JP2003282680A - Board lifer, clamp ring, and board processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a clamp ring and a board processing device using the same that can be used for a longer period of time. <P>SOLUTION: The clamp ring 10 is used to press down a wafer 8 and fix it onto a wafer holding body 1 in a sputtering film formation device, and it is provided with a first metal sheet 11 that is brought into contact with the wafer 8 when the wafer 8 is fixed, a second metal sheet 12 that is placed on the first metal sheet 11 and is smaller in width than the first metal sheet 11, and a sheet housing part 9a to house the first and the second metal sheets 11 and 12. The wafer is fixed on the wafer holding body while it is pressed down by means of the first metal sheet 11, and in this case, the first metal sheet 11 is bent in a dog leg shape at the end of the second metal sheet 12. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus such as a sputtering film forming apparatus, a clamp ring used for fixing a wafer in the substrate processing apparatus, and a substrate lifter.

[0002]

2. Description of the Related Art FIG. 5 is a sectional view showing a clamp ring used in a conventional sputtering film forming apparatus. The sputtering film forming apparatus includes a sputtering chamber (not shown). A wafer support 31 that supports a sputtering target (not shown) on the upper surface and a wafer 38 on the lower surface and serves as a substrate electrode is provided in the sputtering chamber.
Also, a clamp ring 30 for pressing the substrate is arranged.

The clamp ring 30 is for fixing the wafer 38 onto the wafer support 31 and has a contact portion 3.
2 and the step portion 34 are provided in the inner peripheral portion 36. The contact portions 32 are provided on the back side of the inner peripheral portion 36 of the clamp ring 30 at a plurality of positions at equal intervals in the circumferential direction, and press the wafer 38 against the heater in the sputtering apparatus, that is, the wafer support. The step portion 34 is provided inside the contact portion 32 over the entire circumference.

[0004]

In the conventional sputtering film forming apparatus described above, the sputtered particles have a step portion 34.
Between the wafer 38 and the wafer 38, and sputtered particles are deposited and embedded in that portion, so that the wafer 38
May stick to the step portion 34. If the wafer is stuck in this way, the wafer 38 cannot be removed from the clamp ring 30, and the wafer cannot be collected from the sputtering film forming apparatus. In this case, the sputter chamber is opened to the atmosphere and the operator takes out the wafer. At this time, a lot of time (about 6 to 10 hours) is spent to restart the sputtering film forming apparatus, which causes a decrease in the operation rate of the apparatus.

Further, a predetermined gap 37 (for example, 0..0) is formed between the wafer 38 and the step portion 34 of the clamp ring 30.
If it cannot be set to 2 mm), the sticking of the wafer to the clamp ring is particularly likely to occur. There are two possible reasons why such a predetermined gap cannot be established. One is due to the processing accuracy of the clamp ring when first processed (that is, the processing accuracy is low and a predetermined gap cannot be formed). The other is that the size of the clamp ring is changed by removing the wafer attached to the clamp ring and performing a regenerating process to remove the sputtered film from the clamp ring, and as a result, a predetermined gap can be taken. There are things you can't do.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a substrate lifter with improved substrate positioning accuracy and a substrate processing apparatus using the same. Another object of the present invention is to provide a clamp ring that can be used for a longer period and a substrate processing apparatus using the clamp ring.

[0007]

In order to solve the above-mentioned problems, a substrate lifter according to the present invention is a substrate lifter for positioning a substrate in a substrate processing apparatus, and a substrate mounting surface on which the substrate is mounted and the substrate mounting surface. A tapered surface connected to the mounting surface, wherein the tapered surface guides the substrate when the substrate is mounted on the substrate mounting surface.

Since the substrate lifter has a tapered surface, this tapered surface serves as a guide when the substrate is dropped onto the substrate mounting surface. The tapered surface causes the substrate to be dropped onto the substrate mounting surface, and at this time, the substrate can be accurately positioned and the substrate can be mounted on the substrate mounting surface.

Further, the substrate lifter according to the present invention further includes a fitting tapered surface arranged outside the tapered surface, and the fitting tapered surface receives the surface when positioning the substrate. It is preferable that the surface has the same inclination as the tapered surface formed on the member.

Further, in the substrate lifter according to the present invention, the substrate may be a semiconductor wafer and the substrate processing apparatus may be a sputtering film forming apparatus.

A clamp ring according to the present invention is a clamp ring for fixing a substrate by pressing it onto a substrate holder in a substrate processing apparatus, and a first sheet that comes into contact with the substrate when fixing the substrate, and a first sheet. A second sheet having a width narrower than that of the first sheet and a sheet accommodating portion for accommodating the first sheet and the second sheet, which is disposed on the upper surface of the first sheet. The first sheet is pressed and fixed, and at that time, the first sheet is fixed while being bent in a dogleg shape at the end portion of the second sheet.

According to the above clamp ring, the first sheet and the second sheet are accommodated in the sheet accommodating portion, and the substrates are pressed against the substrate holder via the first sheet. Sheets can be replaced after substrate processing. Therefore, the clamp ring can be used for a longer period of time.

Further, in the clamp ring according to the present invention, it is preferable that each of the first sheet and the second sheet is a metal sheet.

The clamp ring according to the present invention has a clamp surface for pressing the substrate in the clamp ring for fixing the substrate by pressing it on the substrate holder in the substrate processing apparatus, and the clamp surface is a curved surface. Is characterized by.

According to the above clamp ring, since the clamp surface is a curved surface, the particles for processing do not wrap around to the contact portion between the clamp surface and the substrate when processing the substrate.
As a result, the number of times the clamp ring is used can be dramatically increased.

In the clamp ring according to the present invention, it is preferable that the curved surface has a curvature different from that of the end surface of the substrate.

In the clamp ring according to the present invention, the substrate may be a semiconductor wafer and the substrate processing apparatus may be a sputtering film forming apparatus.

The substrate processing apparatus according to the present invention includes a chamber for processing a substrate, a substrate lifter arranged in the chamber for positioning the substrate, a substrate holder arranged in the chamber for holding the substrate, and And a clamp ring for pressing and fixing the substrate on the substrate holder, wherein the substrate lifter is the substrate lifter according to claim 1.

Further, in the substrate processing apparatus according to the present invention, the clamp ring may be the clamp ring according to claim 4 or 6.

A substrate processing apparatus according to the present invention includes a chamber for processing a substrate, a substrate lifter arranged in the chamber for positioning the substrate, a substrate holder arranged in the chamber for holding the substrate, and A clamp ring for pressing and fixing the substrate to the substrate holder, the clamp ring being the clamp ring according to claim 4 or 6.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are cross-sectional views illustrating a procedure of fixing a wafer in a sputtering chamber of a sputtering film forming apparatus according to the first embodiment of the present invention.

The sputtering film forming apparatus has a sputtering chamber (not shown). In this sputtering chamber, as shown in FIG. 1, a sputtering target (not shown) is arranged on the upper surface, a wafer support 1 that supports the wafer 8 and serves as a substrate electrode, and a clamp ring 10 that holds the substrate are arranged on the lower surface. ing. In addition, a substrate lifter 3 on which a wafer 8 transferred to a sputtering chamber by a wafer handler robot (not shown) is placed is disposed in the sputtering chamber. Each of the substrate lifter 3 and the wafer support 1 is configured to be vertically movable by a drive mechanism (not shown). Board lifter 3
Is for positioning the wafer.

When the wafer 8 is set in the sputtering chamber, first, the wafer 8 is transferred to the sputtering chamber by the wafer handler robot and placed on the substrate lifter 3. The substrate lifter 3 is mounted on the wafer mounting surface 3
a, and is configured to mount the wafer 8 on the wafer mounting surface 3a. Also, the board lifter 3
A tapered surface 3b connected to the wafer mounting surface 3a is formed on the. The tapered surface 3b serves as a guide when the wafer 8 is dropped onto the wafer mounting surface 3a. The wafer 8 is dropped onto the wafer mounting surface 3a by the tapered surface 3b, and at this time, the wafer 8 is mounted on the wafer mounting surface 3a with accurate positioning. Further, the substrate lifter 3 can adjust the diameter of the wafer mounting surface 3a according to the size of the wafer 8 to be mounted.

In the conventional substrate lifter, the wafer is dropped on the wafer mounting surface, but it does not have a taper surface and has a certain amount of looseness (backlash) so that the wafer can be moved back and forth on the wafer mounting surface. There is a margin to move about ± 1mm to the left and right, and it can rotate to some extent. Therefore, when the wafer is moved upward by the substrate lifter, the wafer moves because the wafer is on the metal. Therefore, when the wafer is pressed by the clamp ring, the wafer may be displaced. On the other hand, in the present embodiment, as described above, the wafer can be fixed at an accurate position on the wafer mounting surface, and the deviation of the film formation surface due to the positional deviation of the wafer can be prevented. Therefore, it is possible to reduce the occurrence of film formation defects and improve productivity.

Next, as shown in FIG. 2, the substrate lifter 3
Is moved upward by a drive mechanism to combine the substrate lifter 3 with the clamp ring 10. The clamp ring 10 is provided with a recess for receiving the substrate lifter 3 rising from below. This concave portion is formed by a horizontal surface 10a and a tapered surface 10b connected to it. The tapered surface 10 is arranged outside the substrate lifter 3. In addition, the clamp ring 1 is attached to the substrate lifter 3.
A convex portion that fits into the zero concave portion is provided. This convex portion has a horizontal surface 3c and a tapered surface 3 connected to it.
It is formed by d. Therefore, the substrate lifter 3
While the tapered surface 3d of the convex portion of is guided by the tapered taper 10b of the concave portion of the clamp ring 10, the horizontal surface 3c of the convex portion of the substrate lifter 3 and the horizontal surface 10a of the concave portion of the clamp ring 10 are brought into contact with each other, and the concave portion and the convex portion are Fit together.
In this manner, the clamp ring 1 is guided by the tapered surface 10b of the concave portion and the tapered surface 3d of the convex portion.
0 and the substrate lifter 3 can be accurately positioned relative to each other, and as a result, the wafer 8 mounted on the substrate lifter 3 and the clamp ring 10 can also be accurately positioned relative to each other.

As described above, when the concave portion of the clamp ring and the convex portion of the substrate lifter are fitted together, the tapered surface 10
Even if b and 3d rub against each other and dust is generated,
Since the tapered surface 3d is arranged on the outer side of the wafer mounting surface 3a of the substrate lifter 3, dust is not deposited on the wafer 8. That is, the structure is such that particles are less likely to be generated on the wafer when the clamp ring is positioned.

Next, as shown in FIG. 3, the wafer support 1
Is moved upward by the drive mechanism. As a result, the wafer 8 is moved upward while the wafer 8 is placed on the wafer support 1. Then, the edge (outer periphery) of the wafer 8 comes into contact with the first metal sheet 11 attached to the clamp ring 10. The clamp ring 10 fixes the wafer 8 on the wafer support 1. The clamp ring 10 is provided with a pressing portion 9 that presses when fixing the wafer, and the pressing portion 9 is provided over the entire circumference of the wafer. A sheet storage portion 9a is provided below the pressing portion 9, and the sheets and the storage portions 9a are provided at a plurality of positions at equal intervals in the circumferential direction of the wafer. A first metal sheet 11 and a second metal sheet 12 are inserted in the sheet storage portion 9a. In the sheet storage portion 9a, the second metal sheet 12 is arranged so as to overlap the first metal sheet 11. The width of the first metal sheet 11 is formed narrower than the width of the second metal sheet 12. Therefore, the wafer support 1 is moved upward and
By pushing the metal sheet 11 upward with the edge of the wafer 8, the first metal sheet 11 is bent in a dogleg shape with the inner side of the second metal sheet 12 as a fulcrum, as shown in FIG. The wafer 8 is pressed against the wafer support 1 by the portion 9.

Since the first metal sheet 11 and the second metal sheet 12 are inserted into the sheet accommodating portion 9a of the clamp ring 10 for fixing the wafer 8 on the upper surface of the wafer support 1, the wafer 8 as shown in FIG. When is fixed to the wafer support 1, a predetermined gap between the wafer 8 and the holding portion 9 of the clamp ring can be accurately ensured. Further, the first metal sheet 11 which is initially flat is deformed into a dogleg shape due to the weight of the clamp ring 10, and the first metal sheet 11 contacts only on the circumferential line of the side edge of the wafer 8. This makes it possible to minimize the contact area with the wafer 8. Also, by changing the size (ie, width) of the inner and outer peripheries of the second metal sheet 12, the fulcrum of the first metal sheet 11 that is deformed into a dogleg shape can be changed. It is possible to adjust the appropriate deformation amount to an appropriate value.

Next, after forming a sputtered film on the wafer 8, the clamp ring 10 is separated from the wafer 8 by moving the wafer support 1 downward by a driving mechanism. At this time, the first metal sheet 11 exerts a spring force to return to the initial flat shape. As a result, the wafer 8 can be reliably separated from the clamp ring pressing portion 9. Since the spring force of the first metal sheet 11 is used in this way, it is possible to prevent the wafer from sticking to the clamp ring as in the conventional sputtering film forming apparatus. Therefore, since the wafer can be easily recovered from the sputtering film forming apparatus, it is not necessary to spend a lot of time to restart the sputtering film forming apparatus as in the conventional case, and it is possible to suppress a decrease in the operation rate of the apparatus.
Moreover, since the first metal sheet 11 is initially flat,
When the wafer separates from the first metal sheet 11, the film forming surface of the wafer is not rubbed.

Further, in the conventional sputtering film forming apparatus, the gap between the clamp ring and the wafer could not be stabilized due to the processing accuracy and maintenance frequency of the clamp ring. On the other hand, in the present embodiment, since the first metal sheet 11 and the second metal sheet 12 are inserted in the sheet storage portion 9a of the clamp ring, the sputtered film is formed on a predetermined number of wafers. The metal sheets 11, 12 can later be replaced, which makes it possible to stabilize the gap between the clamp ring and the wafer. This can prevent the wafer from sticking to the clamp ring.

In the conventional sputtering film forming apparatus, when the clamp ring is regenerated, the gap forming portion of the clamp ring is deformed by etching, and when the regeneration process is performed about 20 times, the clamp ring is used. I couldn't do it. On the other hand, in the present embodiment, since the metal sheets 11 and 12 are used, the number of times the clamp ring is used can be dramatically increased, which can be expected to contribute to cost reduction. The price of the metal sheet is around 1,000 yen per sheet, and the price of the clamp ring is about several hundred thousand yen. Therefore, it is considered that the cost reduction effect is great by prolonging the usage period of the clamp ring.

FIG. 4 is a sectional view showing the construction of a clamp ring according to a second embodiment of the present invention.
The same parts as those in FIG. 3 are designated by the same reference numerals, and only different parts will be described.

In order to avoid the sticking of the wafer to the clamp ring, which is a problem of the conventional clamp ring, paying attention to the fact that the end surface (side surface) of the wafer 8 is a curved surface, the clamp surface 21 of the clamp ring 10 is The curved surface has a different curvature from the end surface of the wafer 8. Therefore, since the clamp surface 21 and the end surface of the wafer 8 have different curvatures,
When the wafer 8 is pressed by the clamp ring, the two come into contact with each other with a line. That is, curved surfaces having different curvatures R are in contact with each other at points, and when the cross section is R, both are in contact with each other at a line.

Further, the contact portion 22 between the clamp surface 21 and the wafer 8 is located above the side surface of the wafer as shown in FIG. 4, and since the clamp surface 21 is a curved surface, a film is formed on the wafer 8 by sputtering. At this time, the sputtered particles 23 do not go around to the contact portion 22. Therefore, it is possible to prevent the wafer from sticking to the clamp ring.

Further, even if the clamp ring 10 is subjected to a regenerating treatment such as washing, since it has a structure in which the clamp surface does not have an edge unlike the conventional clamp ring, much more regenerating treatment than the conventional clamp ring is performed. However, it is expected that the clamp ring 10 can be used.

Also in the second embodiment, the same effect as in the first embodiment can be obtained.

That is, it is possible to prevent the wafer from sticking to the clamp ring as in the conventional sputtering film forming apparatus. Therefore, since the wafer can be easily recovered from the sputtering film forming apparatus, it is not necessary to spend a lot of time to restart the sputtering film forming apparatus as in the conventional case, and it is possible to suppress a decrease in the operation rate of the apparatus. In addition, the number of times the clamp ring 10 is used can be dramatically increased, which can be expected to contribute to cost reduction.

The present invention is not limited to the above-described embodiment, but can be implemented with various modifications. For example,
Tapered surface 3 of substrate lifter in the first embodiment
Taper angle of d, taper surface 10b of clamp ring
The taper angle, the number of the holding portions 9 of the clamp ring, etc. can be changed to various appropriate angles. Further, the metal sheets 11 and 12 are not limited to metal as long as they have a spring force, and other sheets can be used. Further, the curvature of the clamp surface in the second embodiment can be changed to various appropriate curvatures.

[0039]

As described above, according to the present invention, it is possible to provide a substrate lifter with improved substrate positioning accuracy and a substrate processing apparatus using the same. Further, according to another aspect of the present invention, it is possible to provide a clamp ring that can be used for a longer period and a substrate processing apparatus using the clamp ring.

[Brief description of drawings]

FIG. 1 is a sectional view illustrating a procedure for fixing a wafer in a sputtering chamber of a sputtering film forming apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating a procedure of fixing a wafer in a sputtering chamber of a sputtering film forming apparatus according to the first embodiment of the present invention, and showing the next procedure of FIG.

FIG. 3 is a cross-sectional view illustrating a procedure of fixing a wafer in a sputtering chamber of a sputtering film forming apparatus according to the first embodiment of the present invention, and showing the next procedure of FIG. 2.

FIG. 4 is a cross-sectional view of a structure for explaining a clamp ring according to a second embodiment of the present invention.

FIG. 5 is a sectional view showing a clamp ring used in a conventional sputtering film forming apparatus.

[Explanation of symbols]

1, 31 ... Wafer support 3 ... Substrate lifter 3a ... Wafer mounting surface 3b ... Tapered surface 3c ... Horizontal surface of convex portion 3d ... Tapered surface of convex portion 8 ... Wafer 9 ... Holding portion 10 ... Clamp ring 10a ... Horizontal surface of concave portion Reference numeral 10b ... Tapered surface of concave portion 21 ... Clamping surface 22 ... Contact portion 23 ... Sputtered particle 30 ... Clamp ring 31 ... Wafer support 32 ... Contact portion 34 ... Step portion 36 ... Inner peripheral portion 37 ... Gap 38 ... Wafer

Claims (11)

[Claims] 1. A substrate lifter for positioning a substrate in a substrate processing apparatus, comprising: a substrate mounting surface on which a substrate is mounted; and a tapered surface connected to the substrate mounting surface, wherein the tapered surface is the substrate. A substrate lifter for guiding a substrate when the substrate is mounted on the substrate mounting surface. 2. A tapered surface for fitting disposed outside the tapered surface, wherein the tapered surface for fitting is substantially the same as the tapered surface formed on a member for receiving the surface when positioning the substrate. The substrate lifter according to claim 1, wherein the substrates are surfaces having the same inclination. 3. The substrate lifter according to claim 1, wherein the substrate is a semiconductor wafer, and the substrate processing apparatus is a sputtering film forming apparatus. 4. A clamp ring for fixing a substrate by pressing it onto a substrate holder in a substrate processing apparatus, the first sheet being in contact with the substrate when the substrate is fixed, and the first sheet arranged on the first sheet. A second sheet having a width narrower than that of the first sheet, and a sheet accommodating portion for accommodating the first sheet and the second sheet, wherein the substrate is pressed and fixed to the substrate holder via the first sheet. In that case, the clamp ring is characterized in that the first sheet is fixed while being bent in a dogleg shape at the end portion of the second sheet. 5. The clamp ring according to claim 4, wherein each of the first sheet and the second sheet is a metal sheet. 6. A clamp ring for fixing a substrate by pressing it onto a substrate holder in a substrate processing apparatus, wherein the clamp ring has a clamp surface for pressing the substrate, and the clamp surface is a curved surface. . 7. The clamp ring according to claim 6, wherein the curved surface has a curvature different from that of the end surface of the substrate. 8. The clamp ring according to claim 4, wherein the substrate is a semiconductor wafer, and the substrate processing apparatus is a sputtering film forming apparatus. 9. A chamber for processing a substrate, a substrate lifter arranged in the chamber for positioning the substrate, a substrate holder for holding the substrate in the chamber, and a substrate held by the substrate holder. A substrate processing apparatus, comprising: a clamp ring that is attached and fixed; and the substrate lifter is the substrate lifter according to claim 1. 10. The clamp ring according to claim 4 or 6.
The substrate processing apparatus according to claim 9, which is the clamp ring according to claim 9. 11. A chamber for processing a substrate, a substrate lifter arranged in the chamber for positioning the substrate, a substrate holder for holding the substrate in the chamber, and a substrate held by the substrate holder. A substrate processing apparatus, comprising: a clamp ring that is attached and fixed; and the clamp ring is the clamp ring according to claim 4 or 6.