JP3845718B2 - Novel crystallinity, orientation, and surface smoothness control method of bismuth-based layered perovskite SrBi2Ta2O9 thin film by ultraviolet irradiation - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a bismuth-based layered perovskite ferroelectric thin film for controlling crystallinity, orientation, and surface smoothness. More specifically, the present invention relates to a novel process that incorporates a photochemical reaction into the production process. The present invention relates to a method for controlling crystallinity, orientation, and surface smoothness of a bismuth-based layered perovskite SBT thin film.
[0002]
[Prior art]
SrBi ₂ Ta ₂ O ₉ (SBT), which is one of the layered perovskite compounds, is known to have excellent ferroelectricity, piezoelectricity, pyroelectricity and the like due to its unique crystal structure. This material is attracting attention as a ferroelectric memory material (references [1, 2]). A ferroelectric memory is composed of a ferroelectric thin film and a silicon semiconductor integrated circuit. Since the ferroelectric thin film fabrication process is performed after the CMOS device process, it has been reported that silicon devices are sometimes severely damaged during the heat treatment process (reference [3-5]). Therefore, it is necessary to lower the temperature of the ferroelectric thin film synthesis process in order to prevent an interface reaction between the ferroelectric thin film and silicon or an electrode material.
[0003]
By the way, various methods such as a sputtering method, a sol-gel method, a chemical vapor deposition method (CVD), and a metal organic thermal decomposition method (MOD) are used for producing a ferroelectric thin film (reference [6]. , 7]). Among these methods, the present inventors have stoichiometrically (Sr: Bi: Ta) three kinds of metal elements, Sr, Bi and Ta, which are precursors of an SBT thin film by a sol-gel method. = 1: 2: 2), a new low-temperature synthesis method of Sr-Bi-Ta triple alkoxides has been developed and reported (References [8, 9]). Since the atomic arrangement of the SBT thin film precursor obtained by this method coincides with the sublattice of the SBT crystal (Reference [8-10]), the SBT thin film can be crystallized at a lower temperature.
[0004]
Further, in order to develop excellent ferroelectric characteristics in this thin film, a technique for accurately controlling the crystallinity and orientation is required. In order to reduce the size of the device, it is important to control the surface microstructure, that is, to control the surface smoothness. In particular, the C-axis oriented SBT thin film with good crystallinity is applied to a comb-shaped microelectromechanical system (MEMS) using an electrode parallel to the polarization axis direction, and exhibits an orientation tilted from the C-axis direction. The SBT thin film is useful when an electrode is attached perpendicular to the polarization axis as in a ferroelectric memory.
[0005]
[Problems to be solved by the invention]
So far, as a method for controlling the crystallinity and orientation of the thin film, a method of introducing a new layer such as a seed layer or a buffer layer between the thin film and the substrate has been reported (Reference [11]). However, in any case, there is a possibility that the process becomes complicated due to an increase in the number of layers, and that the electrical characteristics are deteriorated due to an increase in the interface reaction.
Therefore, the present inventors introduced a photochemical reaction into the manufacturing process, and as a result, attempted to control the crystallinity, orientation, and surface smoothness of the bismuth-based layered perovskite thin film more efficiently and simply. Succeeded in the development of a novel control method for crystallinity, orientation and surface smoothness of SBT thin films, thereby completing the present invention.
[0006]
[Means for Solving the Problems]
The present invention for solving the above-described problems comprises the following technical means.
(1) A partially hydrolyzed Sr—Bi—Ta triple alkoxide (an organic functional group containing Sr [BiTa (OR) ₉ ] ₂ , R: C, H, O) is used as a precursor solution on a substrate with a Pt electrode. A method for controlling crystallinity / orientation / surface smoothness of a bismuth-based layered perovskite SBT thin film, wherein the coated SrBi ₂ Ta ₂ O ₉ (SBT) thin film is irradiated with ultraviolet rays.
(2) SrBi ₂ Ta ₂ O ₉ (SrBi ₂ Ta ₂ O ₉₎ before crystallization coated on a substrate with a Pt electrode using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution. The method for controlling crystallinity, orientation, and surface smoothness of a bismuth-based layered perovskite SBT thin film according to (1), wherein the SBT thin film is irradiated with ultraviolet rays at room temperature using an ultrahigh pressure mercury lamp.
(3) Using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution, an SBT thin film coated on a substrate with a Pt electrode is coated with a low pressure mercury lamp. The method for controlling crystallinity / orientation of a bismuth-based layered perovskite SBT thin film according to (1), wherein the ultraviolet irradiation is performed at room temperature.
(4) Using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution, a low-pressure mercury lamp is applied to the SBT thin film before crystallization coated on a substrate with a Pt electrode. The method for controlling the surface smoothness of a bismuth-based layered perovskite SBT thin film according to (1), wherein the method is used for ultraviolet irradiation at room temperature.
(5) Using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution, an SBT thin film before crystallization coated on a substrate with a Pt electrode is applied to an ultrahigh pressure mercury lamp. The method for controlling crystallinity / orientation of a bismuth-based layered perovskite SBT thin film according to (1) above, wherein ultraviolet irradiation is performed using 150 at a temperature of 150 ° C.
(6) An ultra-high pressure mercury lamp is applied to a pre-crystallized SBT thin film coated on a Pt electrode substrate using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution. The method for controlling the surface smoothness of a bismuth-based layered perovskite SBT thin film according to (1) above, wherein UV irradiation is performed under a temperature condition of 150 ° C. using
(7) Using the partially hydrolyzed Sr—Bi—Ta triple alkoxide precursor solution according to any one of (1) to (6) above, Pt is formed by a coating method or a printing method such as dip coating or spin coating. A method for producing a bismuth-based layered perovskite thin film, comprising forming a thin film on the surface of a substrate such as a metal with electrodes, a single crystal of oxide, or a ceramic.
(8) The thin film before crystallization on the substrate with the Pt electrode produced by the light irradiation according to any one of (1) to (6) above is subjected to calcination and rapid heating treatment, and this series of steps Is repeated until the film thickness reaches 130 nm. A method for producing a bismuth-based layered perovskite thin film.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Next, the present invention will be described in detail.
In the present invention, first, as the Sr—Bi—Ta triple alkoxide precursor solution used (Sr [BiTa (OR) ₉ ] ₂ , R: an organic functional group containing C, H, O), for example, Sr [BiTa ( OC ₂ H ₄ OCH ₃ ) ₉ ] ₂ and Sr [BiTa (OC ₂ H ₅ ) ₉ ] ₂ are preferable examples. However, what is used by this invention is not restricted to these, The suitable alkoxide shown by general formula (OR) (R: organic functional group containing C, H, O) can be used. Moreover, as a solvent alcohol, what is necessary is just a thing which can melt | dissolve the said Sr-Bi-Ta triple alkoxide, For example, although 2-methoxyethanol and ethanol are illustrated as a suitable thing, it is not restricted to this. Any suitable alcohol can be used.
[0008]
In the present invention, a precursor solution is prepared by subjecting the prepared Sr—Bi—Ta triple alkoxide to hydrolysis polycondensation reaction using water. In this case, water having a molar ratio of 1/18 to 1/6 is added. It is preferable to use it. Next, a thin film of the Sr—Bi—Ta triple alkoxide is formed on the substrate surface using this precursor solution. In this case, as a coating method, for example, dip coating, spin coating, printing method and the like are exemplified as suitable ones. However, the coating method is not limited thereto, and an appropriate method may be used as long as it is a method having the same effect. it can. The substrate may be any material that can be coated with Pt as a surface electrode. Examples thereof include metals, oxide single crystals, ceramics, and the like, but any suitable substrate may be used regardless of the material and shape. Can do.
[0009]
Next, the manufacturing process will be described. That is, after the Sr—Bi—Ta triple alkoxide precursor solution prepared as described above is coated on a substrate with a Pt electrode, a drying process is performed, and this temperature is preferably such that only the solvent used can be vaporized. For example, when 2-methoxyethanol is used as a solvent, about 150 ° C. is preferable. Subsequently, UV irradiation is performed after drying. As the light source to be used, an ultra-high pressure mercury lamp or a low-pressure mercury lamp is exemplified as a suitable light source, but any light source that emits ultraviolet light having a wavelength region of 350 nm to 450 nm or 250 nm to 300 nm may be used. Not limited. Further, the reaction time can be controlled by the irradiation energy density, and the reaction time can be shortened by using a light source having a high energy density. However, this does not apply to laser light sources. Subsequently, a calcination treatment is performed after the irradiation with ultraviolet rays. At this time, a temperature at which an organic substance existing in the thin film can be efficiently decomposed and vaporized is required. For example, Sr [BiTa (OC ₂ When H ₄ OCH ₃ ) ₉ ] ₂ is used, about 350 ° C. is preferable. Subsequently, after calcining, heat treatment is performed in an oxygen stream. In this process, a rapid temperature increase of 100 ° C./second is indispensable in order to suppress side reactions, and a crystallization temperature of 650 ° C. is suitable. is there. The film thickness can also be adjusted by repeating the coating to the calcining operation and finally performing a rapid heat treatment once. However, in order to produce a thin film with better crystallinity, the coating can be crystallized. It is necessary to adjust by repeating a series of operations up to the conversion.
[0010]
As described above, the present invention can control the crystallinity, orientation, and surface smoothness of a bismuth-based layered perovskite thin film by simply irradiating the thin film before crystallization under various conditions. It is a revolutionary method.
[0011]
【Example】
Next, the present invention will be specifically described based on examples, but the present invention is not limited to the examples.
Example 1
(1) Method Sr—Bi—Ta triple alkoxide was synthesized according to the previous report (references [8, 9]), and after partial hydrolysis, this was spin-coated on a Si substrate with a Pt electrode. After drying this at 150 ° C., using a 250 W ultra high pressure mercury lamp (multilightUIV-270, Ushi Co. Ltd., Tokyo, Japan, main wavelengths: 365 nm, 405 nm, 436 nm, energy density of 70 mW / cm ² or less) Below, ultraviolet irradiation was performed for a predetermined time. The irradiation distance was about 15 cm. Then, it was calcined at 350 ° C. in air, and further subjected to rapid heat treatment (100 ° C./s) up to 650 ° C. in an oxygen stream, and held for 10 minutes. This series of operations was repeated five times until the film thickness reached 130 nm, and the crystal structure was analyzed by X-ray diffraction (XRD, RINT2100V / PC, Rigaku Co. Ltd., Tokyo, Japan). Using CuKα rays, the acceleration voltage and current were 40 kV and 40 mA, respectively. The orientation of SBT was compared by the intensity of the (001) diffraction peak, and the crystallinity was evaluated by measuring a rocking curve at the (008) diffraction peak. Furthermore, the surface state was observed and evaluated with an atomic force microscope (AFM, Nanoscope III, Digital Instruments, Inc. CA, USA).
[0012]
(2) Results FIG. 1 shows an XRD diffractogram of the SBT thin film produced by irradiating the thin film before calcination with ultraviolet rays at room temperature using an ultra-high pressure mercury lamp. It was found that the thin film prepared without being irradiated with ultraviolet rays was an SBT single phase and exhibited C-axis orientation on a substrate with a Pt electrode. And it became clear that the crystallinity of this C-axis oriented thin film is improved by irradiating with ultraviolet rays with an ultra-high pressure mercury lamp at room temperature. In addition, this tendency became more prominent as the irradiation time became longer. Furthermore, a θ scan was performed to quantify the degree of crystallinity. As a result, the half width of the (008) diffraction peak of the SBT thin film prepared without ultraviolet irradiation was 12.4 °. The thickness of the thin film prepared by irradiating with a high pressure mercury lamp for 1 hour was 9.0 °. From this result, it was confirmed that the crystallinity was improved in the latter case. The SBT thin film shows C-axis orientation because the lattice matching between the (111) plane of the Pt electrode and the (001) plane of the SBT is good, but the C-axis orientation of this SBT thin film under the above conditions. This is considered to be because the interaction between the Pt electrode and the SBT thin film is enhanced by ultraviolet irradiation. Furthermore, as shown in FIG. 2, from the results of AFM observation, when irradiated with ultraviolet light under this condition, the Ra value, which is an index of surface roughness, changes from 10.6 nm to 7.8 nm, which is smoother. It became clear that it became a surface.
[0013]
Example 2
(1) Method Sr—Bi—Ta triple alkoxide was synthesized according to the previous report (references [8, 9]), and after partial hydrolysis, this was spin-coated on a Si substrate with a Pt electrode. This was dried at 150 ° C., and then irradiated with ultraviolet rays for a predetermined time at room temperature using a 15 W low-pressure mercury lamp (GL-15, Toshiba Co. Ltd., Tokyo, Japan, main wavelength: 254 nm, energy density 1 mW / cm ² ). Went. The irradiation distance was about 15 cm. Then, it was calcined at 350 ° C. in air, and further subjected to rapid heat treatment (100 ° C./s) up to 650 ° C. in an oxygen stream, and held for 10 minutes. This series of operations was repeated five times until the film thickness reached 130 nm, and the crystal structure was analyzed by X-ray diffraction (XRD, RINT2100V / PC, Rigaku Co. Ltd., Tokyo, Japan). Using CuKα rays, the acceleration voltage and current were 40 kV and 40 mA, respectively. Further, the orientation of SBT was evaluated by the intensity of (00l) and (115) diffraction peaks. Furthermore, the surface state was observed and evaluated with an atomic force microscope (AFM, Nanoscope III, Digital Instruments, Inc. CA, USA).
[0014]
(2) Results FIG. 3 shows an XRD diffractogram when light irradiation is performed using a low-pressure mercury lamp at room temperature. Under these conditions, the results are different from the results shown in FIG. 1, and it has been clarified that the C-axis orientation is broken and the film has a random crystal orientation with an increased (115) diffraction intensity. And it became clear that this crystallinity improved with irradiation time. Since the (115) plane is a cleaved surface of SBT, it was considered that the SBT itself was stabilized in terms of energy when irradiated with ultraviolet light from a low-pressure mercury lamp at room temperature. Furthermore, as shown in FIG. 4, from the result of AFM observation, when irradiated with ultraviolet light under this condition, the Ra value changes from 10.6 nm to 8.4 nm, and the surface becomes slightly smoother. It became clear.
[0015]
Example 3
(1) Method Sr—Bi—Ta triple alkoxide was synthesized according to the previous report (references [8, 9]), and after partial hydrolysis, this was spin-coated on a Si substrate with a Pt electrode. After drying at 150 ° C., a 250 W ultra high pressure mercury lamp (multilightUIV-270, Ushi Co. Ltd., Tokyo, Japan, main wavelengths: 365 nm, 405 nm, 436 nm, energy density of 70 mW / cm 2 or less), or a 15 W low pressure mercury lamp (GL-15, Toshiba Co. Ltd., Tokyo, Japan, main wavelength: 254 nm, energy density 1 mW / cm 2), UV irradiation was performed for a predetermined time in a temperature atmosphere of 150 ° C. The irradiation distance was about 15 cm.
Then, it was calcined at 350 ° C. in air, and further subjected to rapid heat treatment (100 ° C./s) up to 650 ° C. in an oxygen stream, and held for 10 minutes. This series of operations was repeated five times until the film thickness reached 130 nm, and the crystal structure was analyzed by X-ray diffraction (XRD, RINT2100V / PC, Rigaku Co. Ltd., Tokyo, Japan). Using CuKα rays, the acceleration voltage and current were 40 kV and 40 mA, respectively. Further, the orientation of SBT was compared by the intensity of (001) and (115) diffraction peaks, and the crystallinity was evaluated by measuring a rocking curve at (115) diffraction peaks. Furthermore, the surface state was observed and evaluated with an atomic force microscope (AFM, Nanoscope III, Digital Instruments, Inc. CA, USA).
[0016]
(2) Results FIG. 5 shows an XRD diffractogram when ultraviolet irradiation is performed using an ultrahigh pressure mercury lamp while heating at 150 ° C. Under this condition, the same effect as when using a low-pressure mercury lamp at room temperature was observed. That is, it was revealed that the C-axis orientation was lost with the irradiation time, and the film had a random crystal orientation with an increased (115) diffraction intensity. This film showed higher crystallinity than when a low-pressure mercury lamp was used. In order to compare the crystallinity of a film produced using a low-pressure mercury lamp at room temperature and a film produced by light irradiation with an ultra-high pressure mercury lamp while heating at 150 ° C., the rocking curves at the (115) diffraction peak of both When the former was measured, the half width was 10.2 ° in the former case and 8.3 ° in the latter case. Further, the film was randomly oriented when it was irradiated with ultraviolet rays using a low-pressure mercury lamp while being heated at 150 ° C. However, the film in this case has a lower crystallinity when a low-pressure mercury lamp is used at room temperature than when an ultrahigh-pressure mercury lamp is used while heating at 150 ° C., and the half width at the (115) diffraction peak is 14 It was 5 °. Furthermore, as shown in FIG. 6, from the results of AFM observation, when irradiated with ultraviolet light under these conditions, the Ra value changed from 10.6 nm to 3.9 nm, and the film had a considerably improved surface smoothness. It became clear that
From the above results, in order to produce an SBT thin film with improved smoothness and good crystallinity (115) direction, it is more effective to use an ultra-high pressure mercury lamp while heating at 150 ° C. It became clear. That is, the existence of wavelength dependence in the photochemical reaction of the SBT thin film before crystallization on such a Si substrate with a Pt electrode was clarified.
[0017]
From the above results, the crystallinity, orientation, and surface smoothness can be improved by irradiating the SBT thin film before crystallization on the Si substrate with a Pt electrode under three types of conditions. It became clear. The photochemical reaction using an ultra-high pressure mercury lamp at room temperature was effective for enhancing the interaction with the Pt electrode and improving the crystallinity of the film. On the other hand, when using an ultra-high pressure mercury lamp at 150 ° C. and using a low-pressure mercury lamp at room temperature, it becomes clear that the orientation of the SBT thin film can be changed in the (115) direction. It became clear that the effect was larger. Since the (115) plane is a cleavage plane of SBT, it was considered that the surface itself was more energetically stabilized under these conditions.
[0018]
References
[1] HN Al-Shareef, D. Dimos, TJ Boyle, WL Warren and BA Tuttle, Appl. Phys. Lett., 68 [5] 690 (1996).
[2] D. Dimos, HN Al-Shareef, WL Warren and BA Tuttle, J. Appl. Phys., 80 [3] 1682 (1996).
[3] T. Noguchi, T. Hase and Y. Miyasaka, Jpn. J. Appl. Phys., 35 [9B] 4900 (1996).
[4] Y. Ito, M. Ushikubo, S. Yokoyama, H. Matsunaga, T. Atsuki, T. Yonezawa and K. Ogi, Jpn. J. Appl. Phys., 35 [9B] 4925 (1996).
[5] T. Hayashi, H. Takahashi and T. Hara, Jpn. J. Appl. Phys., 35 [9B] 4952 (1996).
[6] H. Watanabe, T. Mihara, H. Yoshiori and CA Paz de Araujo, Jpn. J. Appl. Phys., 34 [9B] 5240 (1995).
[7] T. Li, Y. Zhu, SB Desu, CH Peng and M. Nagata, Appl. Phys. Lett., 68 [5] 616 (1996).
[8] K. Kato, C. Zheng, JM Finder, SK Dey and Y. Torii, J. Am. Ceram. Soc., 81 1869 (1996).
[9] Kato Kazumi, Sundip Kumar Day, Patent No. 2967189
[10] K. Kato, C. Zheng, SK Dey and Y. Torii, Integr. Ferroelectr., 18225 (1997).
[11] GD Hu, IH Wilson, JB Xu, CP Li, and SP Wong, Appl. Phys. Lett., 76 [13] 1758 (2000).
[0019]
【The invention's effect】
As described above in detail, the present invention is a method in which a partially hydrolyzed Sr—Bi—Ta triple alkoxide precursor solution is coated on a Si substrate with a Pt electrode, dried, and then an ultrahigh pressure mercury lamp or It relates to a method for efficiently controlling the crystallinity, orientation and surface smoothness of the SBT thin film by irradiating with ultraviolet rays using a low-pressure mercury lamp, and 1) the crystallinity and surface smoothness are improved by the present invention. A C-axis oriented bismuth-based layered perovskite SBT thin film can be efficiently produced, and 2) a bismuth-based layered perovskite SBT thin film with good crystallinity and surface smoothness mainly oriented in the (115) direction can be efficiently produced. Functional integration material for low temperature and efficient process of bismuth-based layered perovskite thin film with excellent ferroelectric properties Can contribute greatly to the development of, particular effects etc. are obtained.
[Brief description of the drawings]
FIG. 1 shows an XRD diffraction pattern of an SBT thin film formed on a silicon substrate with a Pt electrode by irradiation with ultraviolet light from an ultrahigh pressure mercury lamp at room temperature. Irradiation time (a): 0 minutes, (b): 30 minutes, (c): 60 minutes [Fig. 2] AFM of SBT thin film prepared on a silicon substrate with a Pt electrode by irradiation with ultraviolet light from an ultra-high pressure mercury lamp at room temperature An observation image is shown. Irradiation time (a): 0 minutes, (b): 60 minutes FIG. 3 shows an XRD diffraction pattern of an SBT thin film formed on a silicon substrate with a Pt electrode by irradiation with ultraviolet light from a low-pressure mercury lamp at room temperature. Irradiation time (a): 0 minutes, (b): 30 minutes, (c): 60 minutes [FIG. 4] AFM observation of an SBT thin film prepared on a silicon substrate with a Pt electrode by irradiation with ultraviolet light from a low-pressure mercury lamp at room temperature. Show the image. Irradiation time (a): 0 minutes, (b): 60 minutes [Fig. 5] XRD diffraction pattern of an SBT thin film prepared on a silicon substrate with a Pt electrode by irradiating ultraviolet rays from an ultra-high pressure mercury lamp under a temperature condition of 150 ° C. Show. Irradiation time (a): 0 minutes, (b): 30 minutes, (c): 60 minutes [Fig. 6] Fabricated on a silicon substrate with a Pt electrode by irradiation with ultraviolet light from an ultra-high pressure mercury lamp at a temperature of 150 ° C. An AFM observation image of an SBT thin film is shown. Irradiation time (a): 0 minutes, (b): 60 minutes

Claims (8)

Crystals coated on a substrate with a Pt electrode using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (an organic functional group containing Sr [BiTa (OR) ₉ ] ₂ , R: C, H, O) as a precursor solution. A method for controlling crystallinity / orientation / surface smoothness of a bismuth-based layered perovskite SBT thin film, wherein the SrBi ₂ Ta ₂ O ₉ (SBT) thin film before irradiation is irradiated with ultraviolet rays. SrBi ₂ Ta ₂ O ₉ (SBT) thin film before crystallization coated with a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) on a substrate with a Pt electrode The method for controlling crystallinity, orientation, and surface smoothness of a bismuth-based layered perovskite SBT thin film according to claim 1, wherein ultraviolet irradiation is performed at room temperature using an ultrahigh pressure mercury lamp. Using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution, an SBT thin film coated on a substrate with a Pt electrode was crystallized at room temperature using a low-pressure mercury lamp. 2. The method for controlling the crystallinity and orientation of a bismuth-based layered perovskite SBT thin film according to claim 1, wherein ultraviolet irradiation is performed underneath. Using a partially hydrolyzed Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ) as a precursor solution, an SBT thin film coated on a substrate with a Pt electrode was crystallized at room temperature using a low-pressure mercury lamp. 2. The method for controlling the surface smoothness of a bismuth-based layered perovskite SBT thin film according to claim 1, wherein ultraviolet irradiation is performed underneath. Using Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ), which has been partially hydrolyzed, as a precursor solution, an SBT thin film before crystallization coated on a substrate with a Pt electrode, using an ultrahigh pressure mercury lamp 2. The crystallinity / orientation control method for a bismuth-based layered perovskite SBT thin film according to claim 1, wherein ultraviolet irradiation is performed under a temperature condition of 150.degree. Using Sr—Bi—Ta triple alkoxide (Sr [BiTa (OR) ₉ ] ₂ ), which has been partially hydrolyzed, as a precursor solution, an SBT thin film before crystallization coated on a substrate with a Pt electrode, using an ultrahigh pressure mercury lamp 2. The method of controlling surface smoothness of a bismuth-based layered perovskite SBT thin film according to claim 1, wherein ultraviolet irradiation is performed under a temperature condition of 150.degree. Using the partially hydrolyzed Sr-Bi-Ta triple alkoxide precursor solution according to any one of claims 1 to 6, by a coating method or a printing method such as dip coating or spin coating, a metal with a Pt electrode, oxidation A method for producing a bismuth-based layered perovskite thin film, comprising forming a thin film on the surface of a substrate such as an object single crystal or ceramics. A thin film before crystallization on a substrate with a Pt electrode produced by light irradiation according to any one of claims 1 to 6 is calcined and subjected to a rapid heating treatment, and the film thickness is changed to 130 nm. It repeats until it becomes, The manufacturing method of the bismuth type | system | group layered perovskite thin film characterized by the above-mentioned.

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