JP4245868B2 - Method for reusing substrate mounting member, substrate mounting member and substrate processing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention provides a substrate processing apparatus for performing processing such as dry etching and film formation on a substrate such as a semiconductor wafer, a base member, an electrostatic chuck for substrate adsorption provided thereon, The present invention relates to a method for reusing a substrate mounting member having a base member and an organic adhesive that bonds the electrostatic chuck , such a substrate mounting member, and a substrate processing apparatus using the same .
[0002]
[Prior art]
In a manufacturing process of a semiconductor device or the like, processing under a high vacuum such as plasma etching is frequently used. Under such a high vacuum, vacuum suction cannot be used for holding a semiconductor wafer (hereinafter simply referred to as a wafer). For this reason, a mechanical clamp method for mechanically holding a wafer has been used. However, when holding a semiconductor wafer, it is necessary to bring the tip of the clamp into contact with the surface to be processed. In such a case, dust generation, contamination of the wafer surface, and the like occurred.
[0003]
In recent years, electrostatic chucks have been widely used to solve such problems. An electrostatic chuck is one in which an electrode is embedded in a highly insulating member such as a ceramic material, and a wafer is adsorbed by an electrostatic force such as a Coulomb force generated by applying a DC voltage to the electrode.
[0004]
Such an electrostatic chuck is bonded to a base member made of aluminum or the like by an adhesive, and a wafer mounting member is configured by the electrostatic chuck, the base member, and an adhesive that bonds them.
[0005]
When such a wafer mounting member is used in an environment using a highly corrosive process gas such as a plasma etching apparatus, the adhesive is eroded by the process gas, and the life of the mounting member is eroded by the adhesive erosion. However, the mounting member is replaced within a relatively short period of time, and the mounting member that has reached the end of its life is discarded.
[0006]
[Problems to be solved by the invention]
By the way, recently, since the size of the wafer has become as large as 300 mm, and the electrostatic chuck has also increased in size, the wafer mounting member including the electrostatic chuck has become expensive. Discarding expensive members within a relatively short period of time significantly increases member costs. There is also a problem that the amount of waste increases.
[0007]
The present invention was made in view of such circumstances, and reused without discarding the substrate placement member, a method of recycling a substrate mounting member such does not cause inconvenience as described above, such a substrate mounting It is an object of the present invention to provide a placement member and a substrate processing apparatus using such a placement member .
[0008]
[Means for Solving the Problems]
Since the electrostatic chuck is firmly bonded to a base member such as aluminum with an organic adhesive, conventionally , the substrate mounting member including the base member is removed from the substrate processing apparatus, and the base member and the electrostatic chuck are left intact. There was no idea of separating them from each other, and therefore it was impossible to reuse them. On the other hand, the present inventor can remove the organic adhesive without damaging the base member and the electrostatic chuck, and can separate them from each other. They found that they can be separated and reused when they are exchanged.
[0009]
The present invention has been completed on the basis of such knowledge, the substrate is placed in a substrate processing apparatus for processing a substrate, a base member, an electrostatic chuck for substrate adsorption provided thereon, A method of reusing a substrate mounting member having the base member and an organic adhesive layer for adhering the electrostatic chuck, wherein the base mounting member is replaced when the substrate mounting member is replaced with a new substrate mounting member. Removing the substrate mounting member including a member from the substrate processing apparatus, removing the organic adhesive layer to separate the base member and the electrostatic chuck, the base member and / or the static possess a step of reusing the chuck, wherein the substrate mounting member includes a feeding part provided to penetrate the base member, and a feeder line is inserted and fixed to the feeding portion extending from said electrostatic chuck Have The power supply portion is filled with a conductive resin from the back side of the base member to fix the power supply line, and the step of separating the base member and the electrostatic chuck includes the step of separating the organic adhesive layer. After removing, the base member and the electrostatic chuck are separated by separating the power supply portion and the power supply line by pushing the conductive resin from the back surface side of the base member with a press jig. Provided is a method for reusing a substrate mounting member.
[0010]
In the recycling method, hand press is preferred as the flop-less jig.
Furthermore, the organic adhesive layer is preferably removed with a resin removal solvent. Thus, by using the resin removal solvent, only the organic adhesive layer can be selectively removed, and these can be separated without damaging the base member and the electrostatic chuck. The organic adhesive layer can be composed of a silicon-based adhesive, and as the resin removal solvent, one containing n-octane / n-dodecylbenzenesulfonic acid can be used. The organic adhesive layer can be peeled off.
[0011]
According to another aspect of the present invention, a substrate is placed in a substrate processing apparatus for processing a substrate, and a base member, an electrostatic chuck for attracting a substrate provided thereon, and the base member and the electrostatic chuck are bonded. A substrate mounting member having an organic adhesive layer, comprising: a power feeding portion provided penetrating through the base member; and a power feeding line inserted and fixed to the power feeding portion and extending from the electrostatic chuck, The power supply unit is filled with conductive resin from the back side of the base member and the power supply line is fixed. When the power supply unit is replaced with a new one, the whole including the base member is removed from the substrate processing apparatus. the after removing the organic adhesive layer, the electrostatic and the base member and separating the feed line and the feed portion by forcing the conductive resin by the press jig from the back side of the base member Separating the jack, the base member and / or the electrostatic chuck to provide a substrate mounting member, characterized be reused.
[0013]
Furthermore, the present invention provides a substrate processing apparatus for processing a substrate in a state where the substrate is mounted on the substrate mounting member, wherein the substrate mounting member has the above-described configuration. To do.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view showing a plasma etching apparatus equipped with a wafer mounting member that is a substrate mounting member to which the recycling method of the present invention is applied. The plasma etching apparatus 1 is configured as a capacitively coupled parallel plate etching apparatus in which electrode plates are opposed in parallel in the vertical direction, and a plasma forming power source is connected to one of them.
[0015]
The plasma etching apparatus 1 has a cylindrical chamber 2 made of, for example, aluminum whose surface is ceramic sprayed, and the chamber 2 is grounded for safety. A support member 5 made of an insulating material is provided at the bottom of the chamber 2, and an RF plate 4 is provided on the support member 5 via a seal ring 6. A wafer W is placed on the RF plate 4. A wafer mounting member 3 is provided. A space formed between the support member 5 and the RF plate 4 by the seal ring 6 is evacuated to form a vacuum heat insulating layer 7.
[0016]
The wafer mounting member 3 includes a base member 8 made of aluminum and having an upper central portion formed into a convex disk shape, an electrostatic chuck 9 provided on the base member 8, and a base member 8. And an organic adhesive layer 10 for adhering the electrostatic chuck 9 to each other.
[0017]
A refrigerant chamber 11 is provided inside the base member 8. A refrigerant such as Galden is introduced into the refrigerant chamber 11, and the cold heat is transferred to the wafer via the organic adhesive layer 10 and the electrostatic chuck 9. Heat is transferred to W, whereby the processing surface of the wafer W is controlled to a desired temperature. Three wafer lifting pins 12 (only two are shown) for raising and lowering the wafer W through the base member 8, the organic adhesive layer 10, and the electrostatic chuck 9 protrude and retract from the upper surface of the electrostatic chuck 9. It is provided as possible. These wafer elevating pins 12 are supported by a support plate 13, and this support plate 13 is moved up and down in a space 15 provided in the lower center of the base member 8 by a cylinder 14, so that the wafer elevating pins 12 are raised and lowered. It has become.
[0018]
The electrostatic chuck 9 is configured by embedding an electrode 17 inside a main body 16 made of an insulating ceramic, and a power supply line 18 made of a Cu stranded wire is connected to the electrode 17 by solder or the like. In addition, a power feeding portion 19 is provided inside the base member 8 so as to penetrate the organic adhesive layer 10 from the bottom thereof to the lower surface of the electrostatic chuck 9. The power feeding portion 19 is made of aluminum, and the lower portion thereof has a flange shape and has a through-hole penetrating vertically. The power feeding portion 19 and the base member 8 are insulated by an insulating resin 20. A power supply line 18 of the electrode 17 is inserted into the through hole of the power supply unit 19 from above, and in this state, the through hole is filled with a conductive resin 21. Therefore, the power supply line 18 is fixed by the conductive resin 21 in the through hole. A power supply line 22 extending downward is connected to the conductive resin 21, and this power supply line 22 extends from a high-voltage DC power supply 23, and a DC voltage is applied from the DC power supply 23 to the electrode 17 of the electrostatic chuck 9. As a result, the wafer is electrostatically attracted by electrostatic force, for example, Coulomb force.
[0019]
The RF plate 4 is made of aluminum, and a power feed rod 24 is connected thereto. A matcher 25 is connected to the tip of the power feed rod 24, and an RF power source 26 is connected to the matcher 25. A high frequency power having a predetermined frequency is applied from the RF power source 26 to the wafer mounting member 3 through the RF plate 4. The wafer mounting member 3 functions as a lower electrode.
[0020]
Gas supply passages 27a and 27b for supplying heat transfer gas, for example, He gas, are provided at the end and the center of the back surface of the wafer W through the support member 5, the RF plate 4, and the wafer mounting member 3, respectively. These are connected to the gas supply mechanism 28, and the heat transfer gas is supplied from the gas supply mechanism 28 to the entire back surface of the wafer W through the gas supply paths 27a and 27b, whereby the chamber 2 is exhausted. Even if kept in a vacuum, the wafer W can be effectively cooled by the refrigerant in the refrigerant chamber 11.
[0021]
Above the wafer mounting member 3, a shower head 30 that functions as an upper electrode is provided in parallel with the wafer mounting member 3. The shower head 30 is supported on the top wall of the chamber 2 via an insulating material 31, and the shower plate 32 facing the wafer mounting member 3 has a number of gas discharge holes 33.
[0022]
A gas inlet 34 is provided at the upper center of the shower head 30, and a gas supply pipe 35 is connected to the gas inlet 34. Further, an etching gas supply system 36 is connected to the gas supply pipe 35. Is connected. Then, a predetermined etching gas is supplied from the etching gas supply system 36. As the etching gas, a gas usually used in this field such as a halogen element-containing gas is used.
[0023]
An exhaust pipe 37 is connected to the bottom wall of the chamber 2, and an exhaust device 38 is connected to the exhaust pipe 37. The exhaust device 38 includes a vacuum pump such as a turbo molecular pump, and is configured so that the chamber 2 can be evacuated to a predetermined reduced pressure atmosphere, for example, a predetermined pressure of 1 Pa or less. A wafer loading / unloading port 39 is provided on the side wall of the chamber 2, and the wafer loading / unloading port 39 can be opened and closed by a gate valve 40. Then, the wafer W is transferred between the adjacent load lock chamber (not shown) via the wafer loading / unloading port 39 with the gate valve 40 opened.
[0024]
A power feeding rod 41 is connected to the shower head 30 that functions as an upper electrode. A matcher 42 is connected to the tip of the power feed rod 41, and an RF power source 43 is connected to the matcher 42. From the RF power source 43, for example, high frequency power having a frequency of 60 MHz is supplied. Further, a low pass filter (LPF) 44 is connected to the shower head 30.
[0025]
The above-described RF power source 26 connected to the RF plate 4 has a frequency of 2 MHz, for example, and functions as an RF power source for ion attraction. Note that a high-pass filter (HPF) 45 is connected to the RF plate 4.
[0026]
Therefore, a high frequency electric field is formed in the space between the wafer mounting member 3 functioning as the lower electrode and the shower head 30 by the high frequency power applied to the shower head 30 from the RF power source 43, and plasma of etching gas is formed. At the same time, ions are attracted to the wafer W by the high-frequency power applied to the wafer mounting member 3 from the RF power source 26, and the wafer W can be efficiently plasma-etched.
[0027]
Next, a processing operation in the plasma etching apparatus configured as described above will be described.
First, the gate valve 40 is opened, the wafer W is loaded into the chamber 2 through a wafer loading / unloading port 39 by a wafer conveyance mechanism (not shown), and is loaded on the electrostatic chuck 9 of the wafer loading member 3. After closing 40, the inside of the chamber 2 is exhausted by the exhaust device 38 through the exhaust pipe 37.
[0028]
After the inside of the chamber 2 reaches a predetermined degree of vacuum, a predetermined etching gas is introduced into the chamber 2 from the etching gas supply system 36 at a predetermined flow rate, and a DC voltage is applied from the DC power source 23 to the electrode 17 so that the wafer is exposed. W is electrostatically adsorbed by the electrostatic chuck 9.
[0029]
In this state, a high frequency power having a predetermined frequency is applied from the RF power source 43 to the shower head 30, whereby a high frequency electric field is generated between the shower head 30 as the upper electrode and the wafer mounting member 3 as the lower electrode. The etching gas is turned into plasma, and a predetermined film on the wafer W is etched by this plasma. At this time, RF power of a predetermined frequency is applied from the RF power source 26 to the wafer mounting member 3 as the lower electrode so that ions in the plasma are drawn to the wafer mounting member 3 side, thereby improving the etching efficiency.
[0030]
In this case, the refrigerant is caused to flow through the refrigerant chamber 11 and the gas for heat transfer is supplied from the gas supply mechanism 28 to the entire back surface of the wafer W through the gas supply paths 27a and 27b. Thereby, the cooling heat of the coolant can be effectively transferred to the wafer W through the base member 8, the organic adhesive layer 10, the electrostatic chuck 9, and the heat transfer gas, and the temperature of the wafer W is set to a predetermined low temperature. A high etching rate can be secured by controlling.
[0031]
Since the etching as described above is performed by plasma of corrosive gas, when such an etching process is repeated many times, the organic adhesive layer 10 is eroded. As described above, an organic adhesive having a high thermal conductivity is selected so that the transmission of cold heat is effective as described above, and if such an organic adhesive layer is greatly eroded, sufficient heat is generated. Transmission is not performed, and temperature control of the wafer W becomes difficult. Therefore, when the organic adhesive layer 10 is eroded by a predetermined amount, the wafer mounting member 3 is replaced with a new wafer mounting member. The wafer mounting member 3 is also replaced when the electrostatic chuck 9 is damaged due to a sudden accident or the like. At this time, the used wafer mounting member 3 is conventionally discarded, but in the present embodiment, the used wafer mounting member 3 is reused in the following procedure.
[0032]
Hereinafter, the procedure will be described with reference to the flowchart of FIG. 2 and FIGS. First, when replacing the wafer mounting member 3 with a new substrate mounting member, the previous wafer mounting member 3 is removed from the plasma etching apparatus 1 (STEP 1).
[0033]
Subsequently, the organic adhesive layer is removed with a resin removing solvent (STEP 2). At this time, as shown in FIG. 3, the resin removing solvent 52 is stored in the bat 51, and the wafer mounting member 3 is placed so that the organic adhesive layer 10 is immersed in the resin removing solvent 52 therein. Place on bat 51. The bat 51 and the wafer mounting member 3 are covered with a sealing bag 53 in order to prevent the solvent from diffusing around. In this case, a silicon adhesive having good thermal conductivity is suitable as the organic adhesive, and when the organic adhesive layer 10 is composed of a silicon adhesive, n-octane / The organic adhesive layer 10 can be peeled and removed by using a mixed solvent containing n-dodecylbenzenesulfonic acid. In addition, as a silicon-type adhesive agent, the thing of a composition of mass: C: 24.2%, O: 40.0%, Al: 32.7%, Si: 12.1% is illustrated.
[0034]
After removing the organic adhesive layer 10 in this manner, the wafer mounting member 3 is as shown in FIG. That is, in the power supply unit 19, the power supply line 18 is fixed by the conductive resin 21 filled in the through hole of the power supply unit 19.
[0035]
As shown in FIG. 5, the wafer mounting member 3 from which the organic adhesive layer 10 has been removed is placed on a ceramic receiving tray 54 while being inverted upside down, and is pressed by a pressing jig, for example, a hand press 55. The conductive resin 21 filled in the through hole of the power feeding unit 19 is pushed in from above, and the power feeding line 18 attached to the electrode 17 of the electrostatic chuck 9 and the power feeding unit 19 are separated (STEP 3). Thereby, the base member 8 and the electrostatic chuck 9 are separated (STEP 4).
[0036]
Thereafter, as shown in FIG. 6, a new organic adhesive layer 10 'is formed on the separated base member 8, and a new electrostatic chuck 9' is mounted (STEP 5). Thereby, a new wafer mounting member 3 ′ that reuses the used base member 8 can be obtained. Of course, when the separated electrostatic chuck 9 is not damaged, the separated electrostatic chuck 9 may be mounted on the organic adhesive layer 10 ′ formed on the base member 8 as it is. In this case, both the base member 8 and the electrostatic chuck 9 can be reused. Further, the separated base member 8 and electrostatic chuck 9 may be stocked and reused as appropriate.
[0037]
Thus, the organic adhesive layer 10 can be removed without damaging the wafer mounting member 3, and the base member 8 and the electrostatic chuck 9 can be separated, and these can be reused. The expensive wafer mounting member 3 is not discarded, and the member cost can be significantly reduced. Moreover, since the wafer mounting member 3 is not basically discarded, the amount of waste can be reduced. Further, by reusing in this way, processing and the like can be omitted, so that the manufacturing time of the wafer mounting member 3 can be greatly shortened, leading to a shortened delivery time.
[0038]
The present invention can be variously modified without being limited to the above embodiment. For example, in the above-described embodiment, the present invention has been described with reference to an example in which the present invention is applied to a wafer mounting member used in a high frequency vertical application type parallel plate type etching apparatus. In addition, any substrate mounting member in which an electrostatic chuck is formed on the base member with an organic adhesive layer can be applied to other apparatuses such as a CVD film forming apparatus. Furthermore, in the above-described embodiment, the case where the present invention is applied to the substrate mounting member of the apparatus for processing a semiconductor wafer is illustrated. However, the present invention is not limited to this, and the substrate mounting member of the apparatus for processing another substrate such as an LCD substrate is used. It can also be applied .
[0039]
【The invention's effect】
As described above, according to the present invention, the substrate mounting member including the base member is removed from the substrate processing apparatus, and the organic adhesive between the base member of the substrate mounting member and the electrostatic chuck is removed. Since these are separated, at least one of them can be reused. Also, by removing the organic adhesive layer with a resin removal solvent, only the organic adhesive layer can be selectively removed, and these can be separated without damaging the base member and the electrostatic chuck. It becomes possible. As a result of the reusability of these, expensive substrate placement members are not discarded, and member costs can be significantly reduced. Further, since the substrate mounting member is not basically discarded, the amount of waste can be reduced. Further, by reusing in this way, processing and the like can be omitted, so that the manufacturing time of the substrate mounting member can be greatly shortened, leading to a shortened delivery time.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a plasma etching apparatus equipped with a wafer mounting member that is a substrate mounting member to which a recycling method of the present invention is applied.
FIG. 2 is a flowchart showing a procedure for reusing a wafer mounting member according to the embodiment.
FIG. 3 is a cross-sectional view showing a specific method for peeling and removing an organic adhesive layer of a wafer mounting member with a resin removal solvent.
FIG. 4 is a cross-sectional view showing the wafer mounting member after the organic adhesive layer is removed.
FIG. 5 is a cross-sectional view illustrating a method of separating a power feeding unit and a power feeding line of an electrostatic chuck by a hand press.
FIG. 6 is a cross-sectional view showing a state in which a new wafer mounting table is manufactured by reusing the base member of the wafer mounting table after separation.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1; Plasma etching apparatus 2; Chamber 3; Wafer mounting member (substrate mounting member)
8; base member 9; electrostatic chuck 10; organic adhesive layer 17; electrode 18; feeder 19; feeder 20; insulating resin 21; conductive resin 51; bat 52; Wafer (substrate)

Claims (5)

A substrate is placed in a substrate processing apparatus for processing a substrate, a base member, an electrostatic chuck for substrate adsorption provided thereon, and an organic adhesive layer for bonding the base member and the electrostatic chuck are provided. A method of reusing a substrate mounting member having
When replacing the substrate mounting member with a new substrate mounting member,
Removing the substrate mounting member including the base member from the substrate processing apparatus;
Removing the organic adhesive layer to separate the base member and the electrostatic chuck;
Reusing the base member and / or the electrostatic chuck;
I have a,
The substrate mounting member includes a power feeding portion provided through the base member, and a power feeding line that is inserted into and fixed to the power feeding portion and extends from the electrostatic chuck. The step of separating the base member and the electrostatic chuck is filled with conductive resin from the back side and the base member and the electrostatic chuck are separated, and then the back side of the base member is removed. A method of reusing a substrate mounting member, wherein the base member and the electrostatic chuck are separated by separating the power supply portion and the power supply line by pushing the conductive resin from a press jig . The method for reusing a substrate mounting member according to claim 1 , wherein the organic adhesive layer is removed by a resin removal solvent. The organic adhesive layer is composed of a silicon-based adhesive, and the resin removal solvent is a mixed solvent containing n-octane / n-dodecylbenzenesulfonic acid, and the adhesive layer is peeled off by the resin removal solvent. The method for reusing a substrate mounting member according to claim 2 , wherein the substrate mounting member is removed. A substrate is placed in a substrate processing apparatus for processing a substrate, a base member, an electrostatic chuck for substrate adsorption provided thereon, and an organic adhesive layer for bonding the base member and the electrostatic chuck are provided. A substrate mounting member having
The power supply unit provided through the base member and a power supply line inserted and fixed to the power supply unit and extending from the electrostatic chuck. Conductive resin is provided in the power supply unit from the back side of the base member. The feeder is filled and fixed,
When replacing with a new one, after removing the entire base member from the substrate processing apparatus and removing the organic adhesive layer, the conductive resin is removed by a pressing jig from the back side of the base member. The substrate mounting is characterized in that the base member and the electrostatic chuck are separated by separating the power feeding unit and the power feeding line by pushing, and the base member and / or the electrostatic chuck is reused. Element. A substrate processing apparatus for processing a substrate in a state where the substrate is mounted on a substrate mounting member,
The said substrate mounting member has the structure of Claim 4, The substrate processing apparatus characterized by the above-mentioned .

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