IAD film-forming device

Abstract

To provide an ion-assisted film deposition apparatus for forming a dense film on each surface of a three-dimensional base material.SOLUTION: A film deposition apparatus includes a first rotation shaft 85 for rotatably supporting a base material holder 83, a rotation support shaft 86 for supporting those, and a first and a second ion guns. The base material holder rotates and revolves and the first rotation shaft inclines against a vertical direction. The base material has a high order part 61R and a low order part 61L. When a generally vertical surface against an axis line direction of the first rotation shaft is a first surface 611 and a generally parallel surface against the axis line of the first rotation shaft is a second surface 612, a first ion gun 15 is arranged downward in a high order part side, a second ion gun 93 is arranged downward in a low order part side, an evaporation source 16 is arranged between the first ion gun and the second ion gun, the first ion gun is arranged in a position attitude that an incident angle of an ion beam irradiated by the first ion gun to a first surface is 30° or less and an incident angle of an ion beam irradiated by the second ion gun to the second surface is 30° or less.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to an apparatus for forming a ceramic film on the surface of a substrate, and particularly to an apparatus for forming a film on the surface of a three-dimensional substrate using the ion assist deposition method (IAD: Ion Assist Deposition).

Background Art

[0002] In semiconductor manufacturing equipment used in semiconductor manufacturing, particularly in etching equipment, in order to suppress corrosion of components inside the equipment by fluorine-based plasma, a yttrium oxide film is formed as a corrosion-resistant protective film on the surface of the components. Conventionally, the spraying method has been used as a method for forming the corrosion-resistant protective film. As the miniaturization of semiconductor chips progresses, the requirements for particles have become stricter, and since the corrosion of the corrosion-resistant protective film causes particle generation, a protective film with stronger corrosion resistance to fluorine-based plasma than in the past has been required. The ion assist deposition method described in Patent Document 1 can form a protective film with strong corrosion resistance to fluorine-based plasma.

[0003] FIG. 1 is a conceptual diagram showing the configuration of a conventional IAD film forming apparatus. As shown in FIG. 1, the IAD film forming apparatus 11 includes a substrate holder 13, an ion gun 15, and evaporation sources 16 and 17 inside a vacuum chamber 12. The substrate holder 13 is installed near the ceiling inside the vacuum chamber 12 and is rotatable while holding the substrate 14. Under reduced pressure, a substance to be formed into a film (for example, yttrium oxide) from the evaporation source 16 is heated and melted, evaporated, and formed into a film on the surface of the substrate 14 disposed above. At the same time, the ionized gas from the ion gun 15 is irradiated toward the substrate 14 to modify the film. The characteristics of the film change depending on the irradiation amount of the ionized gas.

[0004] The kinetic energy of ionized gas modifies the deposited film, resulting in a dense, strong, and smooth-surfaced film. The efficiency of ion energy transfer is defined as the amount of kinetic energy transferred from the ionized gas to the film. As will be discussed later, ion energy transfer efficiency is (COSθ) 2 Since it is proportional to the effect, it is important to irradiate the substrate with ionized gas at an angle as close to perpendicular as possible to the film deposition surface. Since ions only travel in a straight line, the IAD method is mainly used to deposit films on objects with a nearly flat shape, such as lenses. On the other hand, many parts in etching equipment are three-dimensional, and the angle of incidence of ions becomes large when applied to the sides of these three-dimensional parts. For this reason, it has been recognized until now that it is not possible to deposit corrosion-resistant protective films that meet stringent requirements on the surface of three-dimensional parts using the IAD method.

[0005] As shown in Figure 4, the ion gun 40 consists of a quartz plasma discharge chamber 42, three lead electrodes 43-45, and an RF coil 46 for plasma generation, all housed in a stainless steel container 41. The container 41 has an outer diameter of approximately 20-30 cm and a height of approximately 20-30 cm. A gas introduction pipe 49 connects the outside of the container 41 to the inside of the plasma discharge chamber 42 and is used to introduce gases such as oxygen and argon into the plasma discharge chamber 42 from the outside of the container 51. Furthermore, high voltages of -1kV, +800V, and ground potential are applied to the three electrodes 43-45, and they are stacked with a gap of less than 1 mm between them, requiring extremely high assembly precision. In addition, a high-frequency application cable 47 and a high-voltage application cable 48 are connected, and all of these are installed and fixed as a single unit inside the vacuum chamber. If the installation position or angle needs to be changed, the high-voltage application wire and high-frequency cable must also be moved together while maintaining the assembly precision. For this reason, the installation position and angle were previously always fixed. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 63-171873 [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] The present invention provides a device that can effectively ionize all film-forming surfaces of a three-dimensional substrate. [Means for solving the problem]

[0008] According to one aspect of the present invention, An ion-assisted film deposition apparatus comprising: a vacuum chamber capable of maintaining a substantially vacuum state inside; an evaporation source for evaporating an evaporation material within the vacuum chamber; and a substrate holder for holding a substrate on which a thin film is formed by deposition of the evaporation material evaporated from the evaporation source, A first rotating shaft that rotatably supports the substrate holder, The base material holder and the second rotation support shaft that rotatably supports the first rotation shaft, The first ion gun irradiates with an ion beam, A second ion gun that irradiates with an ion beam, Equipped with, The aforementioned substrate holder rotates on its own axis and around its orbit (planetary rotation), The first axis of rotation is inclined with respect to the vertical, A portion of the substrate held by the substrate holder, the part that is relatively higher is designated as the higher portion, and the part that is relatively lower is designated as the lower portion. When the surface of the elevated portion is defined as follows: the surface substantially perpendicular to the axial direction of the first rotation axis is the first surface, and the surface substantially parallel to the axial direction of the first rotation axis is the second surface, The first ion gun is positioned below the upper part, The second ion gun is positioned below the lower part, The evaporation source is positioned between the first ion gun and the second ion gun. The first ion gun is positioned and orientation such that the angle of incidence of the upper portion of the ion beam irradiated from the first ion gun with respect to the first surface is 30° or less, and An ion-assisted film deposition apparatus is provided in which the second ion gun is installed in a position and orientation such that the incident angle of the upper portion of the ion beam irradiated from the second ion gun with respect to the second surface is 30° or less.

[0009] Figure 9 shows an example of the ion-assisted film deposition apparatus described above. The first rotating shaft 85 rotatably supports the base material holder 83. The rotating support shaft 86 rotatably supports the base material holder 83 and the first rotating shaft (rotation axis) 85. The base material holder 83 rotates on its axis and revolves around an orbit (planetary rotation). The first ion gun 15 and the second ion gun 93 irradiate with ion beams. The first axis of rotation 85 is inclined with respect to the vertical. The base material holder 83 is also inclined with respect to the vertical direction. As a result, the base material 61 held by the base material holder 83 has a relatively higher upper portion (the shaded area 61R to the right of the axis 861 of the rotation support shaft 86 in Figure 9) and a relatively lower lower portion (the shaded area 61L to the left of the axis 861 of the rotation support shaft 86 in Figure 9). A surface on the upper part that is substantially perpendicular to the axial direction of the first rotation axis is designated as the first surface 611, and a surface that is substantially parallel to the axial direction of the first rotation axis is designated as the second surface 612.

[0010] The first ion gun 15 is positioned below the upper part (shaded area 61R). The second ion gun 93 is positioned below the lower section (shaded section 61L). The evaporation source 16 is positioned between the first ion gun 15 and the second ion gun 93. The first ion gun 15 is positioned and orientationd such that the incident angle θ3 of the upper portion 61R of the ion beam irradiated from the first ion gun 15 with respect to the first surface 611 is 30° or less. The second ion gun 93 is installed in a position and orientation such that the incident angle θ5 of the high position portion 61R of the ion beam irradiated from the second ion gun 93 with respect to the second surface 612 is 30° or less.

[0011] The rotation support shaft 86 supports the substrate holder 83 and the first rotation shaft 85 so as to be rotatable (revolvable). The revolution speed (the overall rotation speed shown in FIG. 1) is 5 to 15 rpm. On the other hand, the rotation speed (rotation speed) about the first rotation shaft 85 is 10 to 50 rpm, preferably 15 to 25 rpm. Further, it is preferable that the rotation speed changes during film formation. It further includes an ion gun support base 94 that supports the second ion gun 93. Preferably, the ion gun support base 94 is vertically movable.

[0012] Furthermore, it is preferable to satisfy the following requirements 1) to 3). 1) The evaporation source 16 is disposed at the center and lower part of the vacuum chamber 12. The second ion gun 93 is disposed above the evaporation source 16. It further includes a deposition prevention plate 95 disposed below the second ion gun 93 and above the evaporation source 16.

[0013] 2) Two axes included in the X - Y plane parallel to the bottom surface of the vacuum chamber 12, with the axes perpendicular to each other being the X - axis and the Y - axis, When the axis included in the X - Z plane perpendicular to the X - Y plane and perpendicular to the X - axis is the Z - axis, The Z - coordinate value of the center of the first ion gun 15 and the Z - coordinate value of the center of the evaporation source 16 are substantially equal.

[0014] 3) On the X - Z plane (on the plane of FIG. 9), 「 Evaporation source 16 center point」 and 「a part of the low position portion (shaded portion 61L) that is closest to the axis 861 of the rotation support shaft 86」, when the straight line connecting them is defined as the deposition prevention line 96, A part 97 of the deposition prevention plate 95 that is closest to the axis 861, It is located on or closer to axis 861 than to the protective line 96. [Effects of the Invention]

[0015] By efficiently irradiating each surface of a three-dimensional substrate with ions, it becomes possible to form a dense, high-strength film with a smooth surface. [Brief explanation of the drawing]

[0016] [Figure 1] A conceptual diagram showing the configuration of a conventional IAD (Integrated Adsorption Deposition) film deposition system. [Figure 2] A diagram illustrating elastic scattering. [Figure 3] A diagram illustrating that the energy transferred to the film side differs depending on the size of the colliding atoms. [Figure 4] A schematic cross-sectional view showing an example of the structure of an ion gun. [Figure 5] A conceptual diagram showing the configuration of the IAD film deposition apparatus used in the example. [Figure 6] Top view and cross-sectional view of the film-forming substrate used in the example. [Figure 7] A conceptual diagram showing the substrate shown in Figure 6 mounted on a conventional IAD film deposition apparatus. [Figure 8] A conceptual diagram showing a substrate, as shown in Figure 6, mounted on a substrate holder that is tilted in the vertical direction. [Figure 9] A conceptual diagram showing the configuration of the IAD film deposition apparatus used in the example. [Figure 10] SEM images of the film surface at ion incidence angles θ = 0° to 60° in the reference example. [Figure 11] X-ray diffraction spectra of the film surface at ion incidence angles θ = 0° to 60° in the reference example. [Figure 12] SEM image of the film deposition surface when the ion current of the second ion gun was 700 mA. [Figure 13] A graph showing the relationship between θ, cosθ, and cos2θ. [Modes for carrying out the invention]

[0017] The invention will be described in detail below with reference to the drawings. Substantially identical components are denoted by the same reference numerals, and their descriptions are omitted. As shown in Figure 2, the incident angle θ of the incident ion is defined. If the velocity at incidence is V and the mass is m, the energy E⊥ that the ion imparts to the film is given by equation (1) below, and the film deposition rate S⊥ in the direction perpendicular to the film surface is given by equation (2) below. E⊥=m(Vcosθ) 2 / 2 formula (1) S⊥=Scosθ Equation (2) As the angle θ increases, the rate at which the energy E⊥ imparted to the film by ions decreases becomes larger than the rate at which the film deposition rate S⊥ decreases. Consequently, the film quality improvement effect from ion irradiation is lost.

[0018] However, this is the case of perfect elastic scattering. In actual film deposition, incident ions collide with atoms present on the film surface, so the energy transferred to the film side differs depending on the size of the colliding atoms. Figure 3 schematically shows the case when oxygen ions are irradiated onto a film surface containing oxygen and yttrium. Since the mass number of oxygen is 16 and the mass number of yttrium (Y) is 88.9, oxygen ions that collide with Y atoms in yttrium oxide (Y2O3) undergo a state close to elastic scattering, but oxygen ions that collide with oxygen atoms penetrate into the film. That is, almost all of the energy is transferred to the film. As a result, the ion irradiation angle dependence in IAD is E⊥=m(Vcosθ). 2 The angle dependence decreases rather than being 2. Furthermore, if the incident ion is larger, such as Ar ions, Kr ions, or Xe ions instead of oxygen ions, the angle dependence is expected to decrease even further. Therefore, the actual degree of angle dependence cannot be determined without performing film deposition and checking the results, and it is difficult to determine it quantitatively in theory.

[0019] The effect of incident ions on film quality (film quality improvement coefficient) is expressed by the following formula. Film quality improvement coefficient ∝ Incident ion voltage × Ion amount / Film deposition rate In other words, the film quality improvement coefficient is essentially determined by the ratio of the energy applied to the film (= incident ion voltage × ion amount) to the film deposition rate. In reality, the following two factors also have an influence. angle of incidence The mass difference between the incident ion and the atom it collides with.

[0020] Therefore, it is necessary to actually change the angle of ion incidence and measure how the film properties change according to the angle of incidence to determine the angle of incidence required to form a dense film. The following 1) to 3) were measured. 1) Membrane stress: As ion irradiation increases, the stress changes from tensile to compressive stress. 2) X-ray diffraction: As ion irradiation increases, the amorphous film changes into a crystalline film, and preferential orientation progresses. In this specification, "advancing preferential orientation" means an increase in the proportion of crystals oriented to a predetermined crystal plane. 3) Particle size on the SEM surface: As ion irradiation increases, the particles change from a random shape to a circular shape, and with further increases, the particle size decreases. By measuring and verifying these three items, the actual ion irradiation efficiency can be determined.

[0021] <Equipment used in the example> Using the IAD film deposition apparatus 51 shown in Figure 5, the evaporation source 16 for film deposition and the ion gun 15 were arranged in the same plane inside the vacuum chamber 12, and the substrate 14 was placed directly above the ion gun 15 to perform film deposition. • Distance D between the ion gun center and the evaporation source center: 300 mm • Distance T / S between the ion gun surface and the center of the substrate: 1000 mm The base material 14 is fixed to the base material holder 53 and rotates together with the base material holder 53. The angle of the base material holder (θ in the figure) can be set arbitrarily. The evaporation source 16 is a copper (Cu) hearth with a diameter of 30 mm. Y2O3 material was packed into the Cu hearth and irradiated with an electron beam to melt and evaporate the material. Ion gun 15 has a 200mmφ extraction electrode and a maximum output of 1300V and 1500mA. The extraction voltage is determined by the potential of the ion gun's electrode, and the current value was calibrated by actual measurement on the substrate. The substrate holder was rotated at a speed of 10 rpm.

[0022] <Reference example 1> Yttrium oxide was used as the deposition material, and deposition was performed by varying the incident angle θ while maintaining a standard condition of 1000V and 1200mA ion irradiation under a T / S of 1000mm and an incident angle θ=0°, resulting in a deposition rate of 2.5 Å / sec. The vacuum level before film deposition was 1.2 × 10⁻⁶. -4 Pa. The pressure during film deposition is 1.3 × 10⁻⁶. -2 The pressure was Pa. Although not shown in the diagram, the vacuum evacuation was performed using a four-stage configuration with a Meissner trap (-127°C), an oil diffusion pump, a mechanical booster pump, and an oil rotary pump. A 2mm thick alumina substrate was used as the base material, and the surface was polished to a Ra (arithmetic mean roughness: JIS B0601:2001) of 0.02 μm. The film deposition time was 6 hours. The conditions for the ion source were as follows: • Type of introduced gas: Oxygen gas • Inlet gas volume: 50 sccm (standard cubic centimeter per minute) Table 1 shows the film thickness and stress when the incident angle θ shown in Figure 5 was varied to 0°, 30°, 45°, and 60°. As shown in Table 1, at an incident angle of 0°, there was sufficient ion irradiation, resulting in strong compressive stress. However, as the incident angle increased, the compressive stress decreased and changed to tensile stress at 60°. This is because, as the incident angle increases, the ion irradiation decreases relative to the film deposition rate.

[0023] [Table 1]

[0024] Figures 10(a) to (d) show SEM images of the surface of films formed at incident angles θ = 0° to 60°. At an incident angle of 0°, the surface had very fine particle size, but as the incident angle increased from 15° to 30°, the particle size gradually increased. Random crystals began to be mixed in from an incident angle of 45°, and at an incident angle of 60°, the surface had uneven particle size.

[0025] Figures 11(a) to (d) show the X-ray diffraction spectra of films formed at incident angles θ = 0° to 60°. The vertical axis represents X-ray intensity (cps), and the horizontal axis represents the diffraction angle (measurement angle from 10° to 50°). As shown in Figure 11, at an incidence angle θ=0°, the film exhibited a perfect (111) preferred orientation, but at θ=15°, 30°, and 45°, other orientations were also present. On the other hand, at θ=60°, peaks of orthorhombic crystals, a different crystalline phase, appeared. The stable layer of yttrium oxide is BCC (cubic), but it is known to have an orthorhombic phase at high temperatures. Since vacuum deposition is performed in a thermally non-equilibrium state, it is thought that the high-temperature phase appeared in yttrium oxide at θ=60°. When yttrium oxide is sufficiently irradiated with ions, it forms a film with a preferred orientation in the (111) direction of the stable cubic (BCC) layer, but when the ion energy is insufficient, the preferred orientation breaks down and other orientations appear. Furthermore, it can be seen that if the ion energy is further insufficient, it becomes orthorhombic.

[0026] <Reference example 2> The film was deposited in the same manner as in Reference Example 1, except that the gases supplied to the ion gun were changed to "40 sccm of oxygen gas and 10 sccm of Ar gas". The results are shown in Table 2. Since the effect of ion irradiation can be understood by examining the film stress in Reference Example 1, only film thickness and stress will be explained below. By adding Ar gas to the gas flowing through the ion gun, the energy from ion irradiation increased at all angles, resulting in increased compressive stress.

[0027] [Table 2]

[0028] <Reference example 3> The film was deposited in the same manner as in Reference Example 1, except that the gases supplied to the ion gun were changed to "40 sccm of oxygen gas and 20 sccm of Ar gas". The results are shown in Table 3.

[0029] [Table 3]

[0030] In Reference Example 3, where the Ar gas flow rate was set to 20 sccm, the compressive stress increased even more at all angles compared to Reference Example 2, where the Ar gas flow rate was set to 10 sccm. Ionic energy is Cos 2 The deposition rate is proportional to θ, and the deposition rate is proportional to Cosθ. θ represents the ion incidence angle. Therefore, the ion energy transfer efficiency per unit deposition rate is Cos 2 θ / Cosθ = Cosθ, and the film quality decreases in proportion to Cosθ. The values ​​of Cosθ are shown in Table 4 and Figure 13, and they decrease sharply from around 30°. Therefore, it is preferable to set the angle of incidence of the ions to 30° or less.

[0031] [Table 4]

[0032] Figure 6 shows a top view and a cross-sectional view of the film-forming substrate used in the following embodiment. The substrate 61 shown in the figure is a ring-shaped substrate made of alumina sintered material. H1: 10mm, H2: 20mm ·D1:420mm, D2:600mm, D3:800mm The surfaces where film deposition is required are the bottom surface and the inner circumferential surface (side surface).

[0033] As shown in Figure 7, when the substrate 61 shown in Figure 6 is mounted on a conventional IAD deposition apparatus 71, the ion incidence angle θ2 to the inner surface inevitably becomes 45° or more, reducing the ion irradiation effect. In the IAD deposition apparatus 71 shown in Figure 7, the ion gun 15 is positioned to the left of the evaporation source 16. On the other hand, in the IAD deposition apparatus 11 shown in Figure 1, the ion gun 15 is positioned to the right of the evaporation source 16. In other words, the positions of the ion gun 15 and the evaporation source 16 are reversed left and right in the IAD deposition apparatus 11 shown in Figure 1 and the IAD deposition apparatus 71 shown in Figure 7.

[0034] Figure 8 shows another IAD film deposition apparatus 81. The substrate holder 83 of the IAD film deposition apparatus 81 can be set at any angle with respect to the vertical direction. In addition, the substrate holder 83 can rotate around the first rotation axis 85 as its axis of rotation and around the second rotation axis 86 as its axis of revolution during film deposition. • Distance D between the ion gun center and the evaporation source center: 300 mm • Distance T / S between the ion gun surface and the center of the substrate: 1000 mm As shown in Figure 8, even when the substrate 61 is held in the tilted substrate holder 83, it is impossible to simultaneously reduce both the angle of incidence θ3 to the bottom surface and the angle of incidence θ4 to 30° or less.

[0035] <Example 1> Figure 9 shows an IAD film deposition apparatus 91 further equipped with a second ion gun 93, an ion gun support base 94, and an anti-adhesion plate 95. • The inclination angle of the first axis of rotation 85 relative to the second axis of rotation 86 is θ6:30° • The tilt angle of the second ion gun 93 with respect to the vertical is θ7:37° • Distance D1 between the center of the first ion gun 15 and the center of the evaporation source 16: 300 mm • Distance D2 between the center of the second ion gun 93 and the center of the evaporation source 16: 300 mm • Distance T / S between the ion gun surface of the first ion gun 15 and the center of the substrate: 1000 mm • Distance H: 400 mm between the ion gun surface of the first ion gun 15 and the ion gun surface of the second ion gun 93 The second ion gun 93 is fixed to the ion gun support base 94 such that its inclination angle θ7 with respect to the vertical is 37°. As mentioned above, θ6 = 30° and θ7 = 37°, so the ion incidence angle θ5 from the second ion gun 93 to the inner surface is 23°. The ion incidence angle θ3 from the first ion gun 15 to the bottom surface is maintained at 30° or less. The ion gun support base 94 is movable up and down in the vertical direction. The structure of the second ion gun 93 is the same as that of the first ion gun 15 shown in Figure 4. The second ion gun 93 is fixed to the ion gun support base 94 along with the high-voltage and high-frequency wiring, and is vertically movable along with the high-voltage and high-frequency wiring.

[0036] As shown in Figure 9, by tilting the substrate 61 by 30° and adding a second ion gun 93, ion irradiation becomes possible on both the bottom surface and the inner circumferential surface at an incident angle of 30° or less. In order to maintain uniformity of film formation, the substrate needs to rotate (rotate and revolve) around two axes: the axis of rotation and the axis of revolution.

[0037] The IAD film deposition apparatus 91 used in Example 1 is a high-speed (IAD) vacuum thin film deposition apparatus MIC-1350 manufactured by Synchron Co., Ltd., with a second ion gun 93, the NIS-175, also manufactured by Synchron Co., Ltd., added to it. NIS-175 Ionization method: RF (Radio Frequency) excitation type Ion beam diameter: 175 mm Electrode shape: Dome type, 200mm diameter Ion energy: 100~1000eV Total ion current: 1200mA Outer diameter Φ310mm, height H210mm Neutralizer current: Maximum 2000mA

[0038] The manufacturers and product names of the film-forming materials are as follows: USTRON Co., Ltd. UKHYSJA01001-0 Y2O3, particle size 1-3 μm, purity 99.9% The film was formed on the bottom surface and inner circumferential surface of the substrate 61 under the following conditions. • During film deposition, the wall temperature inside the chamber was 120°C, and the substrate temperature was 300°C. • Gas supplied to the first ion gun 15: Oxygen gas 50 sccm • Gas supplied to the second ion gun 93: Oxygen gas 50 sccm

[0039] As shown in Figure 9, in the IAD film deposition apparatus 91, a protective plate 95 is installed below the ion gun 2. The protective plate 95 has two functions. Its primary function is to prevent film from adhering to the second ion gun 93. The second function is to prevent the film from adhering to the substrate 61 that has rotated towards the second ion gun 93, as indicated by the dashed-dotted line (anti-adhesion line) 96. This is to prevent the amount of film adhering to the bottom surface from becoming excessively large compared to the amount adhering to the inner surface. Although not shown in the diagram, the size of the anti-adhesion plate 95 is optimized for the substrate.

[0040] In this state, film deposition was carried out in the same manner as in Reference Example 1. A 10mm x 20mm rectangular, 1mm thick alumina test piece was fixed to the bottom surface and inner circumferential surface of the substrate 61, and the film formed on this test piece was evaluated. Compared to the film thickness formed in Reference Example 1 when the incident angle is 0°, the film thickness formed on the inner surface in Example 1 is expected to be approximately 20% lower. Therefore, the film deposition was performed with a deposition time of 20 hours. The results of varying the output of the second ion gun to 500mA, 700mA, 1000mA, and 1200mA are shown below.

[0041] [Table 5]

[0042] From the above, the film thickness on the inner surface was made to be about 40% (41%~45%) of the film thickness on the bottom surface, and by keeping the incidence angle to 30 degrees or less, ion energy could be efficiently supplied to the film, and as a result, stress could also be controlled. "Stress could also be controlled" means the following: Film thickness changes with distance from the deposition source and Cosθ. When the amount of ion irradiation is changed, the stress changes from tensile stress to compressive stress at zero ion irradiation. This is because the film is densified by ion irradiation. With IAD, the amount of ion irradiation can be changed as an independent parameter, so stress can be controlled by changing the amount of ion irradiation. This is the case for a plane (incidence angle 0°), and there are almost no examples for oblique incidence. Furthermore, it was found that the second ion gun had almost no effect on the bottom surface. On the inner surface, when the output current of the second ion gun was 1200 mA, excessive ion irradiation caused the stress to become too high, resulting in film delamination. Figure 12 shows SEM images of the surface of the film formed when the ion current of the second ion gun was 700 mA. (a) is an image of the bottom surface, and (b) is an image of the inner surface. A dense film was obtained on both the bottom and inner surfaces.

[0043] <Example 2> The film was deposited in the same manner as in Example 1, except that the gas supplied to ion gun 1 was changed to "40 sccm of oxygen gas and 10 sccm of Ar gas". The results are shown in Table 6. Since the effect of ion irradiation can be understood by examining the film stress in Example 1, only film thickness and stress will be explained below. Adding Ar gas to the gas supplied to the first ion gun increased the stress on the film formed on the bottom surface. In other words, the ion irradiation efficiency improved. However, it did not significantly affect the film formed on the inner surface.

[0044] [Table 6]

[0045] <Example 3> The film was deposited in the same manner as in Example 1, except that the gas supplied to the second ion gun was changed to "40 sccm of oxygen gas and 10 sccm of Ar gas". The results are shown in Table 7. Adding Ar gas to the gas supplied to the second ion gun increased the stress on the film formed on the inner surface, thus improving the ion irradiation efficiency. However, this did not significantly affect the film formed on the bottom surface.

[0046] [Table 7]

[0047] Therefore, it is possible to independently control the parameters of the first and second ion guns. [Explanation of Symbols]

[0048] 12 Vacuum Chamber 15 (First) Ion Gun 16 Evaporation source 40 Ion Gun 41 SUS container 42 Plasma discharge chamber 43~45 electrode 46 RF coils 47 Cables for high-frequency application 48 Cables for applying high voltage 61 Base material 83 Base material holder 85 First axis of rotation 86 Second rotation support shaft 93. The second ion gun 94 Ion gun support stand 95 Anti-adhesion plate

Claims

1. A vacuum chamber in which the evaporation source and substrate are placed, An ion-assisted film deposition apparatus having a substrate holder for holding the substrate, A first rotating shaft that rotatably supports the substrate holder, The base material holder and the second rotation support shaft that rotatably supports the first rotation shaft, The first ion gun, The second ion gun, Equipped with, The aforementioned substrate holder rotates on its own axis and around its orbit (planetary rotation), The first axis of rotation is inclined with respect to the vertical, A portion of the substrate held by the substrate holder, the part that is relatively higher is designated as the higher portion, and the part that is relatively lower is designated as the lower portion. When the surface of the elevated portion is defined as follows: the surface substantially perpendicular to the axial direction of the first rotation axis is designated as the first surface, and the surface substantially parallel to the axial direction of the first rotation axis is designated as the second surface, The first ion gun is positioned below the higher part, The second ion gun is positioned below the lower part, The evaporation source is positioned between the first ion gun and the second ion gun. The first ion gun is positioned and orientation such that the angle of incidence of the upper portion of the ion beam irradiated from the first ion gun with respect to the first surface is 30° or less, and The ion-assisted film deposition apparatus is characterized in that the second ion gun is installed in a position and orientation such that the incident angle of the upper portion of the ion beam irradiated from the second ion gun with respect to the second surface is 30° or less.

2. The system further comprises an ion gun support stand for supporting the second ion gun, The ion-assisted film deposition apparatus according to claim 1, wherein the ion gun support base is capable of moving up and down in the vertical direction.

3. The evaporation source is located near the center and at the bottom of the vacuum chamber. The second ion gun is positioned above the evaporation source. The system further includes an anti-deposition plate positioned below the second ion gun and above the evaporation source, Two axes contained in the X-Y plane parallel to the bottom surface of the vacuum chamber, where they intersect perpendicularly, are defined as the X-axis and the Y-axis. Among the axes included in the X-Z plane that intersect the aforementioned X-Y plane perpendicularly, when the axis that intersects the aforementioned X-axis perpendicularly is defined as the Z-axis, The Z coordinate value of the center of the first ion gun and the Z coordinate value of the center of the evaporation source are approximately equal. On the aforementioned X-Z plane, When the line connecting the center point of the evaporation source and the lower portion closest to the axis of the second rotation support shaft is defined as the anti-deposition line, A portion of the protective plate, the part closest to the axis of the second rotation support shaft, Located on the aforementioned anti-attachment line or located closer to the axis of the second rotation support shaft than the aforementioned anti-attachment line, The ion-assisted film deposition apparatus according to claim 1 or 2, wherein the anti-adhesion plate is located on the second ion gun side with respect to the axis of the second rotation support shaft.

Images