JP3919942B2 - Electrostatic adsorption device and vacuum processing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrostatic chuck and a vacuum processing apparatus, and more particularly to a technique for vacuum processing a film-like substrate used when forming a semiconductor device, a magnetic element, a dielectric element, a wiring circuit, or the like.
[0002]
[Prior art]
In recent years, a film-like substrate such as polyimide has been used as a substrate material for manufacturing semiconductor devices, magnetic elements and the like.
[0003]
When manufacturing a semiconductor device or a magnetic element using such a film-like substrate, the etching apparatus is particularly important because thin film formation by sputtering or CVD and thin film patterning by etching are repeated. Is being viewed.
[0004]
A conventional one of such an etching apparatus will be described. Referring to FIG. 6A, reference numeral 101 denotes a conventional parallel plate type plasma etching apparatus. This plasma etching apparatus 101 has a processing chamber 102, a lower electrode 111 is provided on the inner bottom surface side, and an upper electrode 103 is insulated on the ceiling side of the processing chamber 102 above the lower electrode 111. It is provided via the object 105.
[0005]
The lower electrode 111 is connected to the ground potential via the wall surface, and the upper electrode 103 is connected to the high frequency power source 109 via the matching box 110.
[0006]
A vacuum pump 120 and a gas introduction system 121 are connected to the processing chamber 102. When etching is performed using the plasma etching apparatus 101, first, the vacuum pump 120 is activated to start processing chamber 102. The inside is evacuated to a high vacuum state in advance.
[0007]
Next, while maintaining a high vacuum state, a film-like substrate 106 made of polyimide or the like, which is to be etched, is carried into the processing chamber 102, placed on the lower electrode 111 and fixed, and a gas introduction system 121. Then, the valve 122 provided in the chamber is opened, and the etching gas is introduced into the processing chamber 102 from the gas introduction pipe 123.
[0008]
After the inside of the processing chamber 102 is stabilized at a predetermined pressure, when the high frequency power source 107 is started and a high frequency voltage of 13.56 MHz is applied to the upper electrode 103 via the matching box 110, an etching gas plasma is generated near the surface of the lower electrode 111. And the thin film on the surface of the substrate 106 is etched.
[0009]
Etching using such plasma has the advantages that pattern processing dimensional accuracy is improved compared to wet etching, the manufacturing process is simplified, and etching is uniform. is there.
[0010]
An electrostatic chuck is widely used as the lower electrode 111 on which the substrate 106 is placed and fixed by the plasma etching apparatus 101. Since the electrostatic chuck electrostatically attracts the substrate 106 to the surface, the electrostatic chuck has high adhesion to the substrate, and thus has an advantage of good controllability of the substrate temperature.
[0011]
This electrostatic chuck is configured by coating electrodes 130 and 131 for applying a voltage for electrostatic attraction with an insulator 132. The insulator 132 is completely covered with the electrodes 130 and 131. It is practically impossible to manufacture an electrostatic chuck corresponding to a large area of 300 mm or more, particularly 500 mm or more, because it is difficult to coat the film and it is difficult to make the thickness of the insulator 132 uniform. I could say that.
[0012]
Therefore, a technique has been considered in which a clamp is provided around the lower electrode 111 without using an electrostatic chuck to mechanically fix the substrate 106. In this case, when the temperature of the substrate 106 increases, As shown in FIG. 6B, the substrate 106 is lifted from the surface by about 5 to 6 mm, and the gap 130 is formed between the substrate 106 and the lower electrode 111.₁~ 130_FourThis gap 130 is generated.₁~ 130_FourIn other words, the discharge at the time of plasma generation is concentrated and the substrate 106 is burnt.
[0013]
[Problems to be solved by the invention]
The present invention was created in order to solve the problems of the conventional technology, and its purpose is to provide a technology suitable for performing plasma processing such as etching or film formation on a film-like substrate. There is to do.
[0014]
[Means for Solving the Problems]
  In order to solve the above-mentioned problems, the invention described in claim 1 is an electrostatic adsorption device for electrostatically adsorbing a processing object on a surface, and for electrostatic adsorption to which a voltage necessary for the electrostatic adsorption is applied. An electrode and an electrode support portion made of an insulating material that covers and supports the electrode for electrostatic attraction, and at least the electrode support portion is divided into a plurality of portions.The electrode support portions divided into a plurality are arranged such that a gap is provided between the electrode support portions adjacent to each other, and the gap is provided with a buffer material made of a material that can relieve stress, The buffer material is an electrostatic adsorption device made of an adhesive.
[0015]
  Invention of Claim 2 is the electrostatic attraction apparatus of Claim 1, Comprising:An electrostatic adsorption device for electrostatically adsorbing a processing object on the surface, covering and supporting the electrostatic adsorption electrode to which a voltage necessary for the electrostatic adsorption is applied, and the electrostatic adsorption electrode, An electrode support portion made of an insulator, and at least the electrode support portion is divided into a plurality, and the divided electrode support portions are provided with a gap between the electrode support portions adjacent to each other. The electrostatic attraction device is arranged and provided with a buffer material made of a material capable of relaxing stress in the gap.
[0016]
  The invention described in claim 3Either of Claim 1 or Claim 2The electrostatic attraction apparatus according to claim 1, wherein the gap is 1 mm or less.It is an electrostatic adsorption device.
  The invention according to claim 4Claims 1 toIt is an electrostatic attraction apparatus of any one of Claim 3, Comprising:The electrostatic chucking device is provided with a protective plate in the gap, at a position in the middle of the electrode support portion in the thickness direction and separating the gap in the vertical direction.
[0017]
  The invention according to claim 5 is the invention according to claims 1 toClaim 4The electrostatic attraction apparatus according to claim 1, wherein the plurality of divided electrode support portions are provided on a single mounting substrate.It is an electrostatic adsorption device.
  The invention described in claim 66. The electrostatic attraction apparatus according to claim 5, wherein each of the electrode support portions is fixed to the mounting substrate with an adhesive.
[0018]
A seventh aspect of the present invention is the electrostatic adsorption device according to any one of the first to sixth aspects, wherein two types of the electrostatic adsorption electrodes are provided, and the two types of electrostatic adsorption devices are provided. The configuration is such that a constant voltage is applied between the electrodes.
[0019]
The invention described in claim 8 is a vacuum processing apparatus, comprising a processing chamber capable of being evacuated, and the electrostatic adsorption apparatus described in any one of claims 1 to 7.
[0020]
The present invention is configured as described above, and the electrode support part that covers and supports the electrostatic chucking electrode is divided into a plurality of parts, and is arranged so that a gap is provided between adjacent electrode support parts.
[0021]
For this reason, by dividing the electrode support part until it can be formed with an insulating film that coats the electrode for electrostatic adsorption and can be manufactured with a uniform film thickness of the insulator, it can be processed. According to the size and shape of an object, an electrostatic chucking device capable of electrostatically chucking any substrate can be obtained.
[0022]
By doing so, the object to be treated can be electrostatically adsorbed on the surface of the electrostatic adsorption device, and the adhesion to the object to be treated is improved, so that the temperature controllability of the object to be treated is improved. In addition, since it is not necessary to fix the object to be processed using a clamp, it is possible to prevent the conventional problem that the object to be processed floats in such a case, and the object to be processed burns due to the concentration of discharge at the floating portion.
[0023]
Furthermore, by setting the gap to 1 mm or less, it is possible to suppress the floating of the processing object that slightly occurs even in electrostatic adsorption to the extent that there is no practical impact. This point will be described later with reference to FIG.
[0024]
In addition, since the buffer material is provided in the gap between the electrode support portions adjacent to each other, the stress caused by thermal expansion or thermal contraction can be relieved. Therefore, it is possible to prevent a microcrack from being generated on the surface of the electrode support portion due to the stress, and an abnormal discharge from the microcrack during the discharge during plasma generation.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
Referring to FIG. 1, reference numeral 1 denotes a plasma etching apparatus according to an embodiment of the present invention, which has a processing chamber 2. An electrostatic chuck 11 of the present embodiment is provided on the inner bottom surface side of the processing chamber 2.
[0026]
As shown in FIG. 2B, the electrostatic chuck 11 includes a support 12 (mounting substrate) made of a metal such as Al, a positive voltage application electrode 14A for applying a voltage necessary for electrostatic adsorption, and a negative voltage. The voltage application electrode 14B and the electrode support part 22 which is provided on the support 12 and covers and supports the positive voltage application electrode 14A and the negative voltage application electrode 14B.
[0027]
The electrode support portion 22 includes the insulating plate 13, the insulating sealing material 15, and the surface adsorption electrode 16. The insulating plate 13 is fixed on the support 12 with an adhesive 18, and is provided on the surface thereof with a positive voltage application electrode 14A and a negative voltage application electrode 14B which will be described in detail later. The insulating sealing material 15 is made of a relatively flexible resin, and is provided on the insulating plate 13 so as to cover the positive voltage applying electrode 14A and the negative voltage applying electrode 14B. Further, the surface adsorption electrode 16 is made of an insulating plate and is provided on the surface of the insulating sealing material 15.
[0028]
FIG. 2A shows the arrangement of the positive voltage application electrode 14A and the negative voltage application electrode 14B. In FIG. 2A, the insulating sealing material 15 and the surface adsorption electrode 16 formed on the positive voltage application electrode 14A and the negative voltage application electrode 14B are not shown in order to clearly show the arrangement relationship. .
[0029]
Both the positive voltage application electrode 14A and the negative voltage application electrode 14B are made of a metal material such as aluminum or copper formed in a comb shape. As shown in FIG. 2A, these are arranged on the insulating plate 13 so as to alternate between the positive voltage application electrode 14A and the negative voltage application electrode 14B, and adjacent positive voltage application electrode 14A and negative voltage application electrode 14B. Between the two electrodes (hereinafter referred to as the interelectrode distance). In this embodiment, the distance between the electrodes is 2 mm.
[0030]
The positive voltage application electrode 14A and the negative voltage application electrode 14B are connected to voltage application terminals 21A and 21B provided from the inside of the support 12 to the back surface through the insulating plate 13, respectively. These voltage application terminals 21A and 21B are connected to the positive voltage application electrode 14A and the negative voltage application electrode 14B, respectively. Are connected to the DC power supplies 8A and 8B through the matching box 4 provided in the adsorption voltage generator 8, and when the DC power supplies 8A and 8B are activated, the positive voltage application electrode 14A and the negative voltage application electrode 14B are connected. Each is configured to be able to apply positive and negative DC voltages.
[0031]
In the present embodiment, the above electrode support 22 is formed as shown in FIG.₁~ 22_FourAre divided into four, and adjacent electrode supports 22₁~ 22_FourA gap of 1 mm is provided between them. This gap is filled with a soft adhesive 19 having a rubber-like material.
[0032]
The electrode support 22 divided into four in this way₁~ 22_FourIs manufactured, the insulating plate 13 is bonded to the support 12 with the adhesive 18, and the positive voltage applying electrode 14A and the negative voltage applying electrode 14B are formed on the insulating plate 13, and then these are cut into four. To do. The electrodes 14A and 14B are also cut at the time of this cutting. After that, by joining the divided portions again with a conductive adhesive such as solder, a pattern as shown in FIG. 2A is secured. Yes.
[0033]
Further, the electrode support 22 divided into four parts is provided.₁~ 22_Four14A, the positive voltage application electrode 14A and the negative voltage application electrode 14B are all flush with each other on the insulating plate 13, and the distance between the positive voltage application electrode 14A and the negative voltage application electrode 14B and the surface of the surface adsorption electrode 16 is the same. Are all equal.
[0034]
As shown in FIG. 2B, a protective plate 17 is provided in the gap between the adjacent electrode supports 22. This protective plate 17 is provided for the purpose of preventing problems caused by the adhesive 19 evaporating and depleting due to heat or the like during cleaning of the plasma etching apparatus 1 and the plasma entering the electrodes near the gap. Yes.
A screw hole 20 is provided on the back surface of the support 12 and is screwed to the inner bottom surface of the plasma etching apparatus 1 shown in FIG.
[0035]
On the ceiling side of the processing chamber 2 above the electrostatic chuck 11 having such a configuration, an upper electrode 3 is provided via an insulator 5. The upper electrode 3 is connected to a high frequency power source 9 via a matching box 10 provided in the voltage generator 7. In addition, a vacuum pump 20 and a gas introduction system 21 are connected to the processing chamber 2.
[0036]
When plasma etching is performed using the plasma etching apparatus 1 having the above-described configuration, first, the vacuum pump 20 is activated to evacuate the processing chamber 2 to be in a high vacuum state in advance.
[0037]
Next, while maintaining a high vacuum state, a film-like substrate 6 (processing object) made of polyimide is carried into the processing chamber 2 and placed on the surface adsorption electrode 16 of the electrostatic chuck 11, and then a direct current power source. 8A and 8B are activated, and positive and negative DC voltages are applied to the positive voltage application electrode 14A and the negative voltage application electrode 14B, respectively, and a constant voltage in the range of 2 kV to 50 V is applied between these electrodes 14A and 14B. So that Then, an electrostatic adsorption force is generated between the substrate 6 and the surface adsorption electrode 16, and the substrate 6 is electrostatically adsorbed and fixed on the surface adsorption electrode 16.
[0038]
In the electrostatic chuck 11 of this embodiment, as shown in FIG. 3, the insulating sealing material 15 has a uniform thickness, and can be manufactured to the extent that the positive voltage application electrode 14A and the negative voltage application electrode 14B can be completely covered. The electrode support portion 22 has a certain size.₁~ 22_FourIs divided into four parts.
[0039]
For this reason, even when the substrate 6 is large, the electrostatic chuck 11 capable of electrostatic attraction with any size substrate 6 is obtained by dividing the electrode support portion 22 into a size that can be manufactured. be able to.
[0040]
Therefore, due to electrostatic adsorption, the adhesion between the substrate 6 and the electrostatic chuck 11 is improved, and the temperature controllability of the substrate 6 is improved. Moreover, since it is not necessary to fix the board | substrate 6 using a clamp like the past, the board | substrate 6 can be largely floated and it can prevent that the board | substrate 6 burns because discharge concentrates on the floated part.
[0041]
Further, even if the electrostatic chuck 11 undergoes thermal expansion or contraction and thermal stress is generated, first, such thermal stress is slightly relieved by the insulating sealing material 15, and the electrode support portion 22.₁~ 22_FourThe gap 19 is filled with an adhesive 19 made of a flexible material, which further reduces thermal stress. In particular, microcracks due to thermal stress are generated on the surface of the electrostatic chuck 11 to generate plasma. In this case, abnormal discharge can be prevented from occurring from the microcracks.
[0042]
After electrostatically adsorbing the substrate 6 on the electrostatic chuck 11 as described above, the substrate 6 is heated by a heater (not shown) to raise the temperature, the valve 22 provided in the gas introduction system 21 is opened, and the gas introduction tube is opened. An etching gas is introduced into the processing chamber 2 from 23.
[0043]
After that, after the inside of the processing chamber 2 is stabilized at a predetermined pressure, the high frequency power source 9 is activated, and a high frequency voltage having a frequency of 400 kHz is applied to the upper electrode 3 through the matching box 10. Then, plasma of an etching gas is generated in the vicinity of the surface of the electrostatic chuck 11 by discharge, and the surface of the substrate 6 is etched by this plasma.
[0044]
The inventors of the present invention measured various characteristics for the purpose of confirming the effect of the plasma etching apparatus 1 using the electrostatic chuck.
FIG. 4A shows the relationship between the bonding distance and the inter-electrode distance and the lift of the substrate when the substrate on the film is etched using the plasma etching apparatus 1 of the present embodiment.
[0045]
In FIG. 4A, the horizontal axis indicates the bonding distance and the inter-electrode distance. Here, the junction distance is a gap between the electrode support portions 22 adjacent to each other, and the inter-electrode distance is a pitch between the positive voltage application electrode 14A and the negative voltage application electrode 14B shown in FIG. Indicates. In FIG. 4A, the vertical axis indicates the amount of lifting, that is, how much the substrate 6 is lifted from the surface of the electrostatic chuck 11.
[0046]
In FIG. 4A, the curve (A) shows the relationship between the bonding distance and the lift, and the curve (B) shows the relationship between the distance between the electrodes and the lift.
Since it has been found that when the lift exceeds 1 mm, problems such as burning of the substrate have started to occur, it is desirable to suppress the lift to 1 mm or less. As shown in the curve (A), when the joining distance is 1 mm, the lift is 1 mm or less. However, when the joining distance exceeds about 1.2 mm, it is shown that the lift exceeds 1 mm. From this measurement result, it was confirmed that if the bonding distance was 1 mm or less, problems due to the floating of the substrate could be prevented.
[0047]
Further, from the curve (B), it can be seen that when the distance between the electrodes is 2 mm or less, the lift is suppressed to 1 mm or less, but when the distance exceeds 2 mm, the lift exceeds 1 mm. From this, it can be seen that the distance between the electrodes should be set to 2 mm or less in order to prevent problems due to the floating of the substrate.
[0048]
FIG. 4B shows the relationship between the discharge time and the substrate surface temperature for each of a plasma etching apparatus using an electrostatic chuck as in this embodiment and an etching apparatus not using an electrostatic chuck. Measurements were taken. In FIG. 4B, the horizontal axis represents the discharge time during plasma generation, and the vertical axis represents the substrate surface temperature.
[0049]
Here, for all measurements, 0.8 W / cm²Of high frequency power and CF as etching gas_FourAnd O₂Was introduced into the processing chamber at 500 SCCM, and the pressure in the processing chamber was 250 mTorr.
[0050]
Curve (C) in FIG. 4 (b) shows the measurement results when the frequency of the high frequency power is 350 kHz for the plasma etching apparatus not using the electrostatic chuck, and curve (D) does not use the electrostatic chuck. About a plasma etching apparatus, the measurement result in case the frequency of high frequency electric power is 13.56 MHz is shown. Curve (E) shows the measurement result when using the plasma etching apparatus of this embodiment using an electrostatic chuck.
[0051]
The curve (C) shows that the substrate surface temperature is 100 ° C. when the discharge time is 2 minutes, but reaches 200 ° C. when the discharge time becomes 8 minutes, and is 100 in just 6 minutes. It has been shown that a temperature rise of as much as ° C can be seen.
[0052]
In curve (D), although the change is not as rapid as in curve (C), the substrate surface temperature, which was 100 ° C. when the discharge time was 3 minutes, was changed to 200 ° C. when the discharge time was 15 minutes. It is shown that the temperature rises to 100 ° C. in 12 minutes.
[0053]
On the other hand, in the curve (E), the substrate surface temperature, which was 60 ° C. when the discharge time was 3 minutes, increased only to about 100 ° C. even when the discharge time was 20 minutes, and it was 17 minutes. The temperature rise is only about 40 ° C., and it can be seen that the substrate surface temperature does not fluctuate with respect to the discharge time compared to the plasma etching apparatus without electrostatic chuck shown in curves (C) and (D). It can be seen that the effect of the present invention that the temperature controllability is improved can be confirmed.
[0054]
FIGS. 5A and 5B show measurement results of the relationship between the high-frequency power and the polyimide etching rate when polyimide is etched using the electrostatic chuck of this embodiment.
[0055]
FIG. 5A shows the relationship between the high-frequency power and the etching rate when polyimide is etched by applying the electrostatic chuck of the present embodiment to each of the RIE apparatus and the plasma etching apparatus. In FIG. 5A, the horizontal axis represents high frequency power, and the vertical axis represents polyimide etching rate.
[0056]
In FIG. 5A, a curve (F) shows a measurement result when the electrostatic chuck is applied to an RIE apparatus, and a curve (G) shows a measurement result when the electrostatic chuck is applied to a plasma etching apparatus.
Here, CF is used as the etching gas for all measurements._FourAnd O₂Was introduced into the processing chamber at a flow rate of 500 SCCM, and the pressure in the processing chamber was 250 mTorr.
[0057]
Curve (F) shows that when the high frequency power is 1 kW, the etching rate is 4000 Å / min, and when the high frequency power is increased to 2 kW, the etching rate is improved to 8500 Å / min.
[0058]
Curve (G) shows that the etching rate is 2000 Å / min when the high frequency power is 1 kW, and the etching rate is increased to 4000 Å / min when the high frequency power is increased to 2 kW.
[0059]
From this measurement result, it can be seen that the RIE apparatus has a higher etching rate than the plasma etching apparatus at the same high-frequency power, and that the change amount of the etching rate with respect to the change amount of the high-frequency power is large.
[0060]
FIG. 5B shows the relationship between the high frequency power and the etching rate when the polyimide is etched using the etching apparatus equipped with the electrostatic chuck of the present embodiment. In FIG. 5B, the curve (H) shows the measurement result when the frequency of the high frequency power is 350 kHz, and the curve (I) shows the measurement result when the frequency of the high frequency power is 13.56 MHz.
[0061]
Here, CF is used as the etching gas for all measurements._FourAnd O₂Etching was performed by introducing the mixed gas with the gas at a flow rate of 500 SCCM into the processing chamber.
Curve (H) shows that the etching rate is 6000 kg / min when the high frequency power is 1 kW, and increases to 13500 kg / min when the high frequency power is 2 kW. It can be seen that min has increased.
[0062]
Curve (I) shows that the etching rate is 4000 kg / min when the high frequency power is 1 kW, and 8500 kg / min when the high frequency power is 2 kW. When the high frequency power is increased by 1 kW, the etching rate is 4500 kg. It can be seen that there is an increase in / min.
[0063]
From this, it can be seen that the curve (H) where the frequency of the high frequency power is small has a larger variation in the etching rate due to the change of the high frequency power and the etching rate is larger than the curve (I) where the frequency is high. .
[0064]
As described above, in the RIE apparatus, the etching rate is higher than that in the plasma etching apparatus, and the etching rate is increased by changing the high frequency power. Therefore, the RIE apparatus is preferable for high-speed etching. It seems to be
[0065]
However, in the RIE apparatus, it is necessary to apply a high-frequency voltage to the electrode on which the substrate is placed, and it is necessary to attach a transport mechanism for transporting the substrate to the electrode to which the high-frequency voltage is applied. For this reason, since it is necessary to insulate the transfer mechanism from the high-frequency voltage applied to the substrate, there is a technical problem that a substrate having a high degree of freedom such as a film-like substrate is technically difficult.
[0066]
In this regard, since the plasma etching apparatus is connected to the ground potential on the substrate side, it is not necessary to insulate from such a high frequency voltage, and an in-line etching apparatus, a double-sided etching apparatus, and a multistage electrode etching apparatus can be easily configured, Furthermore, there is an advantage that the manufacturing cost can be reduced to about 2/3. Therefore, although it is possible to apply the present invention to an RIE apparatus, it is preferable to apply it to a plasma etching apparatus rather than an RIE apparatus in practice.
[0067]
In the present embodiment, the plasma etching apparatus 1 is described as a vacuum processing apparatus. However, the present invention is not limited to this, and the present invention can also be applied to a film forming apparatus such as a CVD apparatus and other apparatuses such as a sputtering apparatus. It is.
[0068]
Further, in the electrostatic chuck 11 of the present embodiment, a bipolar type is adopted as an electrode for voltage application and is arranged as shown in FIG. 2A. However, the present invention is not limited to such an arrangement relationship, A monopolar type may also be used.
[0069]
Further, the electrode support 22 on the support 12.₁~ 22_FourHowever, the present invention is not limited to this, and may be divided into any number according to the size of the substrate.
Furthermore, in this embodiment, the electrode support part 22 is used.₁~ 22_FourHowever, the present invention is not limited to this, and if it is set to 1 mm or less, the floating of the substrate 6 can be suppressed. Further, although the interval between the positive voltage application electrode 14A and the negative voltage application electrode 14B is 2 mm, the present invention is not limited to this value and may be set to 2 mm or less.
[0070]
In the present embodiment, the frequency of the high-frequency voltage applied to the upper electrode 3 for plasma excitation is set to 400 kHz. However, the present invention is not limited to this, and is preferably set in the range of 150 kHz to 450 kHz. This is because the etching rate is substantially determined by the product of the plasma density and the ion energy, but by taking the above range, the etching rate is almost maximized and high-speed etching can be performed.
[0071]
Furthermore, in the present embodiment, a film-like substrate has been described as the object to be processed, but the present invention is not limited to this, and can be applied to other electrostatically attractable substrates such as a silicon substrate.
[0072]
【The invention's effect】
As described above, according to the present invention, even when the area of the processing object is large, it can be electrostatically adsorbed. Therefore, the temperature controllability of the substrate is improved, and there is no need to fix the substrate using a clamp. In such a case, the substrate is floated, and the conventional problem that the substrate is burnt due to concentration of discharge at the floating portion is prevented. it can.
[0073]
Furthermore, since microcracks do not occur even when thermal stress occurs in the electrostatic chuck, it is possible to prevent abnormal discharge from occurring from the microcracks.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view illustrating a plasma etching apparatus according to an embodiment of the present invention.
FIG. 2A is a diagram for explaining an arrangement relationship of electrodes in the electrostatic chuck according to the embodiment of the present invention.
(b): Cross-sectional view illustrating the configuration of the electrostatic chuck according to the embodiment of the present invention.
FIG. 3 is a plan view illustrating an electrostatic chuck according to an embodiment of the present invention.
FIG. 4A is a graph for explaining the relationship between the bonding distance and the inter-electrode distance and the lift of the substrate in the electrostatic chuck according to the embodiment of the present invention.
(b): a graph for explaining the relationship between the discharge time and the substrate surface temperature in the embodiment of the present invention
FIG. 5A is a graph comparing the relationship between high-frequency power and polyimide etching rate for an RIE apparatus and a plasma etching apparatus.
(b): A graph for explaining the relationship between high frequency power and polyimide etching rate when high frequency power having different frequencies is applied in the plasma etching apparatus of the embodiment of the present invention.
6A is a diagram for explaining the structure of a conventional RIE apparatus; FIG.
(b): Cross-sectional view for explaining the floating of a conventional film-like substrate
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Plasma etching apparatus 2 ... Processing chamber 3 ... Upper electrode 4 ... Gas introduction path 6 ... Substrate (object to be processed) 7 ... Voltage application part 8 ... Adsorption voltage generation part 11 ... Electrostatic chuck 12 ... Support body 13 ... Insulating plate DESCRIPTION OF SYMBOLS 14A ... Positive voltage application electrode 14B ... Negative voltage application electrode 15 ... Insulation sealing material 16 ... Surface adsorption electrode 19 ... Adhesive (buffer material) 22, 22₁~ 22_Four... Electrode support

Claims (8)

An electrostatic adsorption device for electrostatically adsorbing a processing object on a surface,
An electrode for electrostatic adsorption to which a voltage necessary for the electrostatic adsorption is applied;
Covering and supporting the electrode for electrostatic attraction, and having an electrode support portion made of an insulator,
At least the electrode support is divided into a plurality of parts ,
The electrode support parts divided into a plurality are arranged so that a gap is provided between the electrode support parts adjacent to each other,
The gap is provided with a cushioning material made of a material that can relieve stress,
The buffer material is an electrostatic adsorption device made of an adhesive . An electrostatic adsorption device for electrostatically adsorbing a processing object on a surface,
An electrode for electrostatic adsorption to which a voltage necessary for the electrostatic adsorption is applied;
Covering and supporting the electrode for electrostatic attraction, and having an electrode support portion made of an insulator,
At least the electrode support is divided into a plurality of parts,
The electrode support parts divided into a plurality are arranged so that a gap is provided between the electrode support parts adjacent to each other,
An electrostatic attraction apparatus provided with a buffer material made of a material capable of relaxing stress in the gap . The electrostatic attraction apparatus according to claim 1 , wherein the gap is 1 mm or less. The electrostatic according to any one of claims 1 to 3 , wherein a protective plate is provided in the gap at a position in the middle of the electrode support portion in the thickness direction and separating the gap in the vertical direction. Adsorption device. It said plurality of divided electrodes support portion, one electrostatic chuck according to any one of claims 1 to 4, characterized in that provided mounting substrate. The electrostatic attraction apparatus according to claim 5, wherein each of the electrode support portions is fixed to the mounting substrate with an adhesive.   7. The electrostatic adsorption electrode according to claim 1, wherein two types of electrostatic adsorption electrodes are provided, and a constant voltage is applied between the two types of electrostatic adsorption electrodes. The electrostatic attraction apparatus according to item. A processing chamber that can be evacuated;
A vacuum processing apparatus comprising: the electrostatic attraction apparatus according to claim 1.

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