JP4237861B2 - Highly monocrystalline zinc oxide thin film and manufacturing method - Google Patents

Highly monocrystalline zinc oxide thin film and manufacturing method Download PDF

Info

Publication number
JP4237861B2
JP4237861B2 JP08823199A JP8823199A JP4237861B2 JP 4237861 B2 JP4237861 B2 JP 4237861B2 JP 08823199 A JP08823199 A JP 08823199A JP 8823199 A JP8823199 A JP 8823199A JP 4237861 B2 JP4237861 B2 JP 4237861B2
Authority
JP
Japan
Prior art keywords
thin film
zinc oxide
ysz
film
substrate
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
JP08823199A
Other languages
Japanese (ja)
Other versions
JP2000281495A (en
Inventor
裕道 太田
博司 川副
政寛 折田
秀雄 細野
Original Assignee
Hoya株式会社
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 Hoya株式会社 filed Critical Hoya株式会社
Priority to JP08823199A priority Critical patent/JP4237861B2/en
Publication of JP2000281495A publication Critical patent/JP2000281495A/en
Application granted granted Critical
Publication of JP4237861B2 publication Critical patent/JP4237861B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an article having a highly monocrystalline zinc oxide thin film and a method for producing the same.
[0002]
The zinc oxide thin film of the article of the present invention not only has high single crystallinity, but also can control the concentration of conductive carriers (electrons) by carrier doping by the valence control method, and also has transparency over the entire visible range. Since it is excellent, it is particularly useful as an organic EL substrate, a color filter substrate for a display that requires light transmission, and an electrode for a solar cell. Furthermore, it is useful for improving the performance and extending the life of elements by applying it to the manufacture of ultraviolet to blue laser devices, SAW devices, and thin film varistors. In addition, the manufacturing method of the present invention is a method capable of manufacturing a high-quality single crystal ZnO thin film even at a higher film forming rate than when glass, sapphire (0001), or the like is used as a substrate.
[0003]
[Prior art]
A transparent electrode material that is transparent in the visible light region and has electrical conductivity is used as a transparent electrode for various panel displays such as liquid crystal displays and EL displays, and solar cells.
[0004]
As the transparent electrode material, a metal oxide semiconductor is generally used, and various proposals have been made including indium oxide (ITO) doped with tin. Among them, ITO has been often used as a transparent electrode for panel type displays. However, in recent years, panel-type displays have been increased in size and definition, and the resistivity of ITO is insufficient. That is, in a large display, since the distance between the ends of the transparent electrode is increased, the resistance between the end points is increased. In addition, high definition increases the resistance value between the end points in order to narrow the width of the electrode. In general, the thickness of the electrode may be increased in order to reduce the resistance value between the end points. However, in the case of an ITO electrode, when the thickness is increased, it is colored yellow and the transparency is impaired. This is because ITO has a phenomenon in which light having a wavelength of 450 nm or less is absorbed by indirect transition. This is hardly an issue when the electrode thickness is small. However, as the thickness of the electrode increases, it is clearly recognized by the human eye. For this reason, conventionally, ITO that has been practically used as a transparent electrode material has not been able to obtain a large-sized or high-definition transparent electrode that satisfies both transparency and electrical conductivity.
For these reasons, it has been a challenge to develop materials that are transparent and have high conductivity even in the short wavelength region of 450 nm or less in the visible region.
[0005]
A candidate for a transparent electrode material replacing ITO is a zinc oxide (hereinafter ZnO) thin film. ZnO is known as an II-VI group n-type semiconductor with an energy difference (band gap) from the valence band to the forbidden band of about 3.3 eV. ZnO thin films produced by thin film methods (CVD, sputtering, MBE, PLD, etc.) are transparent from the visible to the near infrared region, and are known to be thin films oriented in the c-axis regardless of the substrate type. ing. ZnO, which has high single crystallinity, has a large conductivity in the c-plane and is known to exhibit a Hall mobility larger than that of indium oxide, and research on application as a transparent conductive film has been advanced. In order to apply ZnO as a transparent conductive film, trivalent or higher metal ions such as Al, Ga, and In are substituted at the Zn position of ZnO by utilizing the fact that ZnO is an oxygen-deficient n-type semiconductor ( By controlling the valence, it becomes possible by introducing electrons as carriers into the ZnO crystal.
[0006]
High resolution X-ray diffraction is usually used for evaluation of single crystallinity. The orientation of the specific surface is examined by θ-2θ scan, and the inclination of the orientation with respect to the substrate surface is examined by a θ-rocking curve (ω-scan). Usually, it is said that single crystallinity is high when the half width (FWHM) of the θ-rocking curve (ω-scan) is 0.3 deg. Or less. The orientation in the in-plane direction of the substrate is evaluated by measuring the pole figure and examining the mosaic property of the crystal.
[0007]
Typical methods for producing a ZnO thin film include CVD, spraying, vacuum deposition, ion plating, MBE, sputtering, sol-gel, and spray pyrolysis. Further, examples of the CVD method include a thermal CVD method, a plasma CVD method, an MOCVD method, and a photo CVD method.
[0008]
Chemical methods such as CVD and spraying have simpler equipment than physical methods such as vacuum deposition and sputtering, and are suitable for manufacturing large substrates. Furthermore, when performing a drying or firing process for promoting the reaction or stabilizing the characteristics, a heat treatment at 300 to 500 ° C. is required, which is suitable for direct production on a glass substrate.
[0009]
The physical method allows the substrate temperature during film formation to be as low as 150 to 300 ° C. Therefore, not only when manufacturing a thin film directly on a glass substrate, but also when manufacturing on various underlayers Is also suitable. Among these, the sputtering method is excellent in that it has high productivity and can form a film even on a large area substrate.
[0010]
In recent years, with the widespread use of laser ablation (PLD) equipment used for atomic layer growth such as high-temperature superconductors, it has become possible to easily produce highly crystalline ZnO thin films. : 10000Scm-1ZnO thin film (Al-doped) equivalent to that of Al.) Can be fabricated on a glass substrate by the PLD method (for example, A. Suzuki, T. Matsushita, N. Wada, Y. Sakamoto and M. Okuda, JJAP, 35 , L56-L59 (1996).).
[0011]
It is said that the scattering factor of electrically conductive carriers in ZnO thin films is mainly grain boundaries, so the single-crystal Hall mobility without grain boundaries is 200 cm.2Also reaches / Vs. Conventionally, a method of forming a film on a sapphire (0001) substrate by a MOCVD method or a PLD method is generally used as a method for producing a single crystal ZnO thin film. In addition, it has been reported that a single crystal ZnO thin film formed on a sapphire substrate by the above method oscillates at an ultraviolet laser temperature at room temperature. When a ZnO thin film is deposited on a sapphire (0001) substrate, ZnO also grows in the (0001) direction. In this case, since the lattice irregularity of sapphire (0001) and ZnO (0001) is as large as about 18%, it is known that epitaxial growth occurs in a higher-order growth mode called higher order epitaxy rather than one-to-one epitaxial growth. .
[0012]
[Problems to be solved by the invention]
However, the prior art has the following problems.
When sapphire (0001) is used as a ZnO thin film deposition substrate, lattice disorder at the substrate-film interface is likely to occur due to the large lattice irregularity between ZnO and sapphire, thereby improving single crystallinity. However, there is a manufacturing problem that the film forming speed needs to be extremely slow and the film forming speed cannot be increased. GaN (0001) / Si (111) and CaF as semiconductor materials with small lattice mismatch with ZnO2(111) / Si (111) has already been reported, but since these substrates are all formed on Si, they are not suitable for mass production, and since Si is not transparent, There was a problem that it could not be applied.
[0013]
Therefore, an object of the present invention is to provide an article having a zinc oxide thin film having excellent visible light transmittance at 450 to 800 nm including a substrate and high single crystallinity.
A further object of the present invention is to provide a method capable of producing an article having a zinc oxide thin film having high single crystallinity at a higher speed than the conventional method, using a substrate excellent in visible light transmittance at 450 to 800 nm.
[0014]
[Means for Solving the Problems]
  The present invention relates to YSZ (yttria stabilized zirconiA) Thin filmA high monocrystalline zinc oxide thin film is provided on at least a part of the YSZ thin film of the substrate having at least a part of at least one surface thereof. Furthermore, the present inventionIs YSZ (yttria stabilized zirconiA) ThinForming a highly monocrystalline zinc oxide thin film on at least a part of the YSZ thin film of a substrate having a film on at least a part of at least one surface by a thin film method using a zinc oxide sintered body as a target. The present invention relates to a method for producing an article having a highly monocrystalline zinc oxide thin film.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
  FirstIs an article having a highly monocrystalline zinc oxide thin film on at least a part of at least one surface of a yttria-stabilized zirconia (hereinafter abbreviated as YSZ) substrate. Second aspect (The present invention (article))Is an article having a highly monocrystalline zinc oxide thin film on at least a part of the YSZ thin film of the substrate having the YSZ thin film on at least a part of at least one surface.
[0016]
substrate
As a result of searching for a material that is transparent in the visible to near infrared region and stable in the atmosphere, the present inventors have found that YSZ (yttria stabilized zirconia) is a transparent material from the visible to the near infrared region. YSZ single crystals are suitable for use as single crystal ZnO thin film deposition substrates because of their low defect density and high strength because they are produced by a single phase growth method using a liquid phase method. The YSZ thin film can be formed on a substrate of glass, single crystal, plastic, or the like by sputtering or laser ablation.
[0017]
Pure zirconium oxide (zirconia) has a monoclinic crystal system at room temperature, and cubic crystals with higher symmetry become stable at high temperatures. The crystal structure (cubic) of zirconium oxide at high temperature is fluorite (CaF2) Type, and by doping with yttrium oxide (yttria) or calcium oxide (calcia), the cubic crystal becomes stable at room temperature. Therefore, yttrium oxide (yttria) is added and fluorite (CaF stable at room temperature)2) Type yttria stabilized zirconia (YSZ) is used.
[0018]
In particular, as a substrate and a thin film in the present invention, YSZ (yttria stabilized zirconia) is preferably a (111) plane because it has better lattice matching with ZnO than sapphire (0001). However, in the case of the SAW device, the high single crystal zinc oxide thin film can be oriented to (110) by using YSZ (110). The yttria content in yttria-stabilized zirconia (YSZ) is suitably in the range of more than 0 and not more than 20 wt%. YSZ is an element other than yttrium (for example, calcium, magnesium (any element can stabilize zirconia into cubic crystals)), etc., so that the substrate and the thin film are not colored (for example, visible at 450 to 800 nm). For example, the light transmittance may be included in the range of 80% or more. In particular, when the article of the present invention is used as an electrode, it is appropriate to use a highly transparent substrate in the visible light region.
[0019]
The YSZ substrate (YSZ bulk) used in the first embodiment and the YSZ thin film used in the second embodiment are both optically polished and preferably have an inclination angle of 10% or less. In addition, using a YSZ substrate flattened in the atomic order by techniques such as thermal etching or chemical etching at 1000 to 1500 ° C. in the atmosphere increases the single crystallinity of the zinc oxide thin film provided on it and increases the crystal grain size. There is an advantage that can be done.
[0020]
  As a substrate material for forming YSZ thin filmsUse sapphire. 450Those having excellent visible light transmittance at ˜800 nm (specifically, those having an average visible light transmittance at 450 to 800 nm of 95% or more) are preferred. YSZ thin film is on this substrateShapeCan be made. However, it is preferable to select a method and conditions that can form the YSZ (111) plane. Further, the film thickness of the YSZ thin film is not particularly limited, but for example, it is appropriate to set it in the range of 10 to 200 nm. The use of a sapphire substrate as the substrate on which the YSZ thin film is formed is preferable in the following points. That is, using a YSZ thin film having high single crystallinity formed on a sapphire substrate by laser ablation is effective in increasing the single crystallinity of the zinc oxide thin film and increasing the crystal grain size.
[0021]
High monocrystalline zinc oxide thin film
In the present invention, the high single crystal zinc oxide thin film means a zinc oxide thin film having high single crystallinity. The single crystallinity of the thin film is evaluated by using high-resolution X-ray diffraction, examining the orientation of a specific surface by θ-2θ scanning, and further examining the inclination of the orientation relative to the substrate surface by a θ-rocking curve (ω-scan). Can be done. In the present invention, “high single crystallinity” means that the half width (FWHM) of the θ-rocking curve (ω-scan) is 0.3 deg. Or less, preferably 0.2 deg. Or less, more preferably 0.1 deg. Or less. . The higher the single crystallinity, the higher the visible light transmittance and the higher the Hall mobility.
In the case of the article according to the first aspect, the high single crystal zinc oxide thin film is provided on at least a part of at least one surface of the YSZ substrate. A high monocrystalline zinc oxide thin film may be provided on part or all of one surface. In the case of the article of the second aspect, the high single crystal zinc oxide thin film is provided on at least a part of the YSZ thin film of the substrate having the YSZ thin film on at least a part of at least one surface. Specifically, the article according to the aspect is one in which a high monocrystalline zinc oxide thin film is provided on a part or all of the YSZ thin film of a substrate having the YSZ thin film on a part or all of one surface. be able to.
Further, the film thickness of the high monocrystalline zinc oxide thin film is not particularly limited, but considering that it is appropriate that the transmittance in the visible light region is 80% or more, for example, 200 nm to 3 μm It can be a range.
[0022]
The highly monocrystalline zinc oxide thin film of the present invention may further contain at least one element selected from the group consisting of Al, Ga, In, Y, Si, Ti, Zr, Hf, Ge, B, and F. it can. These elements can increase the conductive carrier (electron) concentration of the high single crystal zinc oxide thin film, or can impart physical properties such as high conductivity and light absorption (plasma absorption) in the infrared region. The content of these elements can be appropriately determined in consideration of the amount of carrier electrons required for the thin film, the transmittance in the visible light region, and the like, and is, for example, in the range of 0 to 10% by weight.
High single crystal zinc oxide thin film has 1 × 10 carrier electronsTen/cmThree~ 1 × 10twenty two/cmThreeIt is appropriate from the viewpoint of obtaining good conductivity. From the viewpoint of higher conductivity, the amount of carrier electrons is 1 × 1017/cmThree~ 1 × 10twenty two/cmThreeIt is preferable that it is the range of these. The conductive carrier (electron) concentration can be controlled by carrier doping by the valence control method as described above.
[0023]
The high single crystal zinc oxide thin film of the present invention can further contain at least one element selected from the group consisting of Li, Na and K. These elements can reduce the conductive carrier (electron) concentration of the high single crystal zinc oxide thin film and impart physical properties such as piezoelectricity. The content of these elements can be appropriately determined in consideration of the solid solution range and the like, and is, for example, in the range of 0 to 10% by weight.
[0024]
Since the article having the highly monocrystalline zinc oxide thin film of the present invention is excellent in transparency in the entire visible region, it is an organic EL substrate, a color filter substrate for a display that requires light transmission, and an electrode for a solar cell. It is useful as such. Furthermore, it is useful for improving the performance and extending the life of elements by applying it to the manufacture of ultraviolet to blue laser devices, SAW devices, and thin film varistors.
The present invention includes a surface acoustic wave (SAW) filter characterized in that an interdigital electrode is formed on a high single crystal zinc oxide thin film of an article having the high single crystal zinc oxide thin film of the present invention. “Interdigital electrode” refers to an input / output electrode of a SAW device. When an electric signal is applied to the interdigital electrode, periodic mechanical distortion occurs between the electrodes due to the piezoelectric effect, and surface waves are excited. The interdigital electrode can be formed by a method such as vapor deposition or sputtering.
[0025]
Production method
The method for producing an article having a highly monocrystalline zinc oxide thin film according to the present invention includes the YSZ thin film on a substrate having at least a part of at least one surface of the YSZ substrate or at least a part of at least one surface of the YSZ substrate Forming a highly monocrystalline zinc oxide thin film on at least a part of the film by a thin film method using a zinc oxide sintered body as a target. By this method, an article having the highly crystalline zinc oxide thin film of the present invention can be produced.
The substrate having the YSZ substrate and the YSZ thin film used in the production method of the present invention can be the same as described in the article of the present invention.
In the production method of the present invention, a highly monocrystalline zinc oxide thin film is formed by a thin film method using a zinc oxide sintered body as a target. The zinc oxide sintered body can be used as it is obtained by a conventional method.For example, after zinc oxide powder having an average particle diameter of 1 μm is formed into a disk shape by CIP molding at a pressure of 196 Mpa, It can be sintered for 6 hours. In the production method of the present invention, the single crystallinity of the formed zinc oxide thin film hardly changes depending on the density of the target. However, when the laser ablation method is used as the thin film method, the zinc oxide sintered body used as the target has a relative density of 60% or more, preferably 90% or more in consideration of damage to the target due to laser pulse irradiation. It is.
[0026]
Further, the zinc oxide sintered body can further contain at least one element selected from the group consisting of Al, Ga, In, Y, Si, Ti, Zr, Hf, Ge, B, and F. These elements can be added to the high single crystal zinc oxide thin film by using a simple target. In addition, the zinc oxide sintered body can further contain at least one element selected from the group consisting of Li, Na and K. Similarly to the above, by using such a target, high single crystallinity can be obtained. These elements can be added to the zinc oxide thin film.
As a target containing these elements, for example, zinc oxide having a predetermined amount of oxides of these elements mixed, molded, and sintered can be used.
[0027]
Examples of the thin film method include a CVD method, a spray method, a vacuum deposition method, an ion plating method, an MBE method, a sputtering method, a sol-gel method, and a spray pyrolysis method. Further, examples of the CVD method include a thermal CVD method, a plasma CVD method, an MOCVD method, and a photo CVD method. However, composition deviation hardly occurs, and high oxygen pressure (for example, 100 Pa) to low oxygen pressure (10-FiveFrom the viewpoint of being able to form a film up to Pa) and having few impurities, it is preferable to use a laser ablation method as a thin film method.
[0028]
Laser ablation method
The laser ablation method is a method of synthesizing a thin film through an ablation process using laser light, and has recently been attracting attention as a method replacing the sputtering method. Ablation is a phenomenon in which components suddenly generate heat and photochemical reaction on the surface of an object irradiated with strong light energy, causing components to vaporize explosively. Features of film formation by laser ablation
(1) Easy synthesis of high melting point thin films
(2) Capable of film formation in a clean atmosphere that does not require a raw material heating source
(3) Wide variation in gas partial pressure in the deposition chamber
(4) Small composition deviation between target and film
(5) The film composition can be controlled digitally
Etc.
[0029]
The inventors made a prototype zinc oxide thin film on a YSZ substrate (particularly a YSZ (111) substrate) by laser ablation. As a result, the half-value width of the X-ray diffraction θ rocking curve, which is one of the means for evaluating the single crystallinity of the zinc oxide thin film, is very narrow, 0.1 deg. A zinc oxide thin film having higher single crystallinity than the prototype zinc oxide thin film can be produced. Furthermore, thin films produced by laser ablation on YSZ substrates (especially YSZ (111) substrates) have high Hall mobility due to their high single crystallinity, and visible light transmittance at 450 to 800 nm including the substrate is also high. It is expensive.
[0030]
Due to the difference in the lattice matching between the substrate and the ZnO (0001) surface, even when the YSZ substrate (especially YSZ (111) substrate) is used, the deposition rate is faster than when the sapphire (0001) surface is used. It is considered that a ZnO thin film with high single crystallinity can be produced. Further, the laser ablation method vaporizes a limited surface instantly and decomposes it to an atomic state, which is considered preferable for the production of a thin film having high single crystallinity.
[0031]
Laser ablation oxygen atmosphere
In the production method of the present invention, it is appropriate from the viewpoint that a highly monocrystalline zinc oxide thin film can be formed in an oxygen atmosphere by laser ablation in an oxygen atmosphere because a thin film excellent in crystallinity and transparency can be formed. . The oxygen partial pressure in the atmosphere is, for example, 1 × 10-6In the range of ~ 100Pa, preferably 1x10-3It is suitable to be in the range of ˜1 Pa.
[0032]
Laser ablation irradiation energy
The laser used in the laser ablation method of the production method of the present invention can be any wavelength from the ultraviolet region to the infrared region, that is, 0.19 to 11 mm, preferably 0.19 to 0.3 mm, and can be either continuous oscillation or pulse oscillation. Can be adopted. The laser intensity during laser irradiation is 0.0001 to 1000 J / cm2/ pulse, preferably 0.1-10J / cm2/ pulse. The substrate temperature is suitably 0 to 1000 ° C., desirably 25 to 800 ° C.
[0033]
【Example】
EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples, and can be implemented with appropriate modifications.
[0034]
  Reference example 1
  ZnO powder (purity 99.99%, manufactured by High Purity Chemical Laboratory Co., Ltd.) was formed into a disk shape with a diameter of 25 mm by uniaxial pressing, and sintered in the atmosphere at 1100 ° C. for 6 hours to obtain a zinc oxide sintered body . The surface of the obtained sintered body was polished using a # 800 diamond polishing plate to obtain a smooth surface as a laser ablation target.
[0035]
A laser ablation target was mounted on a target holder (manufactured by Inconel) and a YSZ (111) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (10Hz, 1J / cm under these conditions2/ pulse) for 30 minutes to form a zinc oxide thin film.
When the film thickness of the obtained zinc oxide thin film was measured with a stylus type step thickness meter, it was about 40 nm, and it was found that the film formation rate was about 0.2 angstrom / second. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. In addition, the XRD θ rocking curve was measured and the single crystallinity of the thin film was evaluated. The half-value width was about 0.1 deg., Indicating that the ZnO thin film had extremely high single crystallinity. As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 52 cm.2/ Vs, carrier concentration 0.89 × 1018cm-3The conductivity was 7.4 S / cm.
[0036]
Reference example 2
  referenceA laser ablation target was prepared by the method described in Example 1. A laser ablation target was mounted on a target holder (manufactured by Inconel) and a YSZ (111) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (10Hz, 0.5J / cm under these conditions2/ pulse) for 30 minutes to form a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured using a stylus type step thickness meter, it was found to be about 30 nm, indicating that the film formation rate was about 0.17 angstrom / second. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. In addition, when the XRD θ rocking curve was measured and the single crystallinity of the thin film was evaluated, the half width was about 0.1 deg. Or less, and it was found that the ZnO thin film had extremely high single crystallinity. As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 75 cm.2/ Vs, carrier concentration 0.98 × 1018cm-3The conductivity was 11.8 S / cm.
[0037]
Reference example Three
  referenceA laser ablation target was prepared by the method described in Example 1. A laser ablation target was mounted on a target holder (manufactured by Inconel) and a YSZ (111) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (1Hz, 0.5J / cm2/ pulse) for 300 minutes to form a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured using a stylus type step thickness meter, it was found to be about 30 nm, indicating that the film formation rate was about 0.017 angstrom / second. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. In addition, when the XRD θ rocking curve was measured and the single crystallinity of the thin film was evaluated, the half width was about 0.1 deg. Or less, and it was found that the ZnO thin film had extremely high single crystallinity. As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 131 cm.2/ Vs, carrier concentration 0.83 × 1018cm-3And the conductivity was 28 S / cm.
[0038]
[Table 1]
[0039]
Reference example Four
  (Reduction in resistance by Al doping) ZnO powder (manufactured by High-Purity Chemical Laboratory, purity 99.99%) and Al2OThree(Purity of High Purity Chemical Laboratory Co., Ltd., purity 99.99%) Powder was weighed and mixed to a weight ratio of 98: 2, then formed into a disk shape with a diameter of 25 mm by uniaxial pressure molding, and 1500 ° C in air And sintered for 6 hours to obtain a zinc oxide sintered body. The surface of the obtained sintered body was polished using a # 800 diamond polishing plate to obtain a smooth surface as a laser ablation target. A laser ablation target was mounted on a target holder (manufactured by Inconel) and a YSZ (111) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (10Hz, 3J / cm under these conditions2/ pulse) was formed for 15 minutes to produce a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured using a stylus type step film thickness meter, it was about 200 nm. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. Further, XRD θ rocking curve measurement was performed and the single crystallinity of the thin film was evaluated. The half width was about 0.05 deg., And it was found that the ZnO thin film had extremely high single crystallinity. As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 30 cm.2/ Vs, carrier concentration 1 × 10twenty onecm-3The conductivity was 4800 S / cm. The aluminum content is approximately 1x10 which is almost equal to the carrier concentration.twenty onecm-3Met.
[0040]
Reference example Five
  (High resistance by adding Li (for SAW devices)) ZnO powder containing 2atmic% of Li is formed into a disk shape with a diameter of 25mm by uniaxial pressure molding, and fired in the atmosphere at 1100 ° C for 6 hours to burn zinc oxide A ligature was obtained. The surface of the obtained sintered body was polished using a # 800 diamond polishing plate to obtain a smooth surface as a laser ablation target. A laser ablation target was mounted on a target holder (manufactured by Inconel) and a YSZ (111) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (10Hz, 3J / cm under these conditions2/ pulse) was formed for 15 minutes to produce a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured using a stylus type step film thickness meter, it was about 200 nm. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. Further, XRD θ rocking curve measurement was performed and the single crystallinity of the thin film was evaluated. The half width was about 0.03 deg., And it was found that the ZnO thin film had extremely high single crystallinity. The thin film had very high insulating properties, and the conductivity could not be measured.
[0041]
Example 6
(ZnO / YSZ thin film / sapphire)
  Reference exampleA zinc oxide target for laser ablation was prepared by the method described in 1. For YSZ target, Y2OThreeZrO containing 10wt%2The powder was formed into a disk shape having a diameter of 25 mm by uniaxial pressure forming and fired at 1600 ° C. for 2 hours in the air to obtain a zinc oxide sintered body. The surface of the obtained sintered body was polished using a # 800 diamond polishing plate to obtain a smooth surface as a laser ablation target. The laser ablation target was mounted on the target holder (manufactured by Inconel) and the sapphire (0001) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 800 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Under this condition, excimer laser pulse (1Hz, 1J / cm2/ pulse) to form a YSZ (111) thin film. Next, excimer laser pulse (10Hz, 1J / cm) on the zinc oxide target in the same way2/ pulse) was formed for 15 minutes to produce a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured using a stylus type step film thickness meter, it was about 150 nm. The thickness of the YSZ (111) thin film was about 50 nm. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. Further, XRD θ rocking curve measurement was performed and the single crystallinity of the thin film was evaluated. The half width was about 0.05 deg., And it was found that the ZnO thin film had extremely high single crystallinity. As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 120 cm.2/ Vs, carrier concentration 1 × 1018cm-3And the conductivity was 19 S / cm.
[0042]
Comparative example 1
  Reference exampleA laser ablation target was prepared by the method described in 1. The laser ablation target was mounted on the target holder (manufactured by Inconel) and the sapphire (0001) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. The sapphire (0001) substrate used was annealed at 1500 ° C. for 1 hour in the atmosphere to provide a flat surface on the atomic order. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (10Hz, 1J / cm under these conditions2/ pulse) for 30 minutes to form a zinc oxide thin film. When the thickness of the obtained zinc oxide thin film was measured using a stylus type step thickness meter, it was found to be about 40 nm, indicating that the film formation rate was about 0.2 angstrom / second. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. In addition, the XRD θ rocking curve was measured and the single crystallinity of the thin film was evaluated. The half-value width was about 0.5 deg. When using a YSZ substrate under the same film formation conditions (Reference exampleIt was found that the ZnO thin film had poor single crystallinity compared to 1). As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 11 cm.2/ Vs, carrier concentration 1.1 × 1018cm-3The electrical conductivity was 2.2 S / cm.
[0043]
Comparative example 2
  Reference exampleA laser ablation target was prepared by the method described in 1. The laser ablation target was mounted on the target holder (manufactured by Inconel) and the sapphire (0001) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. The sapphire (0001) substrate used was annealed at 1500 ° C. for 1 hour in the atmosphere to provide a flat surface on the atomic order. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (10Hz, 0.5J / cm under these conditions2/ pulse) for 30 minutes to form a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured using a stylus type step thickness meter, it was found to be about 30 nm, indicating that the film formation rate was about 0.17 angstrom / second. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. In addition, the XRD θ rocking curve was measured and the single crystallinity of the thin film was evaluated. The half-width was about 0.2 deg., So when using a YSZ substrate under the same film formation conditions (Reference exampleIt was found that the ZnO thin film had poor single crystallinity compared to 2). As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 15 cm.2/ Vs, carrier concentration 1.1 × 1018cm-3And the conductivity was 2.6 S / cm.
[0044]
Comparative example Three
  Reference exampleA laser ablation target was prepared by the method described in 1. The laser ablation target was mounted on the target holder (manufactured by Inconel) and the sapphire (0001) substrate was mounted on the substrate holder, introduced into the chamber, and then the inside of the apparatus was evacuated using a vacuum pump until a predetermined vacuum level was reached. The sapphire (0001) substrate used was annealed at 1500 ° C. for 1 hour in the atmosphere to provide a flat surface on the atomic order. Next, the target holder and the substrate holder were rotated in order to improve the uniformity of the film after film formation. The substrate temperature during film formation was 600 ° C. In order to improve the crystallinity of the film after film formation, oxygen gas (0.001 Pa) was introduced to increase the oxygen pressure. Excimer laser pulse (1Hz, 0.5J / cm2/ pulse) for 300 minutes to form a zinc oxide thin film. When the film thickness of the obtained zinc oxide thin film was measured with a stylus type step film thickness meter, it was about 30 nm, and it was found that the film formation rate was about 0.017 angstrom / second. Further, when the crystallinity was examined by XRD, a (002) plane diffraction peak was observed, confirming that the film was an alignment film. In addition, the XRD θ rocking curve was measured and the single crystallinity of the thin film was evaluated. The half-value width was 0.1 deg. When using a YSZ substrate under the same deposition conditions (Reference exampleIt was found that the ZnO thin film had poor single crystallinity compared with 3). As a result of measuring the conductivity of the thin film by the four-probe method and the Hall effect by the van der Pau method, the Hall mobility was 50 cm.2/ Vs, carrier concentration 0.99 × 1018cm-3The conductivity was 7.9 S / cm.
[0045]
[Table 2]
[0046]
【The invention's effect】
According to the present invention, by using a YSZ substrate or a YSZ thin film (especially a YSZ (111) substrate or thin film), a zinc oxide thin film having a single crystallinity equal to or higher than that of a sapphire (0001) substrate is used. It is possible to provide an article having Furthermore, this article is also excellent in visible light transmittance at 450 to 800 nm including the substrate. When the article having the highly monocrystalline zinc oxide thin film of the present invention is used, for example, as an electrode for a display or a solar cell that requires light transmission, a great effect can be expected in extending the life of the element. In addition, if it is used as an ultraviolet laser device, SAW device, or thin film varistor by taking advantage of its high single crystallinity, it can be expected to have a great effect on device performance.
In addition, according to the manufacturing method of the present invention, YSZ substrate or YSZ thin film (especially YSZ (111) substrate or thin film) compared to the case of using sapphire (0001) surface due to the difference in lattice matching of ZnO (0001) surface. By using this, a ZnO thin film having high single crystallinity can be produced even if the film formation rate is increased. That is, even if the film formation rate is increased, high single crystallinity can be maintained, and thus manufacturing is easy.According to the present invention, the Hall mobility is high and the visible light transmittance at 450 to 800 nm including the substrate is achieved. An article having an excellent zinc oxide thin film can be produced with high productivity.

Claims (9)

  1. Yttria-stabilized zirconia (hereinafter, you abbreviated as YSZ) FWHM of θ rocking curve X ray diffraction on at least a portion of the YSZ thin film of a sapphire substrate having on at least a portion of at least one surface of the thin film is 0.05 having a highly monocrystalline zinc oxide thin film that is less than or equal to deg.
    It yttria content of the YSZ film is 20wt% or less than 0, and (111) plane
    Articles sapphire substrate surface provided with the YSZ thin film and said <br/> it is (0001) plane.
  2. High single crystal zinc oxide thin film is Al, Ga, In, Y, Si, Ti, Zr, Hf, Ge, B, according to claim 1, and further comprising at least one element selected from the group consisting of F Goods.
  3. The article according to any one of claims 1 to 2 , wherein the amount of carrier electrons in the high single crystal zinc oxide thin film is in the range of 1 x 10 10 / cm 3 to 1 x 10 22 / cm 3 .
  4. The article according to claim 1, wherein the high monocrystalline zinc oxide thin film further comprises at least one element selected from the group consisting of Li, Na and K.
  5. A surface acoustic wave (SAW) filter, characterized in that an interdigital electrode is formed on the high single crystal zinc oxide thin film of the article according to any one of claims 1 to 4 .
  6. Yttria-stabilized zirconia (hereinafter, abbreviated as YSZ) over at least a portion of the YSZ thin film of a sapphire substrate having on at least a portion of at least one surface of the thin film, a thin film method using zinc oxide ceramics as a target To form a highly monocrystalline zinc oxide thin film with a half-width of the θ rocking curve of X- ray diffraction of 0.05deg. Or less
    It yttria content of the YSZ film is 20wt% or less than 0, and (111) plane
    A method for manufacturing an article having a highly monocrystalline zinc oxide thin film, wherein the surface of the sapphire substrate provided with the YSZ thin film is a (0001) plane .
  7. The manufacturing method according to claim 6 , wherein the zinc oxide sintered body further contains at least one element selected from the group consisting of Al, Ga, In, Y, Si, Ti, Zr, Hf, Ge, B, and F. .
  8. The manufacturing method according to claim 6 , wherein the zinc oxide sintered body further contains at least one element selected from the group consisting of Li, Na, and K.
  9. The manufacturing method according to any one of claims 6 to 8 , wherein the thin film method is a laser ablation method.
JP08823199A 1999-03-30 1999-03-30 Highly monocrystalline zinc oxide thin film and manufacturing method Expired - Lifetime JP4237861B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP08823199A JP4237861B2 (en) 1999-03-30 1999-03-30 Highly monocrystalline zinc oxide thin film and manufacturing method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP08823199A JP4237861B2 (en) 1999-03-30 1999-03-30 Highly monocrystalline zinc oxide thin film and manufacturing method

Publications (2)

Publication Number Publication Date
JP2000281495A JP2000281495A (en) 2000-10-10
JP4237861B2 true JP4237861B2 (en) 2009-03-11

Family

ID=13937103

Family Applications (1)

Application Number Title Priority Date Filing Date
JP08823199A Expired - Lifetime JP4237861B2 (en) 1999-03-30 1999-03-30 Highly monocrystalline zinc oxide thin film and manufacturing method

Country Status (1)

Country Link
JP (1) JP4237861B2 (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3398638B2 (en) * 2000-01-28 2003-04-21 裕道 太田 Light emitting diode, semiconductor laser and method for manufacturing the same
JP4164562B2 (en) 2002-09-11 2008-10-15 Hoya株式会社 Transparent thin film field effect transistor using homologous thin film as active layer
US20070193499A1 (en) * 2004-05-24 2007-08-23 Tsuguo Fukuda Zno single crystal as super high speed scintillator...
KR20100010929A (en) 2007-05-22 2010-02-02 고쿠리츠다이가쿠호진 나가오카기쥬츠가가쿠다이가쿠 Method and apparatus for production of metal oxide thin film
JP5408819B2 (en) 2008-01-29 2014-02-05 国立大学法人長岡技術科学大学 Deposition apparatus and deposition method
KR101258630B1 (en) 2008-11-21 2013-04-26 고쿠리츠다이가쿠호진 나가오카기쥬츠가가쿠다이가쿠 Substrate processing method and substrate processing apparatus

Also Published As

Publication number Publication date
JP2000281495A (en) 2000-10-10

Similar Documents

Publication Publication Date Title
JP2017095346A (en) Composite oxide sintered body and sputtering target consisting of the same
Wang et al. Effects of Na content on structural and optical properties of Na-doped ZnO thin films prepared by sol–gel method
Wang et al. Influence of thickness and annealing temperature on the electrical, optical and structural properties of AZO thin films
US20190112703A1 (en) Method of manufacturing oxide crystal thin film
Hiramatsu et al. Superconductivity in epitaxial thin films of Co-doped SrFe2As2 with bilayered FeAs structures and their magnetic anisotropy
Alam et al. Preparation and properties of transparent conductive aluminum-doped zinc oxide thin films by sol–gel process
Kim et al. Epitaxial growth of Al-doped ZnO thin films grown by pulsed laser deposition
Lee et al. Transparent conducting ZnO: Al, In and Sn thin films deposited by the sol–gel method
Yang et al. Room-temperature deposition of transparent conducting Al-doped ZnO films by RF magnetron sputtering method
US7867636B2 (en) Transparent conductive film and method for manufacturing the same
Srinivasan et al. Li doped and undoped ZnO nanocrystalline thin films: a comparative study of structural and optical properties
KR101410598B1 (en) Laminate, method for producing same, and functional element using same
KR101701237B1 (en) Lare-size Single-crystal Monolayer Graphene and Manufacturing Method Thereof
TWI481564B (en) In-Ga-Zn-O sputtering target
CN105924137B (en) In-Ga-Sn oxide sintered body, target, oxide semiconductor film, and semiconductor element
Krunks et al. Zinc oxide thin films by the spray pyrolysis method
Lai et al. Sol-gel processing of lead-free (Na, K) NbO 3 ferroelectric films
TWI532862B (en) A sputtering target, a method for forming an amorphous oxide film using the same, and a method for manufacturing a thin film transistor
JP4537434B2 (en) Zinc oxide thin film, transparent conductive film using the same, and display element
Singh et al. Comparison of the structural and optical properties of ZnO thin films deposited by three different methods for optoelectronic applications
EP1489654B1 (en) METHOD OF MANUFACTURING LnCuO(S, Se, Te) MONOCRYSTALLINE THIN FILM
Ammaih et al. Structural, optical and electrical properties of ZnO: Al thin films for optoelectronic applications
KR102027127B1 (en) In-Ga-Zn-O-BASED OXIDE SINTERED BODY SPUTTERING TARGET WITH EXCELLENT STABILITY DURING LONG-TERM DEPOSITION
Cao et al. Highly transparent and conducting fluorine-doped ZnO thin films prepared by pulsed laser deposition
Swapna et al. Microstructural, electrical and optical properties of ZnO: Mo thin films with various thickness by spray pyrolysis

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20060301

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20080616

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20080715

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20080916

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20081216

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20081219

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111226

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111226

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121226

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121226

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131226

Year of fee payment: 5

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

EXPY Cancellation because of completion of term