WO1998014322A1 - Couches minces de titanate de strontium/baryum dopes et procede de dopage - Google Patents

Couches minces de titanate de strontium/baryum dopes et procede de dopage Download PDF

Info

Publication number
WO1998014322A1
WO1998014322A1 PCT/US1997/018357 US9718357W WO9814322A1 WO 1998014322 A1 WO1998014322 A1 WO 1998014322A1 US 9718357 W US9718357 W US 9718357W WO 9814322 A1 WO9814322 A1 WO 9814322A1
Authority
WO
WIPO (PCT)
Prior art keywords
dopant
film
thin film
doped
donor
Prior art date
Application number
PCT/US1997/018357
Other languages
English (en)
Inventor
Bruce W. Wessels
Stephen R. Gilbert
Original Assignee
Northwestern University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Northwestern University filed Critical Northwestern University
Publication of WO1998014322A1 publication Critical patent/WO1998014322A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
    • C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
    • C23C16/30—Deposition of compounds, mixtures or solid solutions, e.g. borides, carbides, nitrides
    • C23C16/40—Oxides
    • C23C16/409—Oxides of the type ABO3 with A representing alkali, alkaline earth metal or lead and B representing a refractory metal, nickel, scandium or a lanthanide

Definitions

  • the present invention relates to metalorganic deposited, thin films of perovskite oxides, such as barium titanate, strontium titanate, and their solid solutions, doped in-situ during deposition to improve dielectric properties by control of film electrical resistivity and resistance to reduction.
  • perovskite oxides such as barium titanate, strontium titanate, and their solid solutions
  • the perovskite oxides barium titanate (BaTi03), strontium titanate (SrTi03), and their solid solutions (Bal-xSrxTi03 ) are promising candidates for numerous electrical device applications, including but not limited to, dynamic random access memories (DRAM's), ferroelectric random access memories (FRAM's), and insulating layers in high TsubC superconductor multilayer devices.
  • DRAM's dynamic random access memories
  • FRAM's ferroelectric random access memories
  • insulating layers in high TsubC superconductor multilayer devices insulating layers in high TsubC superconductor multilayer devices.
  • dielectric thin films are needed possessing low defect densities and high electrical resistivities (10 13 to 10 14 Ohm-centimeter) for minimizing electrical charge leakage, dc electrical degradation, and ferroelectric fatigue which is the decrease of remanent polarization with increasing switching cycles as described by Chen et al. in J. Appl. Phys . 76, (9), 1 November 1994).
  • the Ba source possesses fluorine, water must be introduced to the coating chamber during deposition to assist in fluorine removal.
  • the accidental incorporation of fluorine or hydrogen into the thin film may introduce accidental donor dopants on the anion sites of the oxide film, leading to detrimental decrease in thin film resistivity and dielectric properties .
  • An object of the present invention is to provide a method of metalorganic chemical vapor deposition of thin perovskite oxide films such as BaTi03, SrTi03, and Bal-xSrxTi03, as well as the thin films produced thereby, in a manner to improve film dielectric properties by control of film electrical resistivity and other film properties such as, for example only, resistance to reduction, accidental donor incorporation, dc electrical degradation, and ferroelectric fatigue.
  • the present invention provides a method of depositing high dielectric perovskite oxide thin films, such as BaTi03, SrTi03, and Bal-xSrxTi03, on a substrate by metalorganic chemical vapor deposition using reduced vapor pressure metalorganic precursors under conditions to provide in-situ doping of the thin film with a dopant of a type and in an amount effective to improve film dielectric properties by control of film electrical resistivity and other film properties such as resistance to reduction, accidental donor incorporation, dc electrical degradation, and ferroelectric fatigue.
  • the thin film can be doped with a net excess of an acceptor dopant, such as for example only, aluminum, or net excess of cation donor dopant, such as for example only the rare earth element lanthanum in accordance with embodiments of the invention.
  • Figure 1 is a graph illustrating leakage current density, J, versus bias voltage properties of undoped SrTi03 and Al doped SrTi03 thin films deposited on Nb:SrTi03 substrates pursuant to the invention.
  • the temperature, T(A1), of the Al precursor source is set forth on Fig. 1 for the samples tested using a magnesium electrical contact area of 1.88xl0 "3 cm 2 .
  • Figure 2 is a graph illustrating the dependence of room temnperature resistivity versus the La(dpm)3 vapor pressure during film deposition of La-doped BaTi03 thin films. The line serves only as a guide through the data shown.
  • Figure 3 is a schematic diagram of apparatus for metalorganic chemical vapor deposition of thin films of the invention.
  • a strontium titanate (SrTi03) thin film was grown or deposited pursuant to an embodiment of the invention by metaloraganic chemical vapor deposition on various substrates including (100)LaA103, (100) Nb:SrTi03 comprising 0.5 weight % Nb doped SrTi03, and oxidized (100) Si.
  • substrates including (100)LaA103, (100) Nb:SrTi03 comprising 0.5 weight % Nb doped SrTi03, and oxidized (100) Si.
  • the invention is not limited to these substrates and other substrates can used.
  • reactants i . e.metalorganic precursors bearing the film components (e.g. strontium, titanuim, acceptor dopant such as aluminum, and oxygen) are provided in a reactor and reacted in proportions and under conditions of temperature and pressure controlled to deposit a strontium titanate thin film that is doped in-situ with aluminum as an acceptor dopant as the film is grown or deposited on the substrate.
  • An acceptor dopant is defined as having a smaller positive charge than the host ion it replaces and thus represents a negative charge relative to the ideal oxide lattice.
  • Other acceptor dopants which may be used in practicing the invention to control electrical resistivity of the thin film include Fe, Ga, Ni, Cr, Co, and Ca.
  • Metalorganic chemical vapor deposition apparatus described by L. A. Wills et al. in J. Crvst. Growth, 107, 712 (1991), the teachings of which are incorporated herein by reference, can be used in the practice of the present invention to deposit the doped strontium and/or barium titanate thin films on suitable substrates.
  • Apparatus to this end is shown schematically in Figure 3 and comprises a low pressure, two-zone horizontal quartz reactor system having a reactor zone that is provided with reactants (metalorganic precursors) in suitable proportions for reaction under the temperature and pressure conditions in the reaction zone to deposit or grow the doped strontium and/or barium titanate thin films on the substrate S.
  • the metalorganic precursors used were high purity (99.999%) and included:
  • the Sr and Al solid sources were placed in separate reactor source zones in the manner shown in Figure 3 and resistively heated.
  • the liquid TPT was stored in a bubbler that was heated by a recirculating bath (not shown) .
  • Argon high purity
  • Oxygen high purity bubbled through deionized water was used as the reactant gas for reacting with the metalorganic precursors.
  • the argon and oxygen flow rates were controlled by mass flow controllers (MFC). Pressure gages P were used at appropriate locations of the apparatus. The reactor pressure was set by the total flow rate.
  • An IR (infrared radiation) lamp was used to heat a SiC coated graphite susceptor SP on which the substrate is placed in the reaction zone to provide an appropriate substrate film growth temperature in the range of 725 to 820 degrees C.
  • the deposition temperature was monitored by chromel-alumel thermocouple placed inside the susceptor. The films were deposited and cooled in an oxygen partial pressure 1.65 to 1.80 Torr .
  • Al doped strontium titanate thin films were grown on single crystal LaA103, (100) Nb:SrTi03, and oxidized Si (100) substrates mentioned above.
  • the deposition conditions used to grow Al doped strontium titanate thin films on the aforementioned substrates are summarized in Table I.
  • Al doped strontium titanate thin films deposited on the (100) LaA103 and (100) Nb:SrTi03 substrates were epitaxial and single phase, while the films grown on oxidized (100) Si were non- textured meaning that they did not have a preferred orientation.
  • the film thicknesses were in the range from 0.1 to 0.7 microns.
  • Al dopant concentrations of the thin films were estimated to range from less than 0.10 atomic percent to approximately 1 atomic percent based upon energy dispersive X-ray analysis and film latttice parameter measurements.
  • Al doped strontium titanate (Al-doped SrTi03) thin films as described above were found to exhibit significant improvements in both dc electrical resistivity and leakage current density over the corresponding undoped thin films.
  • the increase in dc resistivity is demonstrated in Tables II and III.
  • Table II Four probe dc electrical resistivity measured for undoped SrTiOj deposited on LaAlQ3.
  • p room temperature resistivity
  • a lattice constant
  • thickness film thickness
  • FWHM full width at half maximum of the (200) film reflection ( diffractometer data)
  • d film thickness
  • Figure 1 demonstrates that Al doping of the SrTi03 thin films as described above led to a decrease in the leakage current density at an applied bias voltage of +2 volts from approximately 10 " " Ampere/centimeters squared for undoped SrTi03 thin films to about 10 " ⁇ Ampere/centimeters squared for Al-doped SrTi03 thin films, which represents a 10 4 improvement in leakage current density for the Al doped thin films.
  • High resistivity acceptor doped ferroelectric thin films such as doped SrTi03 and BaTi03 as well as their solid solutions can be produced by metalorganic chemical vapor deposition pursuant to the invention.
  • the thin film is doped with a net excess of cation donor impurities.
  • a donor dopant is defined as having a higher positive charge than the host cation it replaces and thus represents a postive charge relative to the ideal oxide lattice.
  • Other donor dopants which may be used in practicing the invention to control electrical resistivity of the thin film include Nb, Ce, Nd, Sm, Eu, Gd, and Ho.
  • the metalorganic precursors used were high purity (99.999%) and included:
  • the Ba and La solid sources were placed in separate reactor source zones similar to the manner shown in Figure 3 for the strontium and aluminum sources and resistively heated.
  • the dopant vapor pressure was controlled by varying the La(dpm)3 temperature between 130 degrees C and 160 degees C and was calculated using data from R.E. Sievers et al . , Science 201, 217 (1978).
  • the liquid TPT was stored in a bubbler that was heated by a recirculating bath (not shown).
  • Argon high purity
  • Oxygen (high purity) bubbled through deionized water was used as the reactant gas for reacting with the metalorganic precursors.
  • argon and oxygen flow rates were controlled by mass flow controllers (MFC) .
  • Pressure gages P were used at appropriate locations of the apparatus.
  • reactor pressure was set by the total flow rate.
  • An IR (infrared radiation) lamp was used to heat a SiC coated susceptor SP on which the substrate is placed in the reaction zone to provide an appropriate substrate film growth temperature in the range of 800 degrees C for a (100) LaA103 single crystal substrate.
  • the deposition temperature was monitored by chromel-alumel thermocouple placed inside the susceptor.
  • the films were deposited and cooled in an oxygen partial pressure of 1.65 to 1.80 Torr.
  • the thin La-doped barium titanate films deposited on the (100) LaA103 substrates were epitaxial and single phase having a (hOO) orientation, indicating that the lattice a-axis was perpendicular to the substrate surface.
  • In-plane epitaxy of the thin films was verified using high resolution transmission electron microscopy (HRTEM).
  • HRTEM transmission electron microscopy
  • the film-substrate interface was found to be nearly atomically abrupt and the lattice mismatch was accommodated by a regular array of misfit dislocations.
  • small islands of amorphous secondary phase, identified as the Ba2Ti04 phase were observed at the film-substrate interface. These amorphous regions, however, did not appear to hinder the subsequent epitaxial film growth.
  • the film thicknesses were in the range from 0.30 to 0.80 micron.
  • Cross-sectional electron energy loss spectroscopy (EELS) and convergent beam electron diffraction anaylsis of the optical and structural properties of the films indicated that the films assumed the bulk characteristics of tetragonal BaTi03 at distances greater than 40 nanometers away from the film-substrate interface.
  • cross-sectional transmission electron microscopy revealed misoriented columnar BaTi03 grains that were 0.2 micron in diameter extending through the thickness of the film. Based on X-ray diffraction results indicating highly oriented films both in the a-axis direction perpendicular to the substrate surface and in the plane of the film, the grain boundaries were low angle in nature with no secondary phases observed at the grain boundaries.
  • the La-doped BaTi03 thin films were specular in appearance and transparent. Atomic force microscopy measurements indicated a root mean square surface roughness on the order of 10 to 20 nanometers. The films were found to be uniform over a large area and to possess a fine granular morphology presumably resulting from the formation of columnar sub-grains. The average surface feature size for La-doped and undoped BaTi03 thin films was 0.2 to 0.3 microns in diameter.
  • the room temperature dc electrical resistivity of the undoped BaTi03 thin films grown using the high purity Ba precursor described above ranged between 10 5 to 5 X 10 7 Ohm-centimeter, while that of undoped stochiometric material is approximately 10 10 Ohm-centimeter and higher.
  • the room temperature resistivity decreases to a minimum of 55 Ohm-centimeter, Figure 2.
  • the low resistivity of the films is attributed to substitution of trivalent La *3 donors for the divalent Ba +2 cation, creating LaBa + donor centers, although Applicants do not wish to be bound by this explanation.
  • La concentration in the low resistivity La-doped BaTi03 thin films were made by measuring film lattice paramters.
  • the difference in lattice parameters between doped and undoped films therefore falls within plus or minus 0.002 Angstrom standard deviation. This indicated that the La concentration was less than approximately 0.6 atomic % in the semiconducting films based on lattice parameter data for LaxBal-xTi03 from Eylem et al . , Chem. Mater. 4, 1038 (1992).
  • rare earth La dopant Although the embodiment of the present invention involving doping with a net excess of cation donors has been described hereabove with respect to the rare earth La dopant, the invention it is not so limited and can be practiced using other rare earth dopants including but not limited to Ce, Nd, Sm, Eu, Gd, and Ho alone or in combination as well as non-rare earth dopants such as Nb.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Chemical Vapour Deposition (AREA)

Abstract

L'invention concerne un procédé de dépôt sur un substrat de couche minces d'oxyde de péroksvite à grande constante diélectrique, du type BaTiO3, SrTiO3 et Ba1-xSrxTiO3, par dépôt chimique métallo-organique en phase vapeur au moyen de précurseurs métallo-organiques à faible pression de vapeur, dans des conditions permettant le dopage in-situ de la couche mince au moyen d'un dopant d'un certain type et en quantité efficace pour que les propriétés diélectriques de la couche soient améliorées par la modification de la résistivité électrique de la couche, et éventuellement d'autres propriétés de la couche telles que la résistance à la réduction, à l'insertion accidentelle de donneurs, à la dégradation électrique CC et à la fatigue ferroélectrique. La couche mince peut être dopée au moyen d'un excédent net d'un dopant accepteur, tel que par exemple, de l'aluminium, ou un excédent net de dopant donneur cationique, tel que par exemple seulement l'élément du groupe des terres rares, le lanthane, selon les modes de réalisation de l'invention.
PCT/US1997/018357 1996-10-04 1997-10-02 Couches minces de titanate de strontium/baryum dopes et procede de dopage WO1998014322A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US72621096A 1996-10-04 1996-10-04
US08/726,210 1996-10-04

Publications (1)

Publication Number Publication Date
WO1998014322A1 true WO1998014322A1 (fr) 1998-04-09

Family

ID=24917653

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1997/018357 WO1998014322A1 (fr) 1996-10-04 1997-10-02 Couches minces de titanate de strontium/baryum dopes et procede de dopage

Country Status (1)

Country Link
WO (1) WO1998014322A1 (fr)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0960869A2 (fr) * 1998-05-28 1999-12-01 Sharp Kabushiki Kaisha Compositions diélectriques stables à une réaction de réduction et mémoires RAM dynamiques comprenant de telles compositions diélectriques
KR20020079045A (ko) * 2001-04-12 2002-10-19 김상섭 누설전류 억제 구조의 메모리 소자
DE10325629A1 (de) * 2003-03-21 2004-10-07 Forschungszentrum Jülich GmbH Verfahren zur Abscheidung von Verbindungen auf einem Substrat mittels metallorganischer Gasphasendeposition
CN100369222C (zh) * 2004-07-13 2008-02-13 中国科学院物理研究所 在硅片上外延生长掺杂锰酸镧薄膜异质结材料的制备方法
CN100438113C (zh) * 2002-09-27 2008-11-26 中国科学院物理研究所 巨磁阻器件单元阵列式排列的掺杂钛酸钡巨磁阻器件及制法
CN100438114C (zh) * 2002-09-27 2008-11-26 中国科学院物理研究所 阵列式排列的掺杂钛酸锶和掺杂镧锰氧巨磁阻器件及制法
WO2014143880A1 (fr) 2013-03-15 2014-09-18 Siluria Technologies, Inc. Catalyseurs pour une catalyse pétrochimique
WO2017019790A1 (fr) * 2015-07-27 2017-02-02 Northwestern University Films minces épitaxiaux de titanate de baryum faisant intervenir un précurseur de ba(hfa)2 triglyme hautement volatil
US11000835B2 (en) 2014-09-17 2021-05-11 Lummus Technology Llc Catalysts for natural gas processes
US11078132B2 (en) 2011-11-29 2021-08-03 Lummus Technology Llc Nanowire catalysts and methods for their use and preparation
CN113517365A (zh) * 2021-07-09 2021-10-19 西安电子科技大学 一种基于透明氧化物的光电类突触器件及其应用
US11370724B2 (en) 2012-05-24 2022-06-28 Lummus Technology Llc Catalytic forms and formulations
US11795123B2 (en) 2011-05-24 2023-10-24 Lummus Technology Llc Catalysts for petrochemical catalysis

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
APPL. PHYS. LETT., 65(1), July 1994, BLOCK et al., "Photoluminescence Properties of Er3+ -Doped BaTi03 Thin Film", page 25. *
FERROELECTRICS, Vol. 116, 1991, SMYTH, "Charge Motion in Ferroelectric. Thin Films", pages 117 and 119-121. *
J. APPL. PHYS., 76(9), November 1994, CHEN et al., "Compositional Control of Ferroelectric Fatique In Perovskite, Ferroelectric Ceramics and Thin Films", pages 5394-5395. *
THE 188TH MEETING OF THE ELECTROCHEMICAL SOCIETY, 8-13 Oct. 1995, GILBERT et al., "Doped SrTiO3 Dielectric Thin Films Prepared by Metalorganic Chemical Vapor Deposition". *

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0960869A2 (fr) * 1998-05-28 1999-12-01 Sharp Kabushiki Kaisha Compositions diélectriques stables à une réaction de réduction et mémoires RAM dynamiques comprenant de telles compositions diélectriques
EP0960869A3 (fr) * 1998-05-28 2001-10-17 Sharp Kabushiki Kaisha Compositions diélectriques stables à une réaction de réduction et mémoires RAM dynamiques comprenant de telles compositions diélectriques
KR20020079045A (ko) * 2001-04-12 2002-10-19 김상섭 누설전류 억제 구조의 메모리 소자
CN100438113C (zh) * 2002-09-27 2008-11-26 中国科学院物理研究所 巨磁阻器件单元阵列式排列的掺杂钛酸钡巨磁阻器件及制法
CN100438114C (zh) * 2002-09-27 2008-11-26 中国科学院物理研究所 阵列式排列的掺杂钛酸锶和掺杂镧锰氧巨磁阻器件及制法
DE10325629A1 (de) * 2003-03-21 2004-10-07 Forschungszentrum Jülich GmbH Verfahren zur Abscheidung von Verbindungen auf einem Substrat mittels metallorganischer Gasphasendeposition
CN100369222C (zh) * 2004-07-13 2008-02-13 中国科学院物理研究所 在硅片上外延生长掺杂锰酸镧薄膜异质结材料的制备方法
US11795123B2 (en) 2011-05-24 2023-10-24 Lummus Technology Llc Catalysts for petrochemical catalysis
US11078132B2 (en) 2011-11-29 2021-08-03 Lummus Technology Llc Nanowire catalysts and methods for their use and preparation
US11370724B2 (en) 2012-05-24 2022-06-28 Lummus Technology Llc Catalytic forms and formulations
US10865166B2 (en) 2013-03-15 2020-12-15 Siluria Technologies, Inc. Catalysts for petrochemical catalysis
WO2014143880A1 (fr) 2013-03-15 2014-09-18 Siluria Technologies, Inc. Catalyseurs pour une catalyse pétrochimique
US11000835B2 (en) 2014-09-17 2021-05-11 Lummus Technology Llc Catalysts for natural gas processes
US11060184B2 (en) 2015-07-27 2021-07-13 Northwestern University Epitaxial barium titanate thin films using a highly volatile Ba(hfa)2 triglyme precursor
WO2017019790A1 (fr) * 2015-07-27 2017-02-02 Northwestern University Films minces épitaxiaux de titanate de baryum faisant intervenir un précurseur de ba(hfa)2 triglyme hautement volatil
CN113517365A (zh) * 2021-07-09 2021-10-19 西安电子科技大学 一种基于透明氧化物的光电类突触器件及其应用

Similar Documents

Publication Publication Date Title
US7732067B2 (en) Epitaxial layer structures and precursors for topotactic anion exchange oxide films
US5801105A (en) Multilayer thin film, substrate for electronic device, electronic device, and preparation of multilayer oxide thin film
US6270908B1 (en) Rare earth zirconium oxide buffer layers on metal substrates
Iijima et al. Preparation of ferroelectric BaTiO3 thin films by activated reactive evaporation
Lettieri et al. Epitaxial growth of non-c-oriented SrBi 2 Nb 2 O 9 on (111) SrTiO 3
US6121647A (en) Film structure, electronic device, recording medium, and process of preparing ferroelectric thin films
Imada et al. Epitaxial growth of ferroelectric YMnO3 thin films on Si (111) substrates by molecular beam epitaxy
Hwang et al. Deposition and characterization of ZrO2 thin films on silicon substrate by MOCVD
JP3310881B2 (ja) 積層薄膜、電子デバイス用基板、電子デバイスおよび積層薄膜の製造方法
WO1998014322A1 (fr) Couches minces de titanate de strontium/baryum dopes et procede de dopage
Kijima et al. New low-temperature processing of metalorganic chemical vapor deposition-Bi4Ti3O12 thin films using BiOx buffer layer
Yoshida et al. Surface morphology and growth mechanism of YBa2Cu3O7− y films by metalorganic chemical vapor deposition using liquid sources
US6605151B1 (en) Oxide thin films and composites and related methods of deposition
US20160068990A1 (en) Methods of forming perovskite films
JPH10223476A (ja) 強誘電体薄膜およびその製造方法
Vispute et al. Heteroepitaxial structures of SrTiO3/TiN on Si (100) by in situ pulsed laser deposition
Nagano et al. Electrical properties of semiconductive Nb-doped BaTiO 3 thin films prepared by metal–organic chemical-vapor deposition
Yamaguchi et al. Effect of grain size on Bi4Ti3O12 thin film properties
Kim et al. Substrate temperature dependence of phase and orientation of pulsed laser deposited Bi–La–Ti–O thin films
Wu et al. Epitaxial and highly electrical conductive La 0.5 Sr 0.5 TiO 3 films grown by pulsed laser deposition in vacuum
Kim et al. Growth of bismuth silicate films on Si and its dielectric properties
Sun et al. Oriented bismuth titanate thin films by single-solid-source metal-organic chemical vapour deposition
Hironaka et al. Preparation of Ultra thin SrBi2Ta2O9 Films Using Metalorganic Chemical Vapor Deposition Combined with a Modified Annealing Method
Selbmann et al. Structural properties of epitaxial YSZ and doped CeO2 films on different substrates prepared by liquid sources MOCVD (LSMOCVD)
Kaiser et al. Effect of film composition on the orientation of (Ba, Sr) TiO 3 grains in (Ba, Sr) y TiO 2+ y thin films

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): CA JP KR SG

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 1998516986

Format of ref document f/p: F

122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: CA