JP4030361B2 - Electrostatic adsorption method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrostatic attracting apparatus that attracts and holds a substrate with electrostatic force in an apparatus that performs processing such as film formation on the substrate, and more particularly to an electrostatic attracting apparatus that attracts and holds an insulating substrate.
[0002]
[Prior art]
In general, in a semiconductor process, for example, an electrostatic chuck (electrostatic chuck) is used as means for controlling the temperature of a substrate.
In recent years, an electrostatic chucking device has been devised that sucks not only a semiconductor substrate such as a silicon wafer but also an insulating substrate.
[0003]
In the case of such an electrostatic adsorption device, the adsorption force of the substrate can increase the gradient force by forming an adsorption electrode with a fine pattern, but it is necessary to increase the electric field gradient in order to increase the gradient force. is there.
[0004]
[Problems to be solved by the invention]
However, in an insulating substrate in which a device pattern is not formed in this way, for example, bare glass, there is no problem in increasing the electric field, but an electric field is not applied to a substrate on which a device pattern such as a fine MOS is formed. It has been found that if the gradient is increased more than necessary, problems such as gate dielectric breakdown and changes in the gate voltage threshold occur.
[0005]
On the other hand, if the electric field is weakened, even if dielectric breakdown or the like can be avoided, the essential attraction force becomes weak, causing a problem that it cannot be put to practical use.
[0006]
An object of the present invention is to provide an electrostatic chucking method that can exert an effective chucking force without affecting a processing target region such as a device pattern on a substrate.
[0007]
[Means for Solving the Problems]
As a result of intensive efforts to achieve the above object, the inventors of the present invention can solve the above problem by making the electrode portions of the pair of adsorption electrodes provided in the dielectric substantially equal in area and wide. As a result, the present invention has been completed.
[0008]
In order to achieve the above object, an invention according to claim 1 is provided with a device main body in which a plurality of adsorption electrodes are provided in a dielectric, and the adsorption electrodes have a pair of electrode portions having substantially the same area. , adsorption region in said device body has a device region corresponding to the region where the device pattern is formed of the adsorption object, and a non-device region that corresponds to the region where the device pattern has not been formed in the suction object An electrostatic adsorption method for adsorbing an insulative adsorption object using an electrostatic adsorption apparatus, wherein a pair of electrodes larger than the width of the electrode portion in the non-device region is provided as the electrode portion of the adsorption electrode. By providing the wide electrode portion, the electric field gradient in the device region is made smaller than the electric field gradient in the non-device region .
According to a second aspect of the present invention, in the first aspect, the interval between the wide electrode portions in the device region is larger than 1 mm and smaller than 3 mm .
[0009]
In the present invention, since the plurality of adsorption electrodes provided in the dielectric have a pair of wide electrode portions, the electric field gradient does not increase more than necessary, and the pair of wide electrode portions Therefore, it is possible to ensure the necessary suction force.
[0010]
As a result, according to the present invention, it is possible to adsorb the adsorption object with an appropriate adsorption force while suppressing the influence on various device patterns formed on the adsorption object.
[0011]
In the present invention, the adsorption zone in the apparatus main body and a device region and a non-device region by Rukoto provided wider electrode portion of the suction electrode in the device region, in particular the spacing of the wide electrode portions in the device region, By making it larger than 1 mm and not more than 3 mm, it is possible to adsorb the adsorption object with a larger adsorption force while minimizing the influence on various device patterns formed on the adsorption object.
[0012]
Thus, according to the present invention, there is provided a vacuum processing apparatus capable of performing effective processing without exerting an influence on a processing target region such as a device pattern and exhibiting an effective adsorption force. can do.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, detailed description of the implementation of the embodiment of the present invention with reference to the drawings.
Figure 1 is a diagram showing an outline substantially configuration of a vacuum processing apparatus Ru used in the present invention.
As shown in FIG. 1, the vacuum processing apparatus 1 of this includes a vacuum processing chamber 2 connected to a vacuum exhaust system (not shown).
[0014]
A susceptor 3 is provided in the lower part of the vacuum processing tank 2, and an electrostatic chuck (electrostatic chucking device) 4 for sucking and holding a substrate (sucking target) 10 to be described later is provided on the susceptor 3. It is fixed.
[0015]
The electrostatic chuck 4 has an electrostatic chuck plate (device main body) 5 formed in a predetermined shape using, for example, a ceramic material that is a dielectric, and a pair of later-described electrostatic chuck plates 5 is disposed inside the electrostatic chuck plate 5. Bipolar adsorption electrodes 6 and 7 are provided.
[0016]
Here, the suction electrodes 6 and 7 are connected to a connection terminal (not shown) of the electrostatic chuck power supply 8 disposed outside the vacuum processing tank 2.
[0017]
2 is a perspective view showing the configuration of the main part of the electrostatic chuck of the reference example of the present invention and the substrate to be attracted, FIG. 3A is a plan view showing the configuration of the main part of the electrostatic chuck, FIG. ) Is an explanatory diagram showing a dimensional relationship of the electrode portion of the attracting electrode of the electrostatic chuck.
[0018]
As shown in FIG. 2, the electrostatic chuck 4 in the form of this reference example sucks, for example, a rectangular substrate 10 in which a plurality of device patterns (processing target regions) 12 are formed on a glass substrate 11. The electrostatic chuck plate 5 has the same shape as the substrate 10 and is slightly larger than the substrate 10.
[0019]
The adsorption electrodes 6 and 7 of this reference example have a pair of positive and negative wide electrode portions 61 and 71.
The wide electrode portions 61 and 71 are formed in an elongated rectangular shape, and a plurality of wide electrode portions 61 and 71 are provided at regular intervals along the longitudinal direction of the electrostatic chuck plate 5.
[0020]
Here, the width W of the wide electrode portions 61 and 71 is not particularly limited, but is preferably 2 mm or more from the viewpoint of avoiding the influence of the substrate 10 on the device pattern 12, and more preferably described later. The size of the suction electrodes 6 and 7 may be determined so as to be about ½ of the area of the device region 51 by separating the electrode portions 61 and 71 of the attracting electrodes 6 and 7 by the distance D.
[0021]
Although distance D of the wide electrode portions 61 and 71 is not particularly limited, from the viewpoint of avoiding the influence on the device pattern 12 of the substrate 10, has preferably be greater than 1 mm.
[0022]
And the wide electrode parts 61 and 71 are comprised so that each area may become substantially equal.
[0023]
In the case of this reference example , the area ratio of the wide electrode portions 61 and 71 is not particularly limited, but is preferably 4: 6 to 6: 4, more preferably, from the viewpoint of securing the attractive force. Is 5: 5.
[0024]
Further, the total area of the adsorption electrodes 6 and 7 is not particularly limited, but is preferably 70% or more of the total area of the device pattern 12 of the substrate 10 from the viewpoint of securing the adsorption force.
[0025]
Furthermore, the wide electrode portions 61 and 71 of the suction electrodes 6 and 7 are preferably arranged in a rotationally symmetrical shape, for example, so that the suction force is not biased when the substrate 10 is sucked.
[0026]
In a normal case, a protective layer is formed on the surfaces of the adsorption electrodes 6 and 7. In this case, the thickness of the protective layer is not particularly limited, but is preferably 500 μm or less, more preferably 5 to 100 μm, from the viewpoint of securing adsorption power.
[0027]
As described above, according to this reference example , since the plurality of adsorption electrodes 6 and 7 provided in the dielectric have the pair of wide electrode portions 61 and 71, the electric field gradient is larger than necessary. In addition, since the areas of the pair of wide electrode portions 61 and 71 are substantially equal, a necessary suction force can be ensured.
[0028]
As a result, according to this reference example , the substrate 10 can be adsorbed with an appropriate adsorbing force while suppressing the influence on the various device patterns 12 formed on the substrate 10.
[0029]
And according to this reference example , the vacuum processing which can perform a smooth process by exhibiting an effective adsorption force without affecting the processing target region such as the device pattern 12 of the substrate 10. A device 1 can be provided.
[0030]
FIG. 4 is a plan view showing the configuration of an electrode in another reference example of the present invention. Hereinafter, portions corresponding to those in the reference example are given the same reference numerals, and detailed description thereof is omitted.
[0031]
As shown in FIG. 4, in the case of this reference example , the wide electrode portions 61A and 71A of the adsorption electrodes 6 and 7 are formed in a nested shape.
[0032]
In the case of this reference example , the widths and intervals of the wide electrode portions 61A and 71A of the adsorption electrodes 6 and 7 are the same conditions as in the above reference example .
[0033]
According to this reference example having such a configuration, since the electrode portions 61A and 71A of the adsorption electrodes 6 and 7 are formed in a nested shape, the difference in adsorption force due to the presence of the positive and negative adsorption electrodes 6 and 7 Or there exists a merit that the difference of a residual adsorption | suction force can be averaged. Since other configurations and operational effects are the same as those in the above-described reference example , detailed description thereof will be omitted.
[0034]
FIG. 5 is a plan view showing a configuration of an electrode in still another reference example of the present invention. In the following, portions corresponding to those in the reference example are denoted by the same reference numerals, and detailed description thereof is omitted.
[0035]
As shown in FIG. 5, in the case of this reference example , it has the wide electrode part 61B formed in the ring shape, and the rectangular wide electrode part 71B formed inside this wide electrode part 61B.
[0036]
In the case of this reference example , the widths and intervals of the wide electrode portions 61B and 71B of the adsorption electrodes 6 and 7 are the same as those in the above reference example .
[0037]
According to this reference example having such a configuration, since the electrode structure is simple, there is an advantage that the manufacture is facilitated. Since other configurations and operational effects are the same as those in the above-described reference example , detailed description thereof will be omitted.
[0038]
6 (a) is a plan view showing a main configuration of an electrostatic chuck used in the implementation of the embodiment of the present invention, FIG. 6 (b) is a schematic diagram showing the structure of the electrostatic chuck electrode, In the following, portions corresponding to those in the above reference example are denoted by the same reference numerals, and detailed description thereof is omitted.
[0039]
FIG. 7A is an explanatory diagram showing the dimensional relationship of the wide electrode portion in the non-device region of the electrostatic chuck, and is an enlarged view of a portion A indicated by a one-dot chain line in FIG. (b) is explanatory drawing which shows the dimensional relationship of the wide electrode part in the device area | region of the electrostatic chuck.
[0040]
As shown in FIG. 6A, the electrostatic chuck 4C in the present embodiment includes an area 51 (hereinafter referred to as “device area”) 51 corresponding to the device pattern 12 of the substrate 10 and a device pattern 12 of the substrate 10. The electrostatic chuck plate 5C is divided into a region (hereinafter referred to as “non-device region”) 52 corresponding to a region that is not formed.
[0041]
As shown in FIG. 6B, the electrostatic chuck plate 5 in the present embodiment is configured such that the dense structures of the attracting electrodes 6 and 7 in the device region 51 and the non-device region 52 are different. . That is, the wide electrode portions 61C and 71C described above are formed in the device region 51 so that the electric field gradient in the device region 51 is smaller than the electric field gradient in the non-device region 52.
[0042]
In this case, the adsorption electrodes 6 and 7 are connected in series in the device region 51 and the non-device region 52, respectively, and the width W of the wide electrode portions 61C and 71C of the adsorption electrodes 6 and 7 in the device region 51 is non-device. It is formed to be larger than the width w of the electrode portions 62C and 72C in the region 52.
[0043]
As shown in FIGS. 7A and 7B, in the present invention, the width W of the wide electrode portions 61C and 71C in the device region 51 is not particularly limited. From the viewpoint of avoiding the influence on ten device patterns 12, the thickness is preferably 1 mm or more, and more preferably 1 to 3 mm.
[0044]
In addition, the width w of the electrode portions 62C and 72C in the non-device region 52 is not particularly limited, but is preferably 1 mm or less, more preferably 0.1 to 0.1 mm from the viewpoint of securing the adsorption force. 0.3 mm.
[0045]
On the other hand, the shapes of the wide electrode portions 61C and 71C in the device region 51 are not particularly limited. However, if the electrodes are formed in a rectangular shape as in the example shown in FIG. There is an advantage that it is easy to manufacture.
[0046]
On the other hand, the shapes of the electrode portions 62C and 72C in the non-device region 52 are not particularly limited, but if formed in a nested shape as in the example shown in FIG. There is.
[0047]
In the present embodiment, the gap D between the wide electrode portions 61C and 71C in the device region 51 is formed to be larger than the gap d between the electrode portions in the non-device region 52.
[0048]
In the present invention, the distance D between the wide electrode portions 61C and 71C in the device region 51 is not particularly limited, but is preferably larger than 1 mm from the viewpoint of avoiding the influence on the device pattern 12 of the substrate 10. More preferably, it is 1 to 3 mm.
[0049]
On the other hand, the distance d between the electrode portions 62C and 72C in the non-device region 52 is not particularly limited, but it is preferably 1 mm or less, more preferably 0.1 to 0.1 mm from the viewpoint of securing the attractive force. 0.3 mm.
[0050]
According to the present embodiment having such a configuration, since the electric field gradient in the device region 51 of the adsorption electrodes 6 and 7 is reduced, the influence on the device pattern 12 of the substrate 10 is minimized, and appropriate adsorption is performed. The substrate 10 can be adsorbed by force. Since other configurations and operational effects are the same as those in the above-described reference example , detailed description thereof will be omitted.
[0051]
FIG. 8 is a plan view showing a configuration of an electrode according to another embodiment of the present invention. In the following, portions corresponding to those of the above embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.
[0052]
As shown in FIG. 8, in the case of the present embodiment, in the device region 51 of the electrostatic chuck 4, the electrode portions 61 </ b> D and 71 </ b> D of the attracting electrodes 6 and 7 are formed in a nested shape.
[0053]
In the case of the present embodiment, the width and interval of the electrode portions 61D and 71D in the device region 51 are the same conditions as in the above embodiment.
[0054]
Further, the widths and intervals of the electrode portions 62D and 72D in the non-device region 52 are also the same conditions as in the above embodiment.
[0055]
According to the present embodiment having such a configuration, since the electrode portions 61D and 71D of the adsorption electrodes 6 and 7 are formed in a nested shape, the adsorption force due to the presence of the positive and negative adsorption electrodes 6 and 7 is reduced. There is an advantage that the difference or the difference in the residual adsorption force can be averaged. Since other configurations and operational effects are the same as those of the above-described embodiment, detailed description thereof is omitted.
[0056]
The present invention is not limited to the above-described embodiment, and various changes can be made.
For example, the shape, size, number, and the like of the wide electrode portion of the adsorption electrode are not limited to those of the above-described embodiments, and can be appropriately changed according to the processing target region of the substrate.
[0057]
Furthermore, the present invention can be applied to substrates on which various device patterns are formed, and the types of substrates can also be applied to various substrates.
[0058]
Furthermore, the present invention can be applied to various vacuum processing apparatuses including a sputtering apparatus and a CVD apparatus.
[0059]
【The invention's effect】
As described above, according to the present invention, it is possible to minimize the influence on a processing target region such as a device pattern on a substrate while securing a necessary suction force during electrostatic suction.
[Brief description of the drawings]
Perspective view illustrating an essential part of the substrate to adsorb the electrostatic chuck of the reference example of Overview Once the configuration diagram of a vacuum processing apparatus used in the invention, FIG 2 shows the present invention Figure 3 (a): the plan view showing a main configuration of an electrostatic chuck (b): a plan showing the arrangement of electrodes in another reference example of illustration the present invention; FIG showing the dimensional relationship of the electrode portion of the attraction electrode of the electrostatic chuck FIG plan view further showing the structure of electrodes in another reference example of the present invention; FIG 6 (a): a plan view showing a main configuration of an electrostatic chuck used in the implementation of the embodiment of the present invention ( b): Schematic diagram showing the configuration of the electrode of the electrostatic chuck . FIG. 7 (a): An explanatory diagram showing the dimensional relationship of the wide electrode portion in the non-device region of the electrostatic chuck, as shown in FIG. Enlarged view of portion A indicated by alternate long and short dash line (b): Dimensional relationship of wide electrode portion in device region of electrostatic chuck Plan view showing the arrangement of electrodes in another embodiment of the illustration 8 the invention showing a [EXPLANATION OF SYMBOLS]
DESCRIPTION OF SYMBOLS 1 ... Vacuum processing apparatus 2 ... Vacuum tank 4 ... Electrostatic chuck (electrostatic adsorption apparatus) 5 ... Electrostatic chuck plate (apparatus main body) 6, 7 ... Adsorption electrode 10 ... Substrate (adsorption object) 61, 71 ... Wide electrode Part

Claims (2)

An apparatus main body provided with a plurality of adsorption electrodes in a dielectric, the adsorption electrodes have a pair of electrode portions having substantially the same area, and an adsorption region in the apparatus main body forms a device pattern of an adsorption object Electrostatically attracting an insulating object to be attracted using an electrostatic attraction apparatus having a device region corresponding to the region formed and a non-device region corresponding to a region where the device pattern of the object to be attracted is not formed An adsorption method,
By providing a pair of wide electrode portions larger than the width of the electrode portion in the non-device region as the electrode portion of the adsorption electrode, the electric field gradient in the device region is greater than the electric field gradient in the non-device region. An electrostatic adsorption method that is made smaller. The electrostatic attraction method according to claim 1, wherein an interval between the wide electrode portions in the device region is greater than 1 mm and 3 mm or less.

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