JPH0643176Y2 - In-line type film deposition system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to an in-line type film forming apparatus for forming a film on a sequentially transported substrate, and more specifically, an ion plating method, a vacuum evaporation method, a sputtering method, etc. The improvement of the in-line type film forming apparatus for forming a film on the substrate by the PVD method or the plasma CVD method.

[Prior Art] Among conventional in-line type film forming apparatuses, an in-line type ion plating apparatus will be described as an example. As an in-line type ion plating apparatus, as shown in a schematic sectional view in FIG. 7, a vacuum chamber 100 including a transfer section 101 for sequentially transferring a substrate P and a main body 103 communicating with the transfer section 101 and an opening 102. , An evaporation source 104 which is provided in the main body 103 so as to face the opening 102 and emits the thin film material M toward the substrate P.
Those equipped with are known. The inside of the vacuum chamber 100 is maintained at a vacuum by a vacuum pump (not shown). Opening
102 is partitioned by a shielding plate 105 between the transport unit 101 and the main body 103. As shown in FIG. 8 which is a sectional view taken along the line BB of FIG. 7, for example, the two evaporation sources 104 heat the thin film material M by electron beams (not shown), respectively, and the thin film material M is stored in the main body 103. Evaporate. The evaporation rate of the thin film material M is
Since the substrate P is transported in the transport unit 101, which is controlled to be constant via the crystal oscillation type film thickness monitor 106 provided on the back surface of the substrate 105 and the thin film material M is supplied from the opening 102, the substrate P is transported to the substrate P. A thin film is deposited. As described above, in the conventional in-line type ion plating apparatus, the transfer speed of the substrate P in the transfer unit 101 and the crystal oscillation type film thickness monitor 106.
The film thickness of the thin film formed on the substrate P is controlled by the evaporation rate of the thin film material M detected by.

Further, as another conventional in-line type ion plating apparatus, there is known one in which a shield plate for partitioning an opening has a predetermined shape in order to control the film thickness of a thin film of a substrate in a direction perpendicular to the transport direction. .

[Problems to be Solved by the Invention] The crystal oscillation type film thickness monitor used in the above-mentioned conventional ion plating apparatus generally has a large film thickness accuracy within about ± 5% because of a large fluctuation in the evaporation rate of the thin film material. Is the limit. In order to form an optical multi-layer film on a substrate, a film thickness accuracy of about ± 1% or less is required, so that it has been difficult to form the optical multi-layer film in the above conventional in-line type ion plating apparatus. Such a defect due to the low film thickness accuracy also exists in other in-line type film forming apparatuses such as the plasma CVD method.

The present invention has been made in view of the conventional problems described above, and an object thereof is to provide an in-line type film forming apparatus capable of forming a film with high film thickness accuracy.

[Means for Solving the Problems] The in-line type film forming apparatus of the present invention comprises: a transfer unit for sequentially transferring a substrate; a closed container including a main body communicating with the transfer unit through an opening; A discharge device which is provided facing the opening and discharges the thin film material toward the substrate, so that a thin film is formed on the surface of the substrate by the thin film material flying from the body through the opening. In the configured in-line film forming apparatus, the opening includes a main opening formed in the rear of the substrate in the transfer direction and a sub-opening formed in front of the main opening in the transfer direction. Is a film thickness monitor that detects a physical quantity corresponding to the film thickness of the substrate formed in the main opening, a movable shield plate that changes the opening area of the sub opening, and the movable film is detected by the film thickness monitor. It is characterized by having a drive unit for driving the shielding plate. It is a characteristic.

In the present invention, the film forming apparatus refers to an apparatus that is equipped with a closed container and a discharging device and forms a film on a substrate by a PVD method such as an ion plating method, a vacuum evaporation method, a sputtering method or a plasma CVD method. . The airtight container is composed of a transport unit for sequentially transporting substrates and a main body communicating with the transport unit through an opening. The discharging device is provided in the main body of the closed container so as to face the opening, and discharges the thin film material toward the substrate.
The film forming apparatus further includes a bias voltage applying unit,
A thin film is formed on the surface of the substrate by a thin film material that flies from the main body through the opening.

The features of the in-line type film forming apparatus of the present invention are the opening and the closed container.

The opening that connects the transfer unit of the closed container and the main body is composed of a main opening formed in the rear of the substrate in the transfer direction and a sub-opening formed in front of the main opening in the transfer direction. It is also possible to form a plurality of sub-openings.

The closed container has a film thickness monitor that detects a physical quantity corresponding to the film thickness of the substrate formed in the main opening, a movable shield plate that changes the opening area of the sub-opening, and a movable shield plate that is detected by the film thickness monitor. And a driving unit for driving. As the film thickness monitor, an optical film thickness monitor that detects spectral transmittance or spectral reflectance can be adopted. The number of movable shield plates may be one or more.

[Operation] In the in-line type film forming apparatus of the present invention, the substrate is sequentially transported by the transport unit, and the discharging device provided in the main body discharges the thin film material to the substrate of the transport unit through the main opening and the sub opening. If the film thickness (main set film thickness) to be formed by the main opening is set to be slightly smaller than the set film thickness, and the opening area of the main opening is determined from the substrate transport speed and the thin film material release speed. The thin film material flying through the main openings is deposited on the substrate surface, and a thin film having a thickness close to the main set thickness is formed on the substrate. At this time, it is considered that there is an error of about ± 5% between the main set film thickness and the actual film thickness. The film thickness monitor detects a physical quantity corresponding to the actual film thickness of the substrate formed in the main opening. The movable shield plate is driven by the drive unit by the detection of the film thickness monitor, and the deficiency (sub-set film thickness), which is the difference between the set film thickness and the actual film thickness, is formed by driving the drive unit. The opening area of the opening changes. Then, the thin film material is deposited on the surface of the substrate through the sub opening whose opening area has changed, and a thin film having a thickness close to the sub set thickness is formed. At this time, it is considered that there is an error of about ± 5% between the sub-set film thickness and the actual film thickness. However, in the in-line type film forming apparatus of the present invention, the sub-set film thickness is set by correcting an error of about ± 5% generated between the main set film thickness and the actual film thickness due to the main opening. Reduce the error between the film thickness and the final film thickness. If a plurality of sub-apertures are provided, the error can be corrected each time, and the film formation accuracy is further improved. Therefore,
With the in-line type film forming apparatus of the present invention, a thin film can be formed on the substrate with a film forming accuracy of about ± 1% or less of the set film thickness.

[Embodiment] An embodiment in which the present invention is embodied in an in-line type ion plating apparatus will be described below with reference to the drawings.

As shown schematically in FIG. 1, this ion plating apparatus has a vacuum chamber 1 as a closed container whose inside can be maintained at a vacuum by a vacuum pump (not shown), and a discharge for discharging a thin film material M toward a substrate P. Two evaporation sources 2 as a device
(See FIG. 2).

As shown in FIG. 1, the vacuum chamber 1 includes a transfer section 11 for sequentially transferring the substrates P and a main body formed below the transfer section 11.
It consists of 12 and. As shown in FIGS. 1 and 2, the transport unit 11 includes a manual shield plate 111, a fixed shield plate 112, and six movable shields in order from the rear side along the transport direction of the substrate P between itself and the main body 12. It has plates 113a-f. The manual shield plate 111 is guided on the main body 12 by a manual operation. The fixed shield plate 112 is fixed to the side wall of the transport unit 11. In addition, movable shield plate
Each of 113a to 113f is driven by a stepping motor 43 (see FIG. 3) and guided on the main body 12. Thus, the main opening 13a is provided between the manual shield plate 111 and the fixed shield plate 112.
And a sub-opening 13b is formed between the fixed shield plate 112 and the movable shield plates 113a to 113f. The transport unit 11 and the main body 12 communicate with each other through the main opening 13a and the sub opening 13b. The transport unit 11 includes a substrate holder (not shown) that transports the substrate P.

Further, this vacuum chamber 1 is provided with a transfer section 11 as shown in FIG.
An optical film thickness monitor 14 for detecting the spectral transmittance corresponding to the film thickness of the substrate P formed in the main opening 13a is provided between the upper surface of the substrate and the fixed shielding plate 112. This optical film thickness monitor 14 is fixed to the upper surface of the fixed shield plate 112 and emits light upward.
a to f (141b to f are not shown), and light receiving portions 142a to 142f that are fixed to the upper surface of the transport unit 11 and are formed on the substrate P and light receiving portions 142a to 142f that receive light transmitted through the substrate P.

Further, the vacuum chamber 1 is provided with a drive unit 4 that drives the movable shield plates 113a to 113f by the detection of the optical film thickness monitor 14. As shown in FIG. 3, the drive unit 4 includes a rack 41 fixed to the movable shield plate 113a, a pinion 42 meshing with the rack 41, and a rotary encoder having the pinion 42 as a rotation axis. It consists of a motor 43. The stepping motor 43 and the light receiving portion 142a of the optical film thickness monitor 14 are connected to the controller 5 having a CPU, a memory, an output I / F and an input I / F. The control device 5 includes a light receiving unit 14
The film thickness of the shortage of the substrate P is calculated from the spectral transmittance detected by 2a, and the movable shield plate 113a is driven by the amount corresponding to this shortage. The other movable shield plates 113b to 113f are also the optical film thickness monitor 14
The light receiving units 142b to 142f have the same configuration. Thus
The movable shield plates 113a to 113f are driven by the drive unit 4, and the auxiliary opening
The opening area of 13b changes. The drive unit 4 and the like are not shown in FIGS. 1 and 2.

As shown in FIG. 1, two evaporation sources 2 are provided in the center of the main body 12 so as to face the main opening 13a and the sub-opening 13b. The evaporation source 2 is the same as the conventional one equipped with an electron gun, and evaporates the thin film material M toward the substrate P.

The ion plating apparatus of this embodiment is the same as the vacuum chamber 1 described above.
In addition to the evaporation source 2, a DC bias voltage applying means (not shown) that applies a bias voltage to the substrate P, a high-frequency excitation coil (not shown) that ionizes the thin film material M evaporated from the evaporation source 2, and evaporation of the ionized thin film material M A crystal oscillation type film thickness monitor 3 for detecting the speed is provided. As shown in FIG. 1, the crystal oscillation type film thickness monitor 3 controls the electron gun of the evaporation source 2 through a film thickness controller (not shown) like the conventional one, and the lower surface of the fixed shield plate 112. It is fixed to.

Next, the operation of the ion plating apparatus of this embodiment will be described. First, as shown in FIG.
The set film thickness T of the thin film to be formed on the substrate P is determined, and the main set film thickness T ₁ is determined with 95% of this set film thickness T. In this ion plating apparatus, as shown in FIG. 5, after initial setting in S1, the set film thickness T, the main set film thickness T _1, and the transfer speed V at which the transfer unit 11 transfers the substrate P in S2. Is input by a keyboard (not shown). Then, the film formation is executed in S3, and the evaporation rate v at which the evaporation source 2 evaporates the thin film material M is input in the crystal oscillation type film thickness monitor 3 in S4. The opening area of the main opening 13a is determined by these, and the operator moves the manual shielding plate 111 shown in FIG. 1 to a predetermined position. In this way, this ion plating apparatus forms a thin film on the surface of the substrate P by the thin film material M flying from the main body 12 through the main opening 13a. In S5, the process waits until the substrate P is passing through the main opening 13a. In S6, from the rotary encoder such as the stepping motor 41 to the original position xo of the movable shield plate 113a or the like.
Is input, and a signal is input from the optical film thickness monitor 14 in S7. In S8, the thickness t ₁ is calculated from the spectral transmittance calculated by the signal from the monitor 14 by the main openings 13a, secondary setting the thickness T to be deposited from the set thickness T- thickness t ₁ in the sub-aperture 13b ₂ is calculated (see FIG. 4). Further, the target position x, such as movable blocking plate 113a is calculated from the sub-set thickness T ₂ in the S8.
In S9, forward and reverse pulses corresponding to | xo−x | are output to the stepping motor 41, etc., and in S10, the rotary encoder of the stepping motor 41, etc. is used to output the current position of the movable blocking plate 113a, etc.
x ₁ is input. In S11, the movable shielding plate 113a etc. is the current position x ₁
To the target position x. In this way, this ion plating apparatus forms a shortage of thin film on the surface of the substrate P by the thin film material M flying from the main body 12 through the sub-opening 13b. Then, in S12, it is determined whether or not the film formation of the predetermined number of substrates P is completed. If NO, the current position x _{1 is set} to the original position x _{0 in} S13, and the process returns to S3.

In this ion plating apparatus, since T ₁ = 0.95T, there is an error of ± 5% from the error of the crystal oscillation type film thickness monitor 3, etc., so that t ₁ = 0.95T _{1 to} 1.05T ₁ . Also, T
-T ₁ = T ₂ and ± 5 from the error of the optical film thickness monitor 14.
Assuming there is an error of
_{If 2} , then t ₂ = 0.95T _{2 to} 1.05T ₂ . From these t ₁
Calculating the upper and lower limits of + t ₂ = t, t _max = 1.00012
5T, t _min = 0.995125T. Therefore, t _max −t
There is a film thickness error of _min = 0.005T. That is, this ion plating device can control the film thickness with a film thickness accuracy of ± 0.5%, and can control the film thickness with a precision 10 times that of the conventional one.

In the above embodiment, the optical film thickness monitor is a transmissive type including the light projecting section 141a and the light receiving section 142a. However, as shown in FIG. 6, the light projecting section 143 and the light receiving section 142a are used. It is also possible to adopt a reflection type that includes the portion 144. In this case, the film thickness can be measured even when the substrate P is opaque.

In the film forming apparatus of the present invention, it is preferable to set the main set film thickness in the range of 80 to 95%, more preferably 90 to 95% of the set film thickness. This is because a film thickness accuracy of 5 to 10 times that of the conventional one can be obtained.

[Advantage of Device] As described in detail above, in the in-line film forming apparatus of the present invention, the film thickness monitor detects the physical quantity corresponding to the film thickness after film formation in the main opening, and the movable shield plate is detected by this detection. Since the opening area of the sub-opening is changed and the shortage of the set film thickness is formed in the sub-opening, film formation with high film thickness accuracy is possible. Therefore, by using the ion line type film forming apparatus of the present invention, it is easy to form an optical multilayer film.

[Brief description of drawings]

1 to 5 relate to an ion plating apparatus according to an embodiment of the present invention. FIG. 1 is a schematic sectional view, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. Partial sectional view and block diagram, FIG. 4 is an explanatory diagram, and FIG. 5 is a flowchart.
FIG. 6 is a sectional view showing a part of another embodiment. 7 and 8 relate to a conventional ion plating apparatus,
FIG. 7 is a schematic sectional view, and FIG. 8 is a sectional view taken along the line BB of FIG. P ... Substrate, M ... Thin film material 1 ... Vacuum chamber (closed container) 11 ... Transfer unit, 113 ... Movable shield plate 12 ... Main body, 13a ... Main opening 13b ... Sub opening, 14 ... Optical film thickness monitor 2 ... Evaporation source (release device) 4 ... Drive unit

Claims (1)

[Scope of utility model registration request] 1. A hermetically sealed container comprising a transport unit for sequentially transporting substrates, a main body communicating with the transport unit through an opening, and a thin film material provided in the main body so as to face the opening and facing the substrate. In the in-line type film forming apparatus configured to form a thin film on the surface of the substrate by the thin film material flying from the main body through the opening, The main opening is formed at the rear of the substrate in the transport direction, and the sub-opening is formed at the front of the main opening in the transport direction. The closed container is a film of the substrate formed at the main opening. A film thickness monitor for detecting a physical quantity corresponding to the thickness, a movable shield plate for varying the opening area of the sub-opening, and a drive unit for driving the movable shield plate by detection of the film thickness monitor are provided. In-line type film forming equipment.