Film forming apparatus, thin film forming method, element manufacturing method, electronic device manufacturing method, and electronic equipment manufacturing method

Abstract

To provide a film deposition apparatus that can deposit a homogeneous crystal film and has excellent film deposition efficiency.SOLUTION: A film deposition apparatus includes two or more ICP generators installed between a substrate and a metal source of a thin film to form a thin film on the substrate under vacuum or decompressing environment. The two or more ICP generators are disposed while facing each other. The ICP generator has a substantially concave surface shape or parabolic shape curved on the center side of the substrate.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a film forming apparatus for forming a thin film. [Background technology]

[0002] Piezoelectric thin films made of lead zirconate titanate (Pb(Zr,Ti)O3) (hereinafter referred to as PZT), which has excellent piezoelectric and ferroelectric properties, are being investigated, and piezoelectric thin films are being applied to memory elements such as non-volatile memory (FeRAM), and MEMS (Micro Electro Mechanical Systems) technologies such as inkjet heads and acceleration sensors.

[0003] In recent years, it has been studied to form a (200) oriented Pt film on a (100) oriented Si substrate via a (200) oriented ZrO2 film or the like, thereby forming a piezoelectric film with good piezoelectric properties on the Pt film (Patent Document 1). However, even with reactive deposition equipment, the film quality of the piezoelectric film is still not satisfactory, and the yield is poor, which hinders mass production, and therefore there has been a demand for improvements in film formation equipment such as reactive deposition equipment. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-154015 A Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a film formation apparatus capable of forming a uniform crystal film and having excellent film formation efficiency. [Means for solving the problem]

[0006] As a result of intensive research into achieving the above-mentioned object, the inventors have discovered that when a crystalline film and a piezoelectric film are formed using a film formation apparatus in which two or more ICP generators are installed between a substrate and a metal source of a thin film and the thin film is formed on the substrate under vacuum or reduced pressure, and two or more of the ICP generators are arranged facing each other, a uniform crystalline film can be obtained with good yield in a short period of time, and have found that such a film formation apparatus can solve the above-mentioned conventional problems in one fell swoop. After obtaining the above findings, the present inventors conducted further studies and completed the present invention.

[0007] That is, the present invention relates to the following inventions. [1] A film formation apparatus in which two or more ICP generators are installed between a substrate and a metal source of a thin film, and the thin film is formed on the substrate under vacuum or reduced pressure, the two or more ICP generators being arranged opposite each other. [2] The film formation apparatus according to [1], wherein the ICP generator has a substantially concave curved shape or a parabolic shape curved toward the center of the substrate. [3] The deposition apparatus according to [1] or [2], wherein the ICP generator comprises a first electrode that generates plasma by applying a high-frequency voltage, and a second electrode that applies DC and / or AC excitation current through an RF cut filter. [4] The film formation apparatus according to any one of [1] to [3], further comprising an ion acceleration means between the substrate and the metal source, the ion acceleration means being inclined with respect to the substrate and the metal source. [5] The film formation apparatus according to [4], wherein the tilt angle is 1° to 35° with respect to the substrate. [6] The film formation apparatus according to any one of [1] to [5], further comprising a substrate support for supporting the substrate, and a high frequency power supply for substrate bias connected to the substrate support, wherein a low frequency power supply for substrate bias and a DC and / or AC power supply for substrate bias are connected to the substrate support, the low frequency power supply for substrate bias has a first electrode for generating plasma by applying a low frequency voltage, and the DC and / or AC power supply for substrate bias has a third electrode for applying DC and / or AC excitation current through an RF cut filter. [7] The film formation apparatus according to any one of [1] to [6], further comprising a heater provided in the vicinity of the substrate, the heater being alternately turned on and off. [8] The film formation apparatus according to any one of [1] to [7], wherein the ICP generator further comprises a means for irradiating the substrate with light of two or more different wavelengths. [9] A method for forming a thin film using a film formation apparatus, characterized in that the film formation apparatus is the film formation apparatus described in any one of [1] to [8] above.

[10] The method for forming a thin film according to [9], wherein the film formation apparatus is the film formation apparatus according to any one of [1] to [8], the thin film is a metal nitride film, and the ICP generator further has a means for irradiating the substrate with ultraviolet light.

[11] The method for forming a thin film according to [9], wherein the film formation apparatus is the film formation apparatus according to any one of [1] to [8], the thin film is a metal oxide film, and the ICP generator further has a means for irradiating the substrate with infrared rays.

[12] A method for producing a device including a thin film, the method comprising forming the thin film by the method for forming a thin film according to any one of [9] to

[11] above.

[13] The method according to

[12] above, wherein the element is a piezoelectric element or a semiconductor element.

[14] A method for producing an electronic device including an element, comprising producing the element by the method according to

[12] or

[13] above.

[15] A method for manufacturing an electronic device including an electronic device, the method comprising the steps of: manufacturing the electronic device by the manufacturing method described in

[14] above. Effect of the Invention

[0008] The film formation apparatus of the present invention has the effect of being capable of forming a uniform crystalline film and having excellent film formation efficiency. [Brief description of the drawings]

[0009] [Figure 1] 1 is a diagram showing a schematic diagram of a film forming apparatus according to a preferred embodiment of the present invention; [Diagram 2] FIG. 1 is a diagram showing a schematic diagram of an example of an embodiment of an ICP generator suitably used in the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing another example of an embodiment of an ICP generator suitably used in the present invention. [Figure 4] FIG. 2 is a schematic diagram showing another example of an embodiment of an ICP generator suitably used in the present invention. [Diagram 5] FIG. 2 is a schematic diagram showing another example of an embodiment of an ICP generator suitably used in the present invention. [Figure 6] 1 is a diagram illustrating a preferred embodiment of a MEMS transducer according to the present invention. [Figure 7] FIG. 1 is a schematic diagram showing an example of a cross-sectional view of a portion of a wafer provided with a piezoelectric actuator, as a suitable application example of the present invention to a fluid discharge device. [Figure 8] FIG. 2 is a diagram illustrating a film forming apparatus according to another preferred embodiment of the present invention. [Figure 9] FIG. 2 is a diagram illustrating a film forming apparatus according to another preferred embodiment of the present invention. [Figure 10] FIG. 2 is a diagram illustrating a film forming apparatus according to another preferred embodiment of the present invention. [Figure 11] FIG. 2 is a diagram illustrating a film forming apparatus according to another preferred embodiment of the present invention. [Figure 12]FIG. 2 is a diagram illustrating a film forming apparatus according to another preferred embodiment of the present invention. [Figure 13] FIG. 2 is a diagram showing the results of XRD measurement in the examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The film formation apparatus of the present invention is an apparatus for forming a thin film on a substrate under vacuum or reduced pressure, in which two or more ICP generators are installed between the substrate and a metal source of the thin film that serves as a raw material supply source, and is characterized in that the two or more ICP generators are arranged opposite each other.

[0011] In the present invention, it is preferable that an ICP generator, which is an ICP means, is installed between the substrate and the metal source of the thin film, and it is more preferable that the ICP generator has a first electrode that generates plasma by applying a high-frequency voltage, and a second electrode that applies a DC and / or AC excitation current through an RF cut filter, because this makes it easier to achieve uniform film quality and high-quality crystals.

[0012] In the present invention, it is preferable that an ion acceleration means is included between the substrate and the raw material supply source, and the ion acceleration means is inclined with respect to the substrate and the raw material supply source. A suitable means for inclining the ion acceleration means with respect to the substrate and the raw material supply source is, for example, a means for appropriately adjusting the inclination angle, output, and inclination of the substrate, in which the ICP generator is configured to have a substantially concave curved shape or parabolic shape curved toward the center of the substrate, and the orientation of the opening surface is inclined with respect to the direction from the raw material supply source to the substrate. In the present invention, the inclination angle in the inclination is preferably 0.1° to 89° with respect to the substrate, and more preferably 0.2° to 35°. According to such a preferable range, it is possible to easily improve the functionality of the thin film (particularly the piezoelectricity of the piezoelectric film).

[0013] In addition, in the present invention, a film formation apparatus for forming a crystalline film by crystal growth on the substrate via a buffer layer containing at least Hf preferably has a means for performing the crystal growth while tilting a substrate support that supports the substrate, since this makes it easier to achieve high quality, particularly of the crystalline film containing Hf.

[0014] Furthermore, in the present invention, an ICP generator is installed as the ICP means between the substrate and the metal source of the thin film, and the ICP generator has a generally concave curved shape or a parabolic shape curved toward the center of the substrate, which is preferable because it further improves the homogenization of film quality and the high quality of crystals, and makes it easier to achieve homogenization of film quality and high quality of crystals, especially for large areas of 8 inches or more, preferably 10 inches or more.

[0015] In the present invention, two or more ICP generators are installed as the ICP means between the substrate and the metal source of the thin film, and the two or more ICP generators are preferably arranged so as to face each other, since this makes it easier to achieve uniform film quality and high crystal quality.

[0016] In the present invention, it is preferable that a heater is provided near the substrate and that a means is included for alternately turning the heater on and off. By adopting such a preferable configuration, crystal growth can be more effectively promoted.

[0017] In the present invention, it is preferable that the ICP generator further includes a means for irradiating the substrate with light of two or more different wavelengths, and by adopting such a configuration, even when different crystal films, for example, an oxide film and a nitride film, are grown, slowing or stagnation of crystal growth due to the wavelength can be avoided, and the crystal growth of each film can be promoted more effectively. For example, in the present invention, it is preferable that the thin film is a metal nitride film, and the ICP generator further includes a means for irradiating the substrate with ultraviolet light, and it is also preferable that the thin film is a metal oxide film, and the ICP generator further includes a means for irradiating the substrate with infrared light.

[0018] The film forming apparatus of the present invention will be described below with reference to the drawings, but the present invention is not limited to these specific examples.

[0019] An example of a suitable embodiment of the film formation apparatus of the present invention is shown in Fig. 1. The film formation apparatus of Fig. 1 at least includes metal sources 1a-1b, earths 2a-2h, ICP electrodes 3a-3b, cut filters 4a-4b, DC power sources 5a-5b, RF power sources 6a-6b, lamps 7a-7b, Ar source 8, reactive gas source 9, power source 10, substrate holder 11, substrate 12, cut filter 13, ICP ring 14, vacuum chamber 15, and rotation shaft 16 in a crucible.

[0020] The ICP electrodes 3a and 3b in Fig. 1 have a substantially concave curved shape or a parabolic shape curved toward the center of the substrate 12. Suitable examples of the shape of the ICP generator having a substantially concave curved shape or a parabolic shape include the substantially concave curved ICP generator shown in Fig. 2 and the parabolic ICP generators shown in Figs. 3 to 5. As shown in Fig. 1, the ICP electrode is installed such that the opening surface of the ICP electrode having a substantially concave curved shape or a parabolic shape curved toward the center of the substrate 12 is inclined with respect to the film formation surface of the substrate.

[0021] As shown in Fig. 1, the substrate 12 is fixed on the substrate holder 11. Next, the rotating shaft 16 is rotated using the power supply 10 and a rotating mechanism (not shown) to rotate the substrate 12. The substrate 12 is heated by the lamps 7a-7b, and the inside of the vacuum chamber 15 is evacuated to a vacuum or reduced pressure by a vacuum pump (not shown). Thereafter, Ar gas is introduced from the Ar source 8 into the vacuum chamber 15, and argon plasma is formed on the substrate 12 using the DC power supplies 5a-5b, the RF power supplies 6a-6b, the ICP electrodes 3a-3b, the cut filters 4a-4b, and the earths 2a-2h, thereby cleaning the surface of the substrate 12.

[0022] Ar gas is introduced into the vacuum chamber 15, and a reactive gas is introduced using the reactive gas source 9. At this time, the lamps 7a to 7b, which are lamp heaters, are alternately turned on and off repeatedly, so that a crystal growth film of better quality can be formed.

[0023] Another example of a preferred embodiment of the film forming apparatus of the present invention is shown in Fig. 8. Fig. 8 differs from Fig. 1 in that DC power supplies 5c-5d, RF power supplies 6c-6d, ICP electrodes 3a-3b, ICP electrodes 3c-3d, cut filters 4c-4d, and earths 2g-2j are used near the substrate 12. With this configuration, crystal growth on the substrate 12 becomes better, and homogenization of the crystal film can be more easily achieved.

[0024] 9 is different from the film formation apparatus shown in Fig. 8 in that an electron gun 118 capable of irradiating an electron beam toward the substrate 12 and a RHEED (reflection high energy electron diffraction) screen 117 for observing a diffraction image by receiving the electron beam reflected by the substrate 12 are provided in the vacuum chamber 11, and an infrared radiation temperature detector (pyrometer) 119 is also provided in the vacuum chamber 11. The pyrometer 119 measures the surface temperature of the substrate 12 through a window provided in front of the substrate 12. This pyrometer 119 performs the measurement by, for example, opening a shutter (not shown) provided at the opening of the window.

[0025] An example of a preferred embodiment of the sputtering apparatus of the present invention is shown in Fig. 10. The sputtering apparatus of Fig. 10 includes at least earths 2a-2d, ICP electrodes 3a-3b, cut filters 4a-4b, DC power sources 5a-5b, RF power sources 6a-6b, lamps 7a-7b, reactive gas source 9, substrate 12, vacuum chamber 15, rotating shaft 16, target 220, substrate support 221, and heater 227. The side of substrate support 221 is tapered, and a tapered portion 221a is formed. This configuration not only makes maintenance easier, but also ensures installation space at a position suitable for film formation of lamps 7a-7b, and by combining with ICP electrodes 3a-3b, the quality of film formation can be improved.

[0026] The ICP electrodes 3a and 3b in Fig. 1 have a generally concave curved shape or a parabolic shape curved toward the center of the substrate 12. Suitable examples of the shape of the ICP generator having a generally concave curved shape or a parabolic shape include the ICP generator having a generally concave curved shape shown in Fig. 2 and the parabolic ICP generators shown in Figs. 3 to 5.

[0027] The film forming apparatus in Fig. 11 is different from the film forming apparatus shown in Fig. 1 in that hidden earths 302a and 302b are connected to the ICP electrodes 3a and 3b, respectively, and the cut filters 4a and 4b are configured to be positively charged. This configuration makes it easier for the crucible to be negatively charged, improving the generation of film-forming metal raw materials from the metal sources 1a and 1b.

[0028] The film forming apparatus can easily and with high quality manufacture a laminate structure in which at least a first layer and a second layer are laminated on a crystal substrate, the first layer being made of a metal compound film, the second layer being made of a metal film of a metal that transforms into martensitic form by heat treatment or processing, and the crystal substrate, the first layer, and the second layer being oriented in substantially the same crystal axis direction. The crystal axis direction is not particularly limited, but is preferably the (100) or (111) direction, and more preferably the (100) direction.

[0029] The metal is not particularly limited as long as it is a metal that undergoes martensitic transformation by heat treatment or processing, and may be a known metal. The metal is usually contained in the metal film as a main component of the metal film. Examples of the metal that undergoes martensitic transformation include Fe-Cr-Ni, Fe, Fe-Ni, Fe-Ni-Co, Fe-Si, Fe-Cr, Fe-Mn, Fe-Mn-C, Fe-Mn-Ni, Fe-Mn-Cr, Fe-C, Fe-N, Fe-Ni-C, Fe-Cr-C, Fe-Cu-C, Fe-Si-C, Fe-Cr-Ni-C, Co, Co-Ni, Co-Fe, Examples of the metal include Mn-Cu, In-Tl, In-Tl-Li, Na, Zr, Tl, Hf, Ti, Ti-Al, Ti-Cu, Ti-Cr, Ti-Fe, Ti-Mn, Ti-Mo, Ti-V, Ti-Zr, Ti-Al-V, Zr-U, Cu-Al-Ni, Cu-Al, Ag-Cd, Au-Cd, Au-Cd-Cu, Li, Li-Mg, Cu-Zn, U, U-Cr, and Hg. In the present invention, the metal preferably contains Fe, Cr, or Ni, more preferably contains Fe and Cr, and more preferably is stainless steel. According to such a preferred range, the bending strength can be improved. The "main component" may be any metal whose atomic ratio in the metal film is 0.5 or more. In the present invention, the atomic ratio of the metal to all metal elements in the metal film is preferably 0.7 or more, more preferably 0.8 or more.

[0030] In the present invention, the metal film is preferably oriented in the (100) direction. The "oriented in the (100) direction" means that the crystal orientation angle detected by X-ray diffraction is oriented in the (100) direction, and more specifically, the peak ratio in the (100) direction to the total peaks of the metal film detected by X-ray diffraction is 50% or more, and preferably the peak ratio is 90% or more.

[0031] In the present invention, the thickness of the metal film is preferably 100 μm or less, and more preferably 1 μm to 10 μm, which is preferable because the metal film is superior as an intermediate film for crystal growth of the functional film.

[0032] The metal film can be easily obtained by forming a metal compound film containing Hf and / or Zr by crystal growth as a first layer in the (100) direction on a crystalline substrate such as a Si substrate, and then forming the metal film by crystal growth as a second layer. This is a new finding made by the present inventors. The metal compound film is preferably an oxide or nitride containing Hf and / or Zr, and more preferably a nitride containing Hf and / or Zr.

[0033] The crystal substrate (hereinafter, simply referred to as "substrate") is not particularly limited as long as the object of the present invention is not hindered, such as the substrate material, and may be a known crystal substrate. It may be an organic compound or an inorganic compound. In the present invention, it is preferable that the crystal substrate contains an inorganic compound. In the present invention, it is preferable that the substrate has crystals on a part or all of the surface, more preferably a crystal substrate having crystals on all or a part of the main surface on the crystal growth side, and most preferably a crystal substrate having crystals on the entire main surface on the crystal growth side. The crystal is not particularly limited as long as the object of the present invention is not hindered, and the crystal structure is not particularly limited, but it is preferable that it is a cubic, tetragonal, trigonal, hexagonal, orthorhombic, or monoclinic crystal, and more preferably a crystal oriented in (100) or (200). In addition, the crystal substrate may have an off angle, and examples of the off angle include an off angle of 0.2° to 12.0°. Here, the "off angle" refers to the angle between the substrate surface and the crystal growth surface. The shape of the substrate is not particularly limited as long as it is plate-like and serves as a support for the epitaxial film. It may be an insulating substrate or a semiconductor substrate, but in the present invention, the substrate is preferably a Si substrate, more preferably a crystalline Si substrate, and most preferably a crystalline Si substrate oriented in (100). In addition to the Si substrate, examples of the substrate material include one or more metals belonging to Groups 3 to 15 of the periodic table or oxides of these metals. The shape of the substrate is not particularly limited, and may be an approximately circular shape (e.g., a circular shape, an elliptical shape, etc.) or a polygonal shape (e.g., a triangular shape, a square shape, a rectangular shape, a pentagonal shape, a hexagonal shape, a heptagonal shape, an octagonal shape, a nonagonal shape, etc.), and various shapes can be suitably used. In addition, in the present invention, a large-area substrate can be used, and the area of ​​the epitaxial film can be increased by using such a large-area substrate.

[0034] In the present invention, the crystal substrate preferably has a flat surface, but it is also preferable that the crystal substrate has an uneven shape on a part or all of the surface, since this can improve the quality of the crystal growth of the epitaxial film. The crystal substrate having the uneven shape may have an uneven portion consisting of a concave or convex portion formed on a part or all of the surface, and the uneven portion is not particularly limited as long as it is composed of a convex portion or a concave portion, and may be an uneven portion consisting of a convex portion, an uneven portion consisting of a concave portion, or an uneven portion consisting of a convex portion and a concave portion. The uneven portion may be formed of regular convex portions or concave portions, or may be formed of irregular convex portions or concave portions. In the present invention, it is preferable that the uneven portion is formed periodically, and it is more preferable that the uneven portion is patterned periodically and regularly. The shape of the uneven portion is not particularly limited, and examples thereof include a stripe shape, a dot shape, a mesh shape, and a random shape, but in the present invention, a dot shape or a stripe shape is preferable, and a dot shape is more preferable. Furthermore, when the unevenness is patterned periodically and regularly, the pattern shape of the unevenness is preferably a polygonal shape such as a triangle, a quadrangle (e.g., a square, a rectangle, or a trapezoid), a pentagon, or a hexagon, a circle, an ellipse, or the like. When the unevenness is formed in a dot shape, the lattice shape of the dots is preferably a lattice shape such as a square lattice, an oblique lattice, a triangular lattice, or a hexagonal lattice, and more preferably a triangular lattice shape. The cross-sectional shape of the recesses or protrusions of the unevenness is not particularly limited. Examples of the shape include, but are not limited to, a U-shape, an inverted U-shape, a wave shape, and a polygonal shape such as a triangle, a quadrangle (for example, a square, a rectangle, or a trapezoid), a pentagon, or a hexagon. The thickness of the crystal substrate is not particularly limited, but is preferably 50 to 2000 μm, and more preferably 100 to 1000 μm.

[0035] The piezoelectric layer is not particularly limited as long as it is a piezoelectric layer made of a piezoelectric material. The piezoelectric material may be a known piezoelectric material, but in the present invention, it is preferable that the piezoelectric material contains Pb and Ti. The semiconductor layer is not particularly limited as long as it is a semiconductor layer made of a semiconductor. The semiconductor may be a known semiconductor, but in the present invention, it is preferable that the semiconductor contains Si, SiC, GaN, or Ga2O3. In this specification, the terms "film" and "layer" may be interchangeable depending on the case or situation.

[0036] In the present invention, the piezoelectric layer or the semiconductor layer is preferably laminated on the second layer via a third layer and a fourth layer. The third layer is preferably made of a metal different from the metal, and the fourth layer is preferably made of a conductive metal oxide. Examples of the metal in the third layer include gold, silver, platinum, palladium, silver-palladium, copper, nickel, and alloys thereof. In the present invention, the third layer preferably contains a metal belonging to Group 10 or Group 11 of the periodic table, and more preferably contains platinum.

[0037] The conductive metal oxide is not particularly limited as long as it does not impede the object of the present invention, and may be any known conductive metal oxide. In the present invention, however, it is preferable that the conductive metal oxide contains Sr and / or Ru, and it is more preferable that the conductive metal oxide is an SRO film containing Sr and Ru.

[0038] The first layer, the second layer, the third layer, and the fourth layer can be laminated by using a known film forming means. In the present invention, the film forming means is preferably deposition (including MBE) or sputtering. The thickness of each layer is not particularly limited, but is preferably 10 nm to 100 μm, and more preferably 50 nm to 30 μm.

[0039] The metal film or laminated structure obtained as described above is preferably used for elements such as piezoelectric elements or semiconductor elements by using known means. The elements are also preferably used for electronic devices according to conventional methods. For example, the laminated structure can be connected to a power source or an electric / electronic circuit as a piezoelectric element, and mounted on a circuit board or packaged to form various electronic devices. In the present invention, the electronic device is preferably a piezoelectric device, and can be used as a piezoelectric device in electronic devices such as inkjet printer heads, microactuators, gyroscopes, and motion sensors. For example, if an amplifier and a rectifier circuit are connected and packaged, the electronic device can be used for various sensors such as magnetic sensors. The electronic device can also be applied to constant voltage driven memories, and for example, if a storage element and a rectifier power management circuit are connected, the electronic device can become an energy conversion device (energy harvester) that generates power from an external magnetic field or vibration. The energy conversion device is incorporated and used in a power supply system or a wearable terminal (earphone / hearable device, smart watch, smart glasses (eyeglasses), smart contact lenses, cochlear implants, cardiac pacemakers, etc.). In the present invention, the laminated structure is preferably used in, for example, smart glasses, AR headsets, MEMS mirrors for LiDAR systems, piezoelectric MEMS ultrasonic transducers (PMUTs) for advanced medical applications, and piezo heads for commercial and industrial 3D printers.

[0040] The electronic device is suitably used in electronic devices in the usual manner, and can be applied to various electronic devices other than the above-mentioned electronic devices, and more specifically, suitable examples include liquid ejection heads, liquid ejection devices, vibration wave motors, optical devices, vibration devices, imaging devices, piezoelectric acoustic parts, audio playback devices having the piezoelectric acoustic parts, audio recording devices, mobile phones, various information terminals, and the like.

[0041] Furthermore, the electronic device is also applied to a system in the usual manner, and an example of such a system is a sensor system. EXAMPLES

[0042] Example 1 The crystal growth surface side of the Si substrate (100) was treated by RIE, and in the presence of nitrogen, the metal of the deposition source was thermally reacted with nitrogen in the film formation apparatus of Figure 1 to form HfZrO single crystals on the Si substrate. The conditions of the deposition method during this film formation were as follows. Although not shown, the output and the orientation of the substrate relative to the deposition source were appropriately adjusted based on the angle between the ICP generator and the substrate, such as by slightly tilting the substrate, to form the film. Vapor deposition source: Hf, Zr Voltage: 3.5~4.75V Pressure: 3×10 -2 ~6×10 -2 Pa Substrate temperature: 450~700℃

[0043] Next, a SUS304 single crystal film was formed in the same manner as above, except that Fe, Cr and Ni were used as the metals of the deposition source.

[0044] Next, a platinum (Pt) metal film was formed as a conductive film on the single crystal film of the crystalline metal oxide by sputtering under the following conditions. Equipment: ULVAC sputtering equipment QAM-4 Pressure: 1.20×10 -1 Pa Target: Pt Power: 100W(DC) Thickness: 100nm Substrate temperature: 450~600℃

[0045] Next, an SRO film was formed on the conductive film by sputtering under the following conditions. Equipment: ULVAC sputtering equipment QAM-4 Power: 150W(RF) Gas: Ar Pressure: 1.8Pa Substrate temperature: 600℃ Thickness: 20nm

[0046] Next, a PbTiO3 film was formed as a piezoelectric film on the SRO film. The obtained laminated structure had good adhesion and crystallinity. In addition, the crystal substrate of the laminated structure, the single crystal film of the crystalline metal oxide, and the conductive film were measured for their crystallinity using an X-ray diffraction device. Figure 2 shows the XRD measurement results. As is clear from Figure 2, a SUS304 single crystal film with good crystallinity was formed, and the crystallinity of the PbTiO3 film and the like was also good. In addition, when the inclination angle of the single crystal film was measured using an X-ray diffraction device, as shown in Figure 13, the (002) plane corresponding to the film formation surface was inclined at 8.5°. In addition, when the inclination angle (0.1° to 89°) of the ICP generator of the film formation apparatus of Figure 1 was changed, it was found that there was a corresponding relationship with the inclination of the crystalline film. In particular, there was a linear relationship at 0.2° to 35°. This shows that it is possible to easily impart an inclination to the crystalline film by adjusting the inclination angle using the film formation apparatus of Figure 1. In addition, the crystallinity of the obtained film was evaluated using an X-ray diffraction device, including the difference with a film that was not tilted. As a result, it was found that by forming the film with the ion acceleration means tilted, the crystallinity was improved, and not only the crystallinity but also the performance of the functional film could be significantly improved.

[0047] (Test Example) As a test example, a cantilever beam of a microelement as shown in Figures 3 and 4 was fabricated using FIB FB2100 (Hitachi High-Technologies), and its fracture strength characteristics were evaluated using a nanoindenter NanoTest Xtreme (Micro Materials), as shown in Figure 5. Figure 5 shows that the fracture strength of Si was approximately 1 GPa, which was a nearly constant value. Considering that the bending strength of Si single crystal bulk material is approximately 300 MPa (paper), it was found that micromaterials have great strength. Furthermore, in the case of SUS304 single crystal thin film, the fracture strength was approximately 5 GPa, which is approximately 5 times the bending strength of Si single crystal. This means that by using SUS304 single crystal thin film for the beam of a MEMS device (movable part, equivalent to the active layer of an SOI substrate), it is expected that the displacement amount of the MEMS device will be significantly improved, as well as the life characteristics will be significantly improved.

[0048] (Examples) Examples of applications of the obtained laminated structure will be described in more detail below with reference to the drawings, but the present invention is not limited to these examples. In the present invention, unless otherwise specified, a piezoelectric device or the like can be manufactured from the laminated structure by using known means.

[0049] 6 shows an embodiment of an acoustic MEMS transducer constituting a MEMS microphone in which the laminate structure of the present invention is preferably used. The MEMS transducer can constitute an acoustic emission device (e.g., a speaker, etc.).

[0050] The MEMS microphone configured with the acoustic MEMS transducer of FIG. 6 shows a cantilever type MEMS microphone, and includes a Si substrate 21 having two cantilever beams 28A, 28B and a cavity 30. Each of the cantilever beams 28A, 28B is fixed to the substrate 21 at each end, and a gap 9 is provided between the cantilever beams 8A, 8B. The cantilever beams 8A, 8B are formed, for example, by a laminated structure including a plurality of piezoelectric layers (PZT films) 26a, 26b, and are alternated with a plurality of electrode layers, i.e., Pt films 24a, 24b, 24c and SRO films 25a, 25b, 25c, 25d. The Pt film 24a is provided on a SUS film 23, and the HfZrN film 23 is provided on the SUS film 23. Compared with the case of using SiO2, SiN, etc., the use of the HfZrN film 23 provides excellent adhesion and crystallinity with the Si substrate, and the crystallinity can be further improved up to the multiple layers thereon, and further provides excellent piezoelectric properties and durability.

[0051] FIG. 7 shows an example of application of the laminated structure of the present invention to a printing application, particularly to a fluid discharge device that can be used in the form of an inkjet printhead, and specifically shows a cross-sectional view of a portion of a wafer having a piezoelectric actuator including Pt films 34a, 34b and SRO films 35a, 35b as electrode layers and a PZT film 36 as a piezoelectric film. The wafer of FIG. 7 has a chamber 41 for containing a fluid in addition to the piezoelectric actuator. The chamber 41 is configured to take in a fluid from a tank (not shown) through a flow path 40. The wafer of FIG. 10 includes a Si substrate 31, on which a HfZrN film 32 and a SUS film 33 are laminated, facing the chamber 41. In FIG. 10, the HfZrN film 32 is used, which provides better adhesion and crystallinity with the Si substrate than when SiO2, SiN, or the like is used, and the crystallinity is further improved up to a plurality of layers thereon, and further provides better piezoelectric properties and durability. The HfZrN film 32 has, for example, a quadrangular shape in a top view (not shown), and this shape may be, for example, any of a square, a rectangle, a rectangle with rounded corners, a parallelogram, and the like.

[0052] On the SUS film 33, a Pt film 34a, an SRO film 35a, a piezoelectric film (PZT film) 36, an SRO film 35b, and a Pt film 34b are laminated in this order to form a piezoelectric actuator. The piezoelectric actuator further includes an insulating film 37 extending on the electrodes 34a and 35a, the piezoelectric film 36, and the electrodes 34b and 35b. The insulating film 37 includes a dielectric material used for electrical insulation, and such a dielectric material may be a known dielectric material, for example, a SiO2 layer, a SiN layer, or an Al2O3 layer. The thickness of the insulating layer including the insulating film as a constituent material is not particularly limited, but is preferably between about 10 nm and about 10 μm. The conductive path 39 is provided on the insulating layer (insulating film) 37 and contacts the electrodes 34a and 35a and the electrodes 34b and 35b, respectively, to enable selective access during use. The conductive path may be made of a known conductive material, and a suitable example of such a conductive material is aluminum (Al). The passivation layer 42 is provided on the insulating layer 37, the electrodes 34b and 35b, and the conductive path 39. The passivation layer 42 may be made of a dielectric material used for passivation of the piezoelectric actuator, and the dielectric material is not particularly limited and may be a known dielectric material. Suitable examples of the dielectric material include SiN and SiON (silicon oxynitrate). The thickness of the passivation layer is not particularly limited, but is preferably between about 0.1 μm and about 3 μm. The conductive pad 38 is also provided along the piezoelectric actuator and is electrically connected to the conductive path 39. The passivation layer 42 functions as a barrier layer that protects the piezoelectric body from moisture and the like. [Industrial Applicability]

[0053] The film forming apparatus of the present invention is useful for forming, for example, piezoelectric, semiconductor or functional crystal films, and is particularly suitable for forming crystal films used in piezoelectric elements and semiconductor elements. [Explanation of symbols]

[0054] 1a~1b Metal source 2a~2j Earth 3a~3b ICP electrode 4a~4b Cut Filter 5a~5b DC power supply 6a~6b RF power supply 7a~7b Lamps 8 Ar source 9. Reactive Gas Sources 10 Power supply 11 Circuit Board Holder 12 Substrate 13 Cut Filter 14 ICP Ring 15 Vacuum chamber 16 Rotation Axis 21 Crystalline substrate (Si substrate) 22 HfZrN film 23 SUS membrane 24a Pt membrane 24b Pt membrane 24c Pt membrane 25a SRO membrane 25b SRO membrane 25c SRO membrane 25d SRO membrane 26a PZT membrane 26b PZT membrane 28A Cantilever Beam 28B Cantilever beam 29 Gap 30 cavities 31 Crystalline substrate (Si substrate) 32 HfZrN film 33 SUS membrane 34a Pt membrane 34b Pt membrane 35a SRO membrane 35b SRO membrane 36 PZT membrane 37 Insulating Film 38 Conductive Pad 39 Conductive Path 40 Flow Path 41 Chamber 42 Passivation Layer 117 RHEED 118 Electron Gun 119 Pyrometer 220 Target 221 Substrate support 221a Tapered section 227 Heater 302a Hidden Earth 302b Hidden Earth 401 Raw material gas outlet 402 Mass Flow Controller 403 Raw Gas Source

Claims

1. A film formation apparatus for forming a thin film on a substrate under vacuum or reduced pressure, comprising: two or more ICP generators installed between a substrate and a metal source of the thin film; A film forming apparatus characterized in that two or more of the ICP generators are arranged opposite each other.

2. 2. The film deposition apparatus according to claim 1, wherein the ICP generator has a substantially concave curved surface or a parabolic shape curved toward the center of the substrate.

3. 3. The film forming apparatus according to claim 1, wherein the ICP generator comprises a first electrode that generates plasma by applying a high-frequency voltage to the first electrode, and a second electrode that applies a DC and / or AC excitation current through an RF cut filter.

4. 3. The film forming apparatus according to claim 1, further comprising an ion accelerating means between the substrate and the metal source, the ion accelerating means being inclined with respect to the substrate and the metal source.

5. 5. The film deposition apparatus according to claim 4, wherein the tilt angle is 1° to 35° with respect to the substrate.

6. 3. The film formation apparatus according to claim 1, further comprising: a substrate support for supporting the substrate; and a high-frequency power supply for substrate bias connected to the substrate support, wherein a low-frequency power supply for substrate bias and a DC and / or AC power supply for substrate bias are connected to the substrate support, the low-frequency power supply for substrate bias has a first electrode that generates plasma by applying a low-frequency voltage, and the DC and / or AC power supply for substrate bias has a third electrode that applies a DC and / or AC excitation current through an RF cut filter.

7. 3. The film forming apparatus according to claim 1, further comprising a heater provided in the vicinity of the substrate, and means for alternately turning on and off the heater.

8. 3. The film forming apparatus according to claim 1, wherein the ICP generator further comprises means for irradiating the substrate with light of two or more different wavelengths.

9. A method for forming a thin film using a film forming apparatus, wherein the film forming apparatus is the film forming apparatus according to claim 1 or 2.

10. The method for forming a thin film according to claim 9, wherein the thin film is a metal nitride film, and the ICP generator further comprises means for irradiating the substrate with ultraviolet light.

11. The method for forming a thin film according to claim 9, wherein the thin film is a metal oxide film, and the ICP generator further comprises means for irradiating the substrate with infrared rays.

12. A method for producing a device including a thin film, the method comprising forming the thin film by the method for forming a thin film according to claim 9.

13. 13. The method for producing an element according to claim 12, wherein the element is a piezoelectric element or a semiconductor element.

14. A method for fabricating an electronic device including an element, the method comprising fabricating the element by the method of claim 12.

15. A method for manufacturing an electronic device including an electronic device, the method comprising the steps of: manufacturing the electronic device by the method for manufacturing an electronic device according to claim 14.

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