KR100818761B1 - Electrode Intermediate Module for Anode Bonding Chamber and Anode Bonding Method Using the Same - Google Patents

Abstract

The present invention relates to an electrode intermediate module for an anode bonding chamber and a method of bonding anode using the same, in order to prevent contamination of the anode bonding chamber by sodium molecules during bonding of two heterogeneous wafers, the anode bonding chamber according to the present invention. The electrode intermediary module may include: an anode bonding chamber including an upper heater block and a lower heat block having a point pushing electrode disposed in a center thereof, the thermal medium block being formed in a disc shape having an empty center and having a high thermal conductivity; It is inserted into the space formed in the center of the thermal block is slidably moved, the center is formed in the shape of an empty disc, the center moving block is formed of a material having high thermal conductivity and the slide is inserted in the space formed in the center of the center moving block And an intermediate electrode electrically connected to the point pushing electrode and positioned between the upper heat block and the lower heat block.

Anode Junction, Electrode Separation, Washing, Annular Electrode

Description

An electrode mediation module for anodic bonding chamber and a method thereby

1 is a cross-sectional view of main parts of an anode bonding chamber according to the prior art.

FIG. 2 shows a state in which anode bonding is shown in FIG.

3 is an enlarged cross-sectional view of portion 'A' of FIG.

4 illustrates a state in which the anode bonding is completed in FIG. 1.

FIG. 5 is a plan view of the wafer anodically bonded by FIG.

6 is a sectional view of principal parts of an anode bonding chamber using an electrode intermediate module according to the first embodiment of the present invention.

FIG. 7 shows a state in which anode bonding is shown in FIG.

8 is a cross-sectional view of an electrode intermediate module according to a first embodiment of the present invention.

9 is a sectional view of principal parts of an anodic bonding chamber using an electrode intermediate module according to a second embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

10: anode bonding chamber 12: lower heater block

14: upper heater block 16: point pushing electrode

18: elastic member 20: glass wafer

21: depletion layer 22: SiO ₂ bonding layer

23: separation portion 24: silicon wafer

30: sodium particles 100,200: electrode parameters module

110,210: thermal parameter block 120,220: intermediate electrode

130,230: center moving block 225: annular intermediate electrode

235: annular moving block

The present invention relates to an electrode intermediate module for an anode bonding chamber and a method for bonding anode using the same, and more particularly, to a technique capable of preventing contamination of the anode bonding chamber by sodium molecules during bonding of two heterogeneous wafers. will be.

Anodic bonding is one of the methods of joining MEMS (Micro Electro Mechanical System) structures and is widely used for bonding heterogeneous materials.

Hereinafter, a cathode junction according to the prior art will be described with reference to the accompanying drawings.

1 is a cross-sectional view of an essential part of the anode bonding chamber according to the prior art, FIG. 2 shows a state in which the anode is being bonded in FIG. 1, FIG. 3 is an enlarged cross-sectional view of a portion 'A' in FIG. 2, and FIG. 4 is shown in FIG. Shows a state in which the anodic bonding is completed, and FIG. 5 is a plan view of the anodic bonded wafer by FIG.

As illustrated, the anode bonding chamber 10 according to the prior art includes a lower heater block 12 and an upper heater block 14, wherein the point pushing electrode 16 has an elastic member on the upper heater block 14. It is installed while being supported by 18.

An anode bonding process will be described below.

In a first step, the silicon wafer 24 and the glass wafer 20 are positioned on the lower heater block 12. The state at this time is shown in FIG.

In the second step, the upper heater block 14 is moved in the direction of the lower heater block 12. As a result, the upper heater block 14 is brought into contact with the glass wafer 20. In addition, the point pushing electrode 16 is in a state of pressing the center of the glass wafer 20 by the elastic force of the elastic member 18. The state at this time is shown in FIG.

In a third step, the upper heater block 14 and the lower heater block 12 are heated to heat the glass wafer 20 and the silicon wafer 24. The heating temperature at this time is set by the thermal expansion coefficient C _TE of the raw material (glass wafer, silicon wafer).

In a fourth step, a negative voltage is applied to the point pushing electrode 16 and a positive voltage is applied to the lower heater block 12. By applying a voltage, sodium cations contained in the glass wafer 20 move to the upper heater block 14, and oxygen anions move to the silicon wafer 24. The state at this time is shown in FIG.

Oxygen anions, which were included in the glass wafer 20, are transferred to the silicon wafer 24 by the application of voltage to bond with silicon to form the SiO ₂ bonding layer 22, thereby forming the depletion layer 21. On the other hand, such coupling proceeds in the circumferential direction from where the point pushing electrode 16 is located, thereby completing the coupling of the glass wafer 20 and the silicon wafer 24.

In a fifth step, the upper heater block 14 is returned to its original position. The state at this time is shown in FIG. As shown in FIG. 4, when the upper heater block 14 is in place, sodium particles 30 are attached to the upper heater block 14.

As such, when the sodium particles 30 are attached to the upper heater block 14, problems may occur during continuous anodic bonding, so the sodium particles 30 need to be removed. However, since the space between the upper heater block 14 and the lower heater block 12 is not large, since the cleaning is not easy, it takes a lot of maintenance and management time because the anode bonding chamber 10 must be disassembled and cleaned.

On the other hand, when the upper heater block 14 is in the original position and separated from the glass wafer 20, the point pushing electrode 16 and the glass wafer 20 formed of stainless steel or the like may adhere to each other, as shown in FIG. 5. Similarly, the surface damage portion 23 may occur on the glass wafer 20.

In addition, when the stainless steel is used as the electrode material, the voltage becomes poor when the DC voltage is applied and the current cannot be sufficiently applied.

The present invention has been made to solve the problems according to the prior art described above, and an object of the present invention is to provide an electrode-mediated module that is easy to clean even when sodium particles are attached.

Another object of the present invention is to prevent contamination inside the chamber as a result of the anode bonding process, and since only the electrode mediated module, which is a replaceable component, is contaminated and cleaned, it is easy to manage the process and equipment. It aims to provide.

It is still another object of the present invention to provide a method for anodic bonding with high yield since the point pushing electrode does not directly contact the glass wafer.

In addition, another object of the present invention is to provide an electrode intermediary module including an intermediary electrode capable of solving the problems of current shortage and voltage failure due to the use of stainless steel electrodes.

In order to achieve the above object, the electrode-mediated module for the anode bonding chamber according to the embodiment of the present invention is an anode bonding chamber comprising an upper heater block and a lower heat block in which a point pushing electrode is provided in the center, the center of which is empty. A thermal media block formed in a disk shape and formed of a material having high thermal conductivity; It is inserted into the space formed in the center of the thermal block is slidably moved, the center is formed in the shape of an empty disc, the center moving block is formed of a material having high thermal conductivity and the slide is inserted in the space formed in the center of the center moving block And an intermediate electrode electrically connected to the point pushing electrode and positioned between the upper heat block and the lower heat block.

Here, the thermal media block, the lower end of the inner diameter is further formed with a protruding end protruding toward the inside, the central moving block, the upper projection of the outer diameter is further formed protruding jaw is formed to the outside, the protruding It is preferable that the movement distance of the center moving block is limited by the step and the protruding jaw.

In addition, the heat medium block and the center moving block is preferably formed of a ceramic material.

In addition, the intermediate electrode is preferably formed of a graphite material.

On the other hand, the electrode mediating module for anodic bonding chamber according to the embodiment of the present invention further includes an annular mediating electrode and an annular moving block to which the annular mediating electrode is slidably movable, wherein the annular mediated electrode and the annular moving block It may be coupled concentrically with a central moving block coupled to the thermal media block.

In order to achieve the above object, the anode bonding method using the electrode intermediary module according to the embodiment of the present invention, in the method of anodic bonding the silicon wafer and the glass wafer in the anode bonding chamber, the silicon wafer and glass to the lower heater block Stacking wafers in sequence; A heat moving block formed in a disc shape having an empty center in the upper portion of the glass wafer, a center moving block having a shape of an empty center and movably coupled to a center empty space of the heat moving block, and a central bin of the center moving block; A second step of locating an electrode module including a medium electrode slidably coupled to a space; A third step of contacting the electrode parameter module and the upper heater block; A fourth step of heating the lower heater block and the upper heater block at different temperatures and applying a high voltage to the point pushing electrode of the upper heater block such that the thermal expansion rate of the silicon wafer is the same as that of the glass wafer; And a fifth step of anodic bonding the silicon wafer and the glass wafer by an intermediate electrode electrically connected to the point pushing electrode.

In the fourth step, it is preferable that the heating temperature of the upper heater block and the lower heater block is 180 to 450 ° C.

In the fifth step, the voltage applied to the point pushing electrode is preferably 200 to 1000V.

In the following, embodiments of the present invention are described with reference to the accompanying drawings.

In the following description of the present invention, if it is determined that detailed descriptions of related known functions or configurations may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In addition, the terms to be described later are terms set in consideration of functions in the present invention, and these terms may vary according to the intention or custom of the producer producing the product, and the definition of the terms should be made based on the contents throughout the present specification.

(First embodiment)

Hereinafter, an electrode intermediate module according to a first embodiment of the present invention will be described with reference to FIGS. 6 to 8.

FIG. 6 is a cross-sectional view of main parts of an anode bonding chamber using an electrode intermediate module according to a first embodiment of the present invention, FIG. 7 shows a state in which anode bonding is shown in FIG. 6, and FIG. 8 shows a first embodiment of the present invention. Is a cross-sectional view of the electrode intermediate module.

The electrode intermediary module 100 according to the first embodiment of the present invention is used between the upper heater block 14 and the lower heater block 12.

The electrode intermediary module 100 is configured to be slidably coupled to a central moving block 130 in which an intermediary electrode 120 is coupled to an empty space of the thermal intermediary block 110 formed in a disc shape having an empty center. . Here, the intermediate electrode 120 may be coupled to the center moving block 130 so as to be slidable, or may be fixed not to move.

On the other hand, the thermal block 110 and the central moving block 130 is formed of a ceramic material. As is well known to those skilled in the art, since the ceramic material has good thermal conductivity, the thermal media block 110 and the central moving block 130 can transfer heat generated by the upper heater block 14 to the glass wafer 20 well. have. In addition, the thermal medium block 110 is formed with a protruding end 112 protruding toward the inside of the lower portion of the inner diameter, and the central moving block 130 further includes a protruding jaw 132 protruding toward the outside of the central moving block 130. Is formed. In addition, it is preferable that a minute space is formed between the lower portion of the protruding end 112 and the upper portion of the protruding jaw 132 so that the Middle East moving block can slide.

In addition, the intermediate electrode 120 is formed of a graphite material. The graphite material is not only electrically conductive, but also easily separated after pressing the glass wafer 20 to prevent damage to the surface of the glass wafer 20.

(Anode bonding method)

Hereinafter, a method of anodic bonding using the electrode intermediate module according to the first embodiment described above will be described. Prior to the description, the present anode bonding method is described as an example of anodic bonding between a silicon wafer and a glass wafer, but it should be noted that the present invention is not particularly limited to the material of the wafer to be anodized.

In the first step, the silicon wafer 24 and the glass wafer 20 are sequentially stacked on the lower heater block 12.

In a second step, the electrode intermediate module 100 is positioned on the glass wafer 20. The state at this time is shown in FIG.

In a third step, the electrode intermediary module 100 and the upper heater block 14 are contacted. The state at this time is shown in FIG. As a result, the point pushing electrode 16 presses the intermediate electrode 120 according to the elastic force of the elastic member 18, and the center moving block 130 slides to move the upper portion of the glass wafer 20.

In the fourth step, the lower heater block 12 and the upper heater block 14 are heated at different temperatures so that the volume change due to thermal expansion of the silicon wafer 24 and the volume change due to thermal expansion of the glass wafer 20 are the same. do. For example, the lower heater block 12 may be heated to 300 ° C., and the upper heater block 14 may be heated to 280 ° C. Of course, such a heating temperature can be appropriately adjusted according to the material of the wafer.

In a fifth step, the primary high voltage is applied to the point pushing electrode 16. As a result, the glass wafer 20 and the silicon wafer 24 are anodized from the center to the outer circumferential direction.

For better bonding, when the current applied to the two wafers is reduced to a predetermined value or less by the formation of the anodic bonding according to the application of the first high voltage, a second high voltage is additionally applied to the upper heater block 14 to provide a glass wafer. It is preferable to completely bond the outer peripheral portion of the 20 and the silicon wafer 24. In this case, the anode junction is formed by the primary high voltage from the center of the wafer to the predetermined region in the outer circumferential direction, and the remaining outer circumferential region is anode bonded by the secondary high voltage. Uniformity is improved.

When the anodic bonding is completed, sodium particles 30 are buried on the lower surface of the electrode intermediary module 100. The state at this time is shown in FIG. Here, since the electrode intermediary module 100 is not fixed to the anode bonding chamber, it can be easily taken out and washed.

Second Embodiment

Hereinafter, a second embodiment of the present invention will be described with reference to the accompanying drawings.

9 is a sectional view of principal parts of an anodic bonding chamber using an electrode intermediate module according to a second embodiment of the present invention.

As shown in FIG. 9, the electrode mediating module 200 according to the second embodiment has an annular moving block 235 and an annular mediating electrode 225 compared to the electrode mediating module 100 according to the first embodiment. It is substantially the same except that it is further coupled to the thermal medial block 110.

The electrode intermediary module 200 according to the second embodiment may correspond to a structure in which the anode bonding chamber uses at least one annular pushing electrode that forms concentric circles with the point pushing electrode in addition to the point pushing electrode.

On the other hand, with respect to the structure of the anode bonding chamber using the annular pushing electrode can be referred to Korean Patent No. 10-0446900 filed by the inventor of the present invention.

The anode bonding method when the annular intermediate electrode 225 is added is also similar to the above-described anode bonding method except that a voltage is applied to the annular intermediate electrode 225.

The embodiments of the present invention have been described above with reference to the accompanying drawings. However, it is to be noted that the present invention is not particularly limited only to the above-described embodiments, and that various modifications and changes can be made by those skilled in the art within the spirit and spirit of the appended claims as necessary.

As described above, according to the present invention, sodium particles are attached to an electrode intermediate module including an intermediate electrode formed of a material that is easily separated from the positive electrode bonding chamber, thereby allowing easy cleaning and continuous anode bonding.

In addition, according to the present invention, contamination of the interior of the chamber as a result of the anode bonding process is prevented, and only the electrode mediated module, which is a replaceable component, is contaminated and cleaned, thereby facilitating management of the process and equipment.

In addition, according to the present invention, an intermediate electrode formed of graphite as a material for applying voltage to the glass wafer is used, so that the point pushing electrode and the glass wafer do not directly contact each other, thereby preventing damage to the glass wafer or the point pushing electrode.

In addition, according to the present invention, since the intermediate electrode formed of graphite is used as the material to which the glass wafer applies voltage, the problem of current shortage and voltage failure when used in the stainless steel electrode is solved.

Claims (9)

An electrode-mediated module positioned between the upper heat block and the lower heat block of an anodic bonding chamber including a point heater electrode and an upper heater block and a lower heat block disposed at a center thereof, A thermal media block made of ceramic material formed in a disc shape having an empty center; A center moving block made of a ceramic material inserted into a space formed at the center of the thermal block to be slidably moved and formed in a disc shape having an empty center; And And an intermediate electrode slidably inserted into a space formed at the center of the center moving block and electrically connected to the point pushing electrode. According to claim 1, The thermal block, The lower end of the inner diameter is further formed with a protruding end protruding toward the inside, The central moving block is further formed with a protruding jaw protruding toward the outside of the outer diameter, The electrode intermediate module for the positive electrode junction chamber, characterized in that the movement distance of the central moving block is limited by the projecting end and the projection jaw. delete The method of claim 1, wherein the intermediate electrode, Electrode intermediate module for anodic bonding chamber, characterized in that formed of graphite material. The device of claim 1, further comprising: an annular mediated electrode; And And an annular moving block to which the annular intermediate electrode is slidably coupled. And the annular intermediate electrode and the annular moving block are concentrically coupled with the central moving block coupled to the thermal intermediate block. In the method of anodic bonding a silicon wafer and a glass wafer in an anodic bonding chamber, Stacking a silicon wafer and a glass wafer in order on the lower heater block; A heat moving block formed in a disc shape having an empty center in the upper portion of the glass wafer; Positioning an electrode media module including a media electrode coupled to be slidably movable in a space; A third step of contacting the electrode parameter module and the upper heater block; A fourth step of heating the lower heater block and the upper heater block at different temperatures such that the volume change due to thermal expansion of the silicon wafer and the volume change due to thermal expansion of the glass wafer are the same; And And a fifth step of applying a voltage to the point pushing electrode of the upper heater block to anodic-bond the silicon wafer and the glass wafer by an intermediate electrode electrically connected to the point pushing electrode. Anodic bonding method used. The method of claim 6, And a sixth step of applying a voltage to the upper heater block for better bonding of the glass wafer and the outer circumferential portion of the silicon wafer. The method of claim 6, wherein the fourth step, The heating method of the upper heater block and the lower heater block is a cathode bonding method using an electrode intermediate module, characterized in that 180 to 450 ℃. The method of claim 6, wherein the fifth step, The voltage applied to the point pushing electrode is a cathode bonding method using an electrode intermediate module, characterized in that 200 to 1000V.

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