of tailored stoichiometry or amorphous layers can be easily deposited in the temperature range (30–250 °C). The technique uses a combination of active atomic or molecular beams generated by charged particles or photons. Films of SiO2, Al2O3, ZrO3, silicon oxynitride, NbN, etc., have been deposited on metals, semiconductors, and insulators. The interfaces between the deposited films and the substrates are extremely sharp and no native growth of oxides of nitrides occurred on the substrate surfaces during film deposition. Film thickness and composition can be precisely controlled by optical monitoring techniques. For instance, the physical properties of the deposited SiO2 at 100 °C is nearly identical to that of thermal oxides grown on Si at 1100 °C. The deposited SiO2 has an electrostatic breakdown field strength of about 5×106 V/cm, and 1 MHz C–V curves show a hysteresis of 50 mV at a sweep rate of 100 mV/...

Energy Deposition and Heat Flow for Pulsed Laser, Electron and Ion Beam Irradiation

Abstract: Energy deposition in times as short as tens of nanoseconds, with densities of joules/cm2, has emerged in the last few years as a new way of modifying the near surface structures of materials. The initial input came from the use of Q-switched laser pulses to anneal damage in ion implanted semiconductors. Interest in other areas, such as metallurgy, is now growing because of the possibility of forming new phases or new structures. The history of this field is reported in the proceedings of the annual meetings of the Materials Research Society dedicated to this subject since 1978 (Ferris et al., 1979; White and Peercy, 1980; Gibbons et al., 1981).

Chemical vapor deposition apparatus and process

Abstract: A chemical vapor deposition device having uniformly distributed heating means (8,10) substantially surrounding an inner deposition reaction chamber (18) for providing isothermal or precisely controlled gradient temperature conditions therein, the reaction chamber being surrounded by the walls of an outer vacuum chamber (2). A purging gas may be introduced into the vacuum chamber to prevent leakage of reactant gas from the reaction chamber.

Laser-Induced Chemical Vapor Deposition of Silicon Nitride Films

Abstract: Films of silicon nitride have been deposited using a continuous wave CO2 laser to excite gaseous mixtures of silane and ammonia. A typical deposition rate is 150A/min. The hydrogen film content and its dependence on the substrate deposition temperature are similar to that observed for plasma CVD silicon nitride. The CO2 laser CVD films are silicon rich with a Si/N ratio = 1.2 at a NH3/SiH4 gas flow ratio of 1000. Conformal step coverage is observed on patterned silicon oxide features.

Laser Chemical Vapor Deposition.

Abstract: Laser chemical vapor deposition (LCVD) is an adaptation of conventional CVD using a laser heat source. As shown in Fig. 1, the laser is focused through a transparent window and the transparent gaseous reactants onto an absorbing substrate, creating a localized hot spot at which the deposition reaction takes place.

Method for the deposition of high-quality crystal epitaxial films of iron

Abstract: A method for forming a single crystal epitaxial film of a selected metal on the surface of a substrate. The method includes the steps of positioning the substrate in an ultra high vacuum environment and exposing the substrate surface to a metalorganic vapor including ions of the selected metal while maintaining an ultra high vacuum environment.

Chemical Vapor Deposition of Silicon Films by Pulsed CO2 Laser Irradiaton of Silane

Abstract: Silane molecules have been irradiated by a pulsed CO2 laser operating at 10.59 µm. The threshold of silicon formation by homogeneous dissociation of silane has been investigated as a function of laser fluence (0.1–3.5 J/cm2) and silane pressure (1–100 Torr). Silicon films have been deposited on quartz substrates using the laser beam either perpendicular or parallel to the substrate surface. The crystallographic structure and deposition rate of these silicon films are found to be dependent on the incident angle of the laser beam, silane pressure, substrate temperature and laser fluence. The growth mechanism of these films is discussed.

Electrical and structural properties of pulse laser-annealed polycrystalline silicon films

Abstract: Doped epitaxial films of Si on single-crystal high-resistivity Si substrates have been prepared using ion implantation and Q-switched ruby laser annealing of LPCVD polycrystalline Si layers. Films, doped with B or As in the range 1017to 5 × 1020cm-3were studied by the measurement of their resistivities, Hall mobilities, and doping density profiles. The good film quality achieved permitted the fabrication of p-channel MOS transistors which, through measurements of threshold voltage and transconductance, yielded additional data on the surface mobility and the integrity of the Si-SiO 2 interface. The electrical properties of the films compared favorably with those of similarly doped single-crystal material, and transmission electron microscopy was used to confirm the good structural quality of the epitaxial growth.

Limiting and Enhancement Effects in Laser Chemical Vapor Deposition

Abstract: Laser chemical vapor deposition (LCVD) is a modification of conventional CVD using a laser heat source. The film growth characteristics differ considerably from conventional CVD in several ways, however. The use of an optical heat source means that the optical properties of the film/substrate system must be considered, e.g., for metals deposited on absorbing substrates, the film thickness and diameter may “self-limit” in some cases because the deposited film reflects most of the laser energy. On the other hand, the small area heated in LCVD results in a different diffusion geometry and access to higher surface temperatures than are achievable when large areas are heated. For favorable reactant systems, these enhancement effects can yield fast deposition rates and line deposition scan speeds greater than 10 cm/sec. This paper will review results of pulsed and cw LCVD of predominantly metal films using visible and infrared lasers.

Rrocess of annealing by compound beams

Abstract: PURPOSE:To make the low temperature process feasible eliminating undesirable substrate heating operation by a method wherein both pulse laser beams and pulse electronic beams are simultaneously controlled for radiation. CONSTITUTION:The applicable laser must not be CW laser for conventional laser annealing and the electronic beams must be pulses beams so as to make them synchronize with the pulse laser. It is desirable to control the pulse scanning so that the diameter of electronic beam 1 may overlap by 50%. It is also important that the pulse 1 in the electronic beam 1 is synchronized with the pulse 2 of laser beam within the time interval of the pulse 2 otherwise the heating by YAG laser becomes meaningless in terms of the properties of instantaneous heating and cooling. When the oxidizing the surface layer of silicon wafer under said conditions, the silicon layer settled by CVD is processed by annealing, multiple crystal layer with thickness of scores mum is produced.

Laser Induced Chemical Vapour Deposition

Abstract: this potential. In order to maintain the necessary continuity of the principal re­ search efforts, priorities and especially posteriorities should be applied gradually, even though fast action may sometimes be required for priorities having only a short life-span. Research councils dispose of several means for putting research priorities into practice. Depending on specific needs, the following principal instruments are em­ ployed : co-ordinated cooperation, national research programmes, international cooperation and fellowship programmes.

Thin Film Deposition Techniques

Abstract: As already pointed out in Chapter 1, a deposition technique and its associated process parameters have a characteristic effect on the nucleation- and growth-dominated microstructure of a thin film and thereby on its physical properties. Two-dimensional materials of thicknesses ranging from angstroms to hundreds of micrometers can be prepared by a host of so-called thin film as well as thick film techniques. The latter methods involve the preparation of thin materials from a paste or liquid form of the bulk material. The two sets of techniques yield thin film materials of widely different microstructures and properties.

Manufacture of thin carbide film

Abstract: PURPOSE:To form a thin carbide film contg. little impurities on the surface of a substrate to be converted to a carbide by irradiating pulse laser light on the surface of the substrate having a thin carbon film deposited thereon to cause a carbide forming reaction. CONSTITUTION:Carbon 5 is deposited on a substrate 4 to be converted to carbide in about 0.1-100mum thickness by vacuum deposition or other method. This substrate 4 is mounted on a support 3 and pulse laser light is irradiated on the surface at about 10nsec pulse width. By the irradiation the temp. of the carbon film 5 on the surface of the substrate 4 and the temp. of the substrate 4 rise, and the carbon 5 and the substrate 4 are melted and reacted to form the carbide of the substrate 4 on the surface of the substrate 4. By this method the carbide forming reaction is finished in a short time and a high-quality thin carbide film contg. little impurities can be formed.

Ionized cluster beam deposition

Abstract: Ionized Cluster Beam (ICB) deposition, a new technique originated by Takagi of Kyoto University in Japan, offers a number of unique capabilities for thin film metallization as well as for deposition of active semiconductor materials. ICB allows average energy per deposited atom to be controlled and involves impact kinetics which result in high diffusion energies of atoms on the growth surface. To a greater degree than in other techniques, ICB involves quantitative process parameters which can be utilized to strongly control the characteristics of films being deposited. In the ICB deposition process, material to be deposited is vaporized into a vacuum chamber from a confinement crucible at high temperature. Crucible nozzle configuration and operating temperature are such that emerging vapor undergoes supercondensation following adiabatic expansion through the nozzle.

Vacuum Methods For Layer Deposition And Application To Device Structures

Abstract: This paper reviews the deposition methode of single element metallic films, refractory films, silicides, vacuum epitaxy of metallic films, silicon and GaAs. The vacuum deposition techniques are: rf sputtering, magnetron sputtering, e-beam deposition, vacuum epitaxy and molecular beam epitaxy. Finally, the application of these films to microwave devices and integrated circuits is reviewed.

Low-power multi-pulse laser annealing of α-Ge

Abstract: In this paper we want to show by means of Reflection High Energy Electron Diffraction (RHEED) techniques that the recrystallization processes taking place on amorphous germanium films irradiated with low-power superimposed ruby laser pulses occur gradually. Furthermore, in implanted α-Ge films the amorphous-crystalline front moves from the surface of the specimen towards the substrate, while the opposite occurs for glow-discharge deposited films. Moreover, electron microscope observations carried out with a double-stage carbon replica technique at different depths in the specimen show that defect migration is one of the competitive mechanisms in low-power laser annealing.