JP2001323371A - Sputtering system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an extremely uniform film thickness distribution of ±0.5% or below without enlarging the size of a target and also lengthing the distance between the target and a substrate by fixing the relation between the diameter D of a revolving orbit and the distance H between the target and the substrate to the prescribed one, in a revolving/rotating substrate holder system. SOLUTION: When the effective diameter L of a circular target 10 is 160 mm, and the diameter (d) of a substrate 12 is 100 mm, in the case the diameter D of a revolving orbit is set to 210 mm, and the distance H between the target and the substrate to 107 mm, the intrasurface film thickness distribution in the substrate can be controlled to ±0.5% or below. At this time, 5 pieces of substrates can be arranged on the revolving orbit. When the diameter (d) of the substrate is 125 mm, D is set to 250 mm, and H to 137 mm. When the diameter (d) of the substrate is 150 mm, D is set to 280 mm, and H to 160 mm. In any case, 5 pieces of substrates can be arranged on the revolving orbit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a sputtering apparatus having a revolving substrate holder device.

[0002]

2. Description of the Related Art In a sputtering apparatus, it is known to use a self-revolving substrate holder apparatus in order to improve a film thickness distribution on a substrate. The self-revolution type substrate holder device is roughly classified into a type in which the center of the orbit is eccentric with respect to the center of the target, and a type in which the center of the orbit coincides with the center of the target. As the former known examples, JP-A-8-239760 (the number of substrate holders is eight) and JP-A-7-292471.
No. (the number of substrate holders is six), JP-A-10-1803
No. 1 (the number of substrate holders is six), JP-A-11-335
No. 835 (four substrate holders), JP-A-6-25
No. 6940. Of these, Japanese Patent Application Laid-Open No. 6-256940
In No. 2, ± 2% was obtained as the film thickness distribution on the substrate.

A known example of the latter type in which the center of the orbit coincides with the center of the target is disclosed in JP-A-7-26.
378 and JP-A-10-2988752. Japanese Unexamined Patent Application Publication No. 7-26378 discloses that the number of substrate holders is four, and that a film thickness distribution on a substrate of ± 5% is obtained when an electron beam evaporation source is used as a film formation source. JP 1
No. 0-2988752 discloses that each substrate revolves around itself in a state inclined with respect to the target surface.
There are four revolving substrate holder units. Four substrate holders are fixed to each of the substrate holder units. As a distribution of the sheet resistance value of the thin film on the substrate, ± 2% is obtained.

[0004]

Among the thin films formed by the sputtering apparatus, there are some thin films having particularly severe specifications of the in-plane film thickness distribution on the substrate. For example, a surface acoustic wave (S
In the manufacture of AW) filters, a film thickness distribution of a thin film formed on a substrate is required to be about ± 0.5%, and it has been difficult to meet such specifications. The film thickness distribution can be improved by using the above-described known revolving substrate holder device, but it is still up to about ± 2%, and it is difficult to obtain a better film thickness distribution. of course,
If the distance from the target to the substrate is very large,
Although the film thickness distribution itself may be improved, the film deposition rate and the deposition efficiency are remarkably reduced, making it unusable as an actual production apparatus. Alternatively, using a very large target compared to the substrate improves the film thickness distribution,
Also in this case, the deposition efficiency is significantly reduced, and the target becomes very expensive.

[0005] The present invention has been made to solve such a problem, and its object is to provide a
An object of the present invention is to provide a sputtering apparatus capable of obtaining a film thickness distribution of ± 0.5% or less without increasing the size and without increasing the distance between the target and the substrate.

[0006]

Means for Solving the Problems The present inventor has proposed a sputtering apparatus having a revolving type substrate holder apparatus without increasing the target size so much.
Further, the present inventors have found an optimum geometrical condition such that the in-plane film thickness distribution on the substrate becomes ± 0.5% or less without increasing the distance between the target and the substrate. According to the present invention, the effective diameter L of the target is 100 to 220 m.
It provides optimal geometric conditions for those within the range of m. Here, the effective diameter of the target means the diameter of a region (that is, an erosion region) where sputtering is actually performed on the surface of the target. The self-revolving substrate holder device has five or six circular substrate holders. Substrate diameter 100mm, 1
In the case of 25 mm and 150 mm (corresponding to nominally 4 inch, 5 inch and 6 inch substrates, respectively), five substrate holders are provided, and the diameter of the substrate is 75 mm.
In the case of (corresponding to a nominally 3-inch substrate), six substrate holders are provided. Each substrate holder can hold one substrate. Each substrate holder revolves such that its center passes through a circular orbit, and each substrate holder rotates around its own center. The substrate holding surface of each substrate holder is parallel to the surface of the target. When viewed from a direction perpendicular to the target, the center position of the orbit coincides with the center position of the target.

The size of the substrate to be used is 75 mm, 100 m
The reason why the diameters are set to m, 125 mm, and 150 mm is in consideration of the size of a commercially available wafer. These substrate sizes correspond to nominally 3 inch, 4 inch, 5 inch and 6 inch wafers, respectively. By the way, for example, a nominal 4 inch wafer has a diameter of 101.6 mm, but the effective range for fabricating devices and the like is substantially 1 mm.
The range is within 00 mm. Therefore, considering the in-plane film thickness distribution on the substrate, a 4-inch wafer has a diameter of 1
It is enough to consider the case of 00 mm. Therefore, in the present invention, for example, a substrate having a diameter of 100 mm
It encompasses commercially available nominal 4 inch wafers.
In addition, the substrate used in the present invention only needs to be roughly circular,
Circular wafers with an orientation flat formed are naturally included.

In the present invention, in order to reduce the in-plane film thickness distribution on the substrate to ± 0.5% or less, the distance H between the target and the substrate (unit: mm) and the diameter D of the orbit of revolution (unit: mm) are required. To the following relationship: Considering a coordinate space in which H and D are taken on two orthogonal coordinate axes, when the coordinate point composed of D and H is 100 mm in diameter of the substrate, the following (A)
(C) in the area surrounded by the three straight lines. (B) D = Aa × H + Ab (b) D = Ba × H + Bb (c) H = 160

In this case, the gradient Aa in the straight line (a)
And the intercept Ab and the slope Ba in the straight line (b).
And the intercept Bb depends on the diameter d of the substrate and the effective diameter L of the target. When the diameter d of the substrate is 100 mm,
Using the effective diameter L of the target (the unit is mm), it is calculated by the following (d) to (g). (D) Aa = −3.340E-5L ² + 7.022E-3L + 6.315E-1 (e) Ab = 7.885E-3L ² −1.465L + 1.475E + 2 (f) Ba = −2.913E-5L ² +5. 062E-3L + 1.236 ^{(door) Bb = 8.886E-3L 2 -1.645L} + 1.137E + 2

That is, Aa, Ab, Ba, and Bb are each a quadratic expression of L. Note that, in the above-described quadratic expression, the symbol E means a power of 10. For example,
"E-5" means "10 to the fifth power of 5".
Therefore, "-3.340E-5" becomes "-0.000".
03340 ”. In the above quadratic equation,
Let the coefficient of the square of L be U, let the coefficient of the first power of L be V,
Let W be a constant part that does not depend on
V and W are as shown in the table of FIG. In FIG. 18, when looking at the row where the substrate diameter d = 100 mm,
The values of the coefficients U, V, W in the quadratic expressions of Aa, Ab, Ba, Bb are shown.

Similarly, the table of FIG. 18 shows that the coefficients U, A of each quadratic expression for obtaining Aa, Ab, Ba, and Bb from L also for the case where the substrate diameter d is 75 mm, 125 mm, and 150 mm. The values of V and W are shown.

Summarizing the above points, when the substrate diameter d and the effective diameter L of the target are determined, A is obtained from the table shown in FIG.
a, Ab, Ba, Bb are determined, and these Aa, Ab,
When Ba and Bb are determined, the two straight lines (the diameter D of the orbit of revolution and the distance H between the target and the substrate) of the above-mentioned (a) and (b) are obtained.
Is defined as a straight line in a coordinate space in which the coordinate system is defined as a rectangular coordinate axis. Thus, an area surrounded by these two straight lines and the straight line of H = 160 mm is determined. The coordinates consisting of D and H in this region are the optimal combination of D and H. When a target is sputtered using this combination to form a film on a substrate, each substrate has a good ± 0.5% or less. A good film thickness distribution can be obtained.

[0013]

FIG. 1 is a perspective view showing a positional relationship between a target and a substrate in one embodiment of the sputtering apparatus of the present invention. Above there is a circular target 10 and below there are five generally circular substrates 12. These substrates 12 revolve by the action of a self-revolving substrate holder device 14. A thin film is formed on these substrates 12 by sputtering. This arrangement has the advantage that the substrate is not directly exposed to the plasma, since the substrate does not directly face the target.

First, the overall configuration of the sputtering apparatus of this embodiment will be described. FIG. 2 is a front sectional view of the sputtering apparatus. A cathode 18 is attached to the vacuum vessel 16, and the target 10 is fixed to the cathode 18. The cathode 18 is a magnetron cathode and houses a magnet unit 20 inside. The magnet unit 20 can rotate inside the cathode 10, and the center of the magnet unit 20 is eccentric with respect to the center of rotation.

A film is formed on the substrate 12 using the cathode 18 as follows. Exhaust port 30 of vacuum vessel 16
A sputtering gas (for example, argon gas) is introduced from the gas introduction system 32 while maintaining the vacuum at a predetermined pressure while the inside of the vacuum vessel 16 is evacuated by the exhaust pump connected to the vacuum pump.
Cooling water 34 is allowed to flow inside the cathode 18 and the cathode 1
DC power (or high-frequency power) is supplied to the power supply 8 from the power supply 36. As a result, plasma is generated in the vacuum chamber 16 and the target 10 is sputtered with argon ions in the plasma to form a film on the substrate 12.

Next, the substrate holder device 14 will be described.
Below the target 10 is a revolving substrate holder device 14. The substrate holder device 14 has one pallet 22 and five substrate holders 24. Each substrate holder 24 holds one substantially circular substrate 12.
Only one can be attached. The “substantially” circular substrate is, for example, a wafer on which an orientation flat is formed. Of course, a completely circular substrate may be used. The pallet 22 can rotate with respect to the vacuum vessel 16, and further, each substrate holder 24 can rotate with respect to the pallet 22.
The respective substrate holders 24 are attached so as to be spaced apart from the center of rotation of the pallet 22 so as to be at equal intervals. A large gear 26 is fixed to a rotating shaft of the pallet 22, while a small gear 28 is fixed to a rotating shaft of the substrate holder 24. Since each small gear 28 meshes with the large gear 26, when the pallet 22 rotates, the five substrate holders 24 also rotate in conjunction with the rotation. Thus, the substrate holder 24 rotates (revolves) around the rotation center of the pallet 22 and rotates (rotates) around its own center.

The gear ratio between the large gear 26 and the small gear 28 is 5 to 1.
It is. Therefore, when viewed from above, when the large gear 26 makes one rotation in the counterclockwise direction, the small gear 28 makes five rotations in the clockwise direction. However, in the meantime, since the substrate holder 24 attached to the small gear 28 revolves one turn in the counterclockwise direction,
As a whole, while the large gear 26 makes one rotation in the counterclockwise direction, the small gear 28
That is, four rotations in the clockwise direction. The drive mechanism for revolving the substrate holder on its own axis is not limited to such a gear mechanism, but may employ another drive mechanism such as a belt type or a magnet type. Further, even when the gear mechanism is employed, an arbitrary gear ratio can be employed without being limited to the gear ratio described above.

FIG. 3 is a plan view of the substrate holder device.
Rotation center Os of each substrate holder 24 (substrate holder 24
Is rotated around the rotation center Op of the pallet 22, and its trajectory becomes a circular orbit 38. The five substrate holders 24 are arranged on the same revolution orbit 38 at equal intervals. The diameter D of the orbit 38 has a great influence on the film thickness distribution on the substrate 12 as described later.

Next, returning to FIG. 1, the relative positional relationship between the target and the substrate, which is important for the present invention, will be described.
The effective diameter of the circular target 10 is L. The actual outer shape of the target is slightly larger than L. The diameter of the substantially circular substrate 12 is d. The diameter of the orbit 38 of the substrate 12 is D. The vertical distance between the surface of the target 10 and the surface of the substrate 12 (that is, the target 10
Is the distance measured in the direction of the normal to the surface of the target), which is called the target-substrate distance. Circular target 10
When a substrate having a substantially circular shape 12 is used, if the above four dimensions are determined, the positional relationship between the target 10 and the substrate 12 will be determined.

FIG. 15 shows the cross-sectional shape of the erosion region of the target used in the sputtering apparatus shown in FIG. The horizontal axis is the distance from the target center, and the vertical axis is the erosion depth measured from the target surface before use. Since the sputtering apparatus of FIG. 2 uses the magnetron cathode provided with the eccentric rotary magnet, the erosion area of the target is made uniform as compared with the magnetron cathode provided with the non-rotating magnet. The actual outer diameter of this target is 1
64 mm, but the erosion zone diameter is about 160
mm. This 160 mm is the effective diameter of the target. In order to study the film thickness distribution on the substrate, it is necessary to consider not the external dimensions of the target but the region where sputter particles are actually emitted. Thus, in this specification, the effective diameter of the target is significant.

Next, the effective diameter L of the target is set to 160 m.
m (the actual outer diameter of the target is 164 mm) and the diameter d of the substrate is 100 mm (approximately equal to the effective area of the nominal 4 inch substrate). Explanation will be given on how the distance H between the substrates affects the numerical value of the film thickness distribution. FIG.
Is a graph of a simulation result of a numerical value of a film thickness distribution under such conditions. The horizontal axis is the diameter D of the orbit.
(Mm), and the vertical axis indicates the distance H (mm) between the target and the substrate. This graph shows the numerical value of the in-plane film thickness distribution of one substrate, and is made as follows. A large number of combinations of D and H when the numerical value of the film thickness distribution is ± 1% are obtained, plotted on a graph, and the points are connected to obtain a contour line of ± 1%. Similarly, by obtaining a large number of combinations of D and H when the numerical value of the film thickness distribution becomes ± 0.5%, a contour line of ± 0.5% can be obtained. A hatched area surrounded by contour lines of ± 0.5% is a region where a good film thickness distribution within ± 0.5% is obtained.

An object of the present invention is to find a geometrical condition such that the in-plane film thickness distribution of a thin film deposited on a substrate becomes ± 0.5% or less. FIG. 10 is a diagram in which two straight lines A and B are drawn so as to surround the hatched region in FIG. 4 from both sides. As described above, the above-mentioned hatched area can be approximately approximated by an area sandwiched between two straight lines. Generally, any straight line in the graph of FIG.
= AH + b. Where a and b
Is a constant. a is equal to the slope of the line, and b is equal to the intercept of the line. When the value of this constant is obtained, the straight line A is a = 0.
9, b = 115. The straight line B has a = 1.3 and b = 78.
It is. In the following description, the slope of the straight line A is represented by Aa, the intercept is represented by Ab, the slope of the straight line B is represented by Ba, and the intercept is represented by Bb. The coordinates of the intersection C of the straight lines A and B are D = 199 mm, H
= 93 mm. Therefore, the in-plane film thickness distribution is set to ± 0.1.
In order to make it 5% or less, the distance H between the target and the substrate is set to 93.
mm, the diameter D of the orbit of revolution should be larger than 199 mm, and the combination of D and H should be in the shaded area between the straight lines A and B.
When the distance H between the target and the substrate is increased, the film deposition rate and the deposition efficiency are reduced.
Should be as small as possible. Therefore, in the graph of FIG. 10, the condition at the point C is the optimum condition in which the film thickness distribution is good and the film deposition rate is high. Then, even when H is set to be larger than the point C, H should be set to 160 mm or less. If H is made larger than this, the film deposition speed and deposition efficiency will be greatly reduced, making it unsuitable for an actual production device. Therefore, a preferred combination of D and H is
This is within an area surrounded by three straight lines A and B and a straight line of H = 160 mm.

In FIG. 1, when a circular substrate having a diameter d is arranged on the orbit 38, how many substrates can be arranged at the maximum depends on the diameter d of the substrate and the diameter D of the orbit.
And it depends on the ratio. This will be described below. D = k
When d is set (where k is a proportional coefficient), n substrates having a diameter d are closely arranged in a circular shape, and the diameter of a circle passing through the center of each substrate is determined (corresponding to a revolution orbit). Assuming that D, the relation between the number n and the proportional coefficient k (= D / d) can be obtained from the geometric relation, and is as follows. n = 2 pieces k = 1.000 n = 3 pieces k = 1.155 n = 4 pieces k = 1.414 n = 5 pieces k = 1.701 n = 6 pieces k = 2.000 n = 7 pieces k = 2.305 n = 8 k = 2.613

Accordingly, for an arbitrary k, the maximum number of substrates to be arranged at that time is as follows. k = 1.000-1.155 2 sheets at maximum k = 1.155-1.414 3 sheets at maximum k = 1.414-1.701 4 sheets at maximum k = 1.701-2.000 at maximum 5 sheets k = 2. 000 to 2.305 6 sheets at the maximum k = 2.305 to 2.613 7 sheets at the maximum

When an actual revolving board holder is designed, it is necessary to keep a certain distance between the boards, so that the value of k is a little larger than this.

Taking into account the maximum number of substrates arranged as described above, the following can be said. In the graph of FIG.
Considering the ratio of the above-mentioned optimal D = 199 mm (that is, the minimum value of the preferable value of D) to 100 mm, k = 1.96. At this time, from the relationship between k and the maximum number of arrangements, it can be seen that up to five substrates can be arranged. Therefore, under the conditions of FIG. 10, it is optimal that the number of substrate holders of the revolving substrate holder device is five.

Next, a case where a substrate having another diameter is used will be described. FIG. 8 is a graph similar to FIG. 4 when the diameter d of the substrate is 125 mm (approximately equal to the effective area of the nominal 5 inch substrate). The effective diameter L of the target is 160 mm, which is the same as in FIG. FIG. 11 is a graph obtained by approximating a hatched region in which the in-plane film thickness distribution becomes ± 0.5% or less in the graph of FIG. 8 with two straight lines as in FIG. In this graph, Aa = 0.95, Ab = 1
14, Ba = 1.29 and Bb = 77. The coordinates of the intersection C are H = 109 mm and D = 217 mm. Then, D = 217 mm for d = 125 mm is k =
1.709, and from the relationship between k and the maximum number of substrates, five substrates can be disposed at the maximum.

FIG. 9 shows that the diameter d of the substrate is 150 mm (nominal 6).
5 is a graph similar to FIG. 4 in the case where the effective area is substantially equal to the effective area of the inch substrate. The effective diameter L of the target is 160 mm, which is the same as in FIG. And FIG.
In the graph of FIG. 9, a shaded region where the in-plane film thickness distribution is ± 0.5% or less is approximated by two straight lines as in FIG. In this graph, Aa = 1.09,
Ab = 98, Ba = 1.31, and Bb = 74. The coordinates of the intersection C are H = 142 mm, D = 260 mm
It is. And D = 260m for d = 150mm
m becomes k = 1.706, and from the relationship between k and the maximum number of arrangements, five substrates can be arranged at the maximum.

FIG. 13 shows that the diameter d of the substrate is 75 mm (nominal 3).
5 is a graph similar to FIG. 4 in the case where the effective area is substantially equal to the effective area of the inch substrate. The effective diameter L of the target is 160 mm, which is the same as in FIG. And FIG.
In the graph of FIG. 13, a hatched area where the in-plane film thickness distribution is ± 0.5% or less is approximated by two straight lines as in FIG. In the graph for d = 75 mm, the boundary of the hatched area is curved, and the two boundary lines sandwiching the hatched area must strictly represent D by the cubic expression of H. However, in this case, the two straight lines A and B represent an oblique line region so that the target-substrate distance H can be appropriately fitted to a relatively small region. Then, Aa = 0.74, Ab = 119, Ba = 1.1.
6, Bb = 95. The coordinates of the intersection C are H = 57m
m, D = 161 mm. Then, D = 161 mm for d = 75 mm is k = 2.147, and in this case, up to six substrates can be arranged in this case from the relationship between k and the maximum number of arrangements.

FIG. 17 is a table summarizing the above points for four types of substrates when the effective diameter L of the target is 160 mm. This FIG.
Shows the coordinates (D, H) of Aa, Ab, Ba, Bb and intersection C for three target sizes with respect to four types of substrate sizes. The numerical values that have been described are described.

By the way, when the diameter d of the substrate is increased to 200 mm (substantially equal to the effective area of the nominal 8 inch substrate), as can be inferred from FIGS. 10 to 12, the film thickness distribution is reduced to ± 0.5% or less. Such a combination of D and H no longer exists in the range of H = 160 mm or less, and is unsatisfactory in terms of film deposition speed and deposition efficiency. Therefore, the present invention takes into account both the film thickness distribution and the film deposition rate, and the effective diameter L of the target is 160 mm.
For the wafer size available on the market,
A substrate having a diameter d of up to 150 mm (corresponding to a nominally 6-inch substrate) will be used.

Next, the results of actual film forming experiments will be described. FIG. 5 shows L = 160 mm, d = 100 mm, H = 107 m
The in-plane film thickness distribution on the substrate 12 when the film is actually formed under the geometric conditions of m and D = 210 mm is shown by contour lines. The geometric condition at this time corresponds to point E on the graph of FIG. Other film forming conditions when the graph of FIG. 5 was obtained were as follows: a film forming pressure of 0.15 Pa, a target input power of 2 kW DC, a film thickness of 400 nm, and a target thickness of 5 m.
The revolution speed of the pallet of the aluminum / titanium alloy and the self-revolving substrate holder device is 68 rpm. In the graph of FIG. 5, the maximum film thickness is within 99.5% or more of the maximum film thickness in almost the entire surface of the substrate, and the in-plane film thickness distribution is ± 0.25%. Therefore, the actual film thickness distribution at point E in the shaded region of the simulation graph of FIG. 4 is sufficiently within ± 0.5%, and the simulation result and the experiment result are in good agreement. The adhesion efficiency at this time is calculated to be 36%.
The substrate temperature when forming a 400 nm film was 80 ° C.

Next, examples of the arrangement of substrates for each substrate size will be described. FIG. 7A is an example of a substrate arrangement when d = 100 mm. L = 160 mm, H = 107 mm, D = 210
mm. This corresponds to point E in the graph of FIG. Substrate 12
Are placed on the substrate holder 24 and the substrate holder 24 is mounted on the pallet 22. FIG. 7 (b)
Is an example of substrate arrangement when d = 125 mm. L = 16
0 mm, H = 135 mm, D = 250 mm. FIG.
Corresponds to the point F in the graph. FIG. 7C shows d = 150 m.
It is an example of board arrangement at the time of m. L = 160 mm, H = 1
60 mm, D = 280 mm. This corresponds to point G in the graph of FIG.

In each of these three types of substrate sizes, five substrates are arranged without much space.
Not only the film thickness distribution is very good, but also the adhesion efficiency is good. Further, since film formation can be simultaneously performed on five substrates with an extremely good film thickness distribution, productivity is excellent. In addition, when the sputtering apparatus is continuously operated using a commonly-used 25 wafer cassette, there is an advantage that there is no waste in the production process by forming a film every five wafers.

FIG. 16 shows an example of the substrate arrangement when d = 75 mm. L = 160 mm, H = 70 mm, D =
172 mm. This corresponds to point J in the graph of FIG.
In this case, six substrates can be arranged. Therefore, when the effective diameter L of the target is 160 mm, d = 75 m
When using the substrate of FIG.
To six.

In the above embodiment, the effective diameter L of the target
Is set to 160 mm, and L =
Simulations were performed for 101 mm and 216 mm in the same manner as for L = 160 mm. That is,
10 and 1 for L = 101 mm and 216 mm.
Graphs similar to 1, 12, and 14 were made, and the slopes and intercepts of the straight lines A and B were determined. The result is shown in FIG. In the list of FIG. 17, L = 101 mm and 216 mm
Also, Aa, Ab, Ba, at each substrate size.
Bb is shown.

FIGS. 19 to 22 show how the numerical values of Aa, Ab, Ba, and Bb change with the effective diameter L of the target in each substrate size.
FIG. 19 is a graph in which the numerical values of Aa, Ab, Ba, and Bb in the list of FIG. 17 are plotted on the vertical axis and the effective diameter L of the target is plotted on the horizontal axis for the substrate diameter d = 75 mm. The actual simulation is L = 101m
There are three points of m, 160 mm and 216 mm, and for L between them, these three points are interpolated by connecting them with a quadratic curve of L. The equation of the quadratic curve is as follows. Aa = −2.440E-5L ² + 3.995E-3L + 7.254E-1 Ab = 7.915E-3L ² −1.476L + 1.525E + 2 Ba = 3.116E-5L ² −1.457E-2L + 2.694 Bb = 3.172E− 3L ² + 1.822E-1L-1.536E + 1

When the effective diameter L of the target is determined, Aa, Ab, Ba, and Bb are obtained from these quadratic expressions, and the straight lines A and B can be obtained using these. And
Using the straight lines A and B, an optimum combination range of D and H can be determined. The range that can be interpolated by the above-described quadratic expression is that the effective diameter L of the target is in the range of 101 to 216 mm.
There is no problem even in the range of 0 mm. This is the same for FIGS.

Similar curve interpolation can be performed for other substrate sizes. FIG. 20 shows the substrate diameter d = 100 m.
20 is a graph similar to FIG. 19 for m. The quadratic expression when the curve is interpolated is as follows. Aa = −3.340E-5L ² + 7.022E-3L + 6.315E-1 Ab = 7.885E-3L ² −1.465L + 1.475E + 2 Ba = −2.913E-5L ² + 5.062E-3L + 1.236Bb = 8.886E -3L ² -1.645L + 1.137E + 2

FIG. 21 is a graph similar to FIG. 19 for a substrate diameter d = 125 mm. The linear expression when the straight line is approximated is as follows. Aa = −3.921E-5L ² + 9.388E-3L + 4.519E-1 Ab = 9.506E-3L ² −2.074L + 2.025E + 2 Ba = −4.661E-5L ² + 8.775E-3L + 1.079 Bb = 1.045E -2L ² -1.929L + 1.181E + 2

FIG. 22 is a graph similar to FIG. 19 for a substrate diameter d = 150 mm. The linear expression when the straight line is approximated is as follows. Aa = −2.703E-5L ² + 5.699E-3L + 7.002E-1 Ab = 6.867E-3L ² −1.284L + 1.596E + 2 Ba = −5.001E-7L ² −4.276E-3L + 2.027 Bb = 4.352E -3L ² -1.006E-1L-2.432E + 1

Finally, a description will be given of the “adhesion efficiency” that frequently appears in this specification. The deposition efficiency refers to the ratio of “the amount of sputtered particles deposited on the substrate” to “the total amount of sputtered particles released from the target”. This will be described with reference to FIG. The sputtered particles emitted from the target 10 show an adhesion density (the amount of adhesion per unit area) like a curved surface 40 on a plane separated by a distance H from the target 10. The total volume under the curved surface 40 corresponds to the total amount of sputtered particles. On the other hand, the volume of the shaded area above the circular substrate 12 corresponds to the amount of sputtered particles attached to the substrate 12. If there are a plurality of substrates 12, the total thereof is the amount of sputtered particles adhering to the substrates. Note that the thickness of the region 42 is averaged by the rotation of the substrate 12.

[0043]

According to the sputtering apparatus of the present invention, the relationship between the diameter D of the revolving orbit and the distance H between the target and the substrate is obtained by using a substrate holder device for revolving five or six substrates according to the substrate size. Is set in a predetermined relationship, without increasing the target size too much, and without increasing the distance between the target and the substrate, ±
A very good film thickness distribution of 0.5% or less is obtained, and the film deposition speed and the deposition efficiency are also improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a positional relationship between a target and a substrate in one embodiment of a sputtering apparatus of the present invention.

FIG. 2 is a front sectional view of one embodiment of the sputtering apparatus of the present invention.

FIG. 3 is a plan view of the substrate holder device.

FIG. 4 is a graph of a simulation result of a numerical value of a film thickness distribution.

FIG. 5 shows a film thickness distribution when a film is actually formed by contour lines.

FIG. 6 is an explanatory diagram illustrating the definition of the adhesion efficiency.

FIG. 7 is a plan view showing an example of a substrate arrangement for each substrate size.

FIG. 8 is a graph similar to FIG. 4 when the diameter d of the substrate is 125 mm.

FIG. 9 is a graph similar to FIG. 4 when the diameter d of the substrate is 150 mm.

FIG. 10 is a graph obtained by linearly approximating a boundary of a hatched region in FIG. 4;

FIG. 11 is a graph obtained by linearly approximating a boundary of a hatched region in FIG. 8;

FIG. 12 is a graph obtained by linearly approximating a boundary of a hatched region in FIG. 9;

FIG. 13 is a graph similar to FIG. 4 when the diameter d of the substrate is 75 mm.

14 is a graph obtained by linearly approximating a boundary of a hatched region in FIG.

FIG. 15 is a sectional view showing an erosion shape of a target.

FIG. 16 is a plan view showing a substrate arrangement example when the diameter of the substrate is 75 mm.

FIG. 17 is a table showing the coordinates of the slope Aa and intercept Ab of the straight line A, the slope Ba and intercept Bb of the straight line B, and the intersection C for three target sizes for four types of substrate sizes.

FIG. 18 shows the slope Aa, intercept Ab, and straight line B of the straight line A.
Is a table showing coefficients of a quadratic equation of curve interpolation for obtaining the slope Ba and intercept Bb of the target from the effective diameter L of the target.

FIG. 19 shows Aa when the diameter d of the substrate is 75 mm,
It is a graph which shows curve interpolation of Ab, Ba, and Bb.

FIG. 20 shows A when the diameter d of the substrate is 100 mm.
It is a graph which shows curve interpolation of a, Ab, Ba, and Bb.

FIG. 21 shows A when the diameter d of the substrate is 125 mm.
It is a graph which shows curve interpolation of a, Ab, Ba, and Bb.

FIG. 22 shows A when the diameter d of the substrate is 150 mm.
It is a graph which shows curve interpolation of a, Ab, Ba, and Bb.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Target 12 Substrate 14 Substrate holder device 16 Vacuum container 18 Cathode 20 Magnet unit 22 Pallet 24 Substrate holder 26 Large gear 28 Small gear 38 Revolution orbit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Tomoko Matsuda, Inventor 5-8-1, Yotsuya, Fuchu-shi, Tokyo Inside Anelva Co., Ltd. (72) Kazuo Hirata 5-81-1, Yotsuya, Fuchu-shi, Tokyo Anelva Inside the corporation

Claims (4)

[Claims] 1. A sputtering apparatus having a circular target and a revolving substrate holder apparatus, the sputtering apparatus having the following features. (A) The self-revolving substrate holder device includes five circular substrate holders, each of which revolves such that the center thereof passes through a circular orbit, and
Each of the substrate holders rotates around its own center. (B) The five substrate holders are arranged at equal intervals along the orbit. (C) The substrate holding surface of each substrate holder is parallel to the surface of the target. (D) When viewed from a direction perpendicular to the target, the center position of the orbit coincides with the center position of the target. (E) The effective diameter L of the target is 100 to 220 m
m. (F) Each of the substrate holders can hold one substantially circular substrate having a diameter of 100 mm. (G) Assuming that the distance between the target and the substrate is H (unit is mm) and the diameter of the orbit is D (unit is mm), a coordinate space in which H and D are taken on two orthogonal coordinate axes is given by D
And H exist in an area surrounded by the following three straight lines (a) to (c). (B) D = Aa × H + Ab (b) D = Ba × H + Bb (c) H = 160 (h) Slope Aa and intercept Ab in the straight line of (a)
And the slope Ba and the intercept Bb in the straight line (b).
Is calculated by the following (d) to (g) using the effective diameter L (unit: mm) of the target. (D) Aa = −3.340E-5L ² + 7.022E-3L + 6.315E-1 (e) Ab = 7.885E-3L ² −1.465L + 1.475E + 2 (f) Ba = −2.913E-5L ² +5. 062E-3L + 1.236 ^{(door) Bb = 8.886E-3L 2 -1.645L} + 1.137E + 2 2. A sputtering apparatus having a circular target and a revolving substrate holder apparatus, the sputtering apparatus having the following features. (A) The self-revolving substrate holder device includes five circular substrate holders, each of which revolves such that the center thereof passes through a circular orbit, and
Each of the substrate holders rotates around its own center. (B) The five substrate holders are arranged at equal intervals along the orbit. (C) The substrate holding surface of each substrate holder is parallel to the surface of the target. (D) When viewed from a direction perpendicular to the target, the center position of the orbit coincides with the center position of the target. (E) The effective diameter L of the target is 100 to 220 m
m. (F) Each of the substrate holders can hold one substantially circular substrate having a diameter of 125 mm. (G) Assuming that the distance between the target and the substrate is H (unit is mm) and the diameter of the orbit is D (unit is mm), a coordinate space in which H and D are taken on two orthogonal coordinate axes is given by D
And H exist in an area surrounded by the following three straight lines (a) to (c). (B) D = Aa × H + Ab (b) D = Ba × H + Bb (c) H = 160 (h) Slope Aa and intercept Ab in the straight line of (a)
And the slope Ba and the intercept Bb in the straight line (b).
Is calculated by the following (d) to (g) using the effective diameter L (unit: mm) of the target. (D) Aa = −3.921E-5L ² + 9.388E-3L + 4.519E-1 (e) Ab = 9.506E-3L ² −2.074L + 2.025E + 2 (f) Ba = −4.661E-5L ² +8. 775E-3L + 1.079 ^{(door) Bb = 1.045E-2L 2 -1.929L} + 1.181E + 2 3. A sputtering apparatus comprising a circular target and a revolving substrate holder apparatus, the sputtering apparatus having the following features. (A) The self-revolving substrate holder device includes five circular substrate holders, each of which revolves such that the center thereof passes through a circular orbit, and
Each of the substrate holders rotates around its own center. (B) The five substrate holders are arranged at equal intervals along the orbit. (C) The substrate holding surface of each substrate holder is parallel to the surface of the target. (D) When viewed from a direction perpendicular to the target, the center position of the orbit coincides with the center position of the target. (E) The effective diameter L of the target is 100 to 220 m
m. (F) Each of the substrate holders can hold one substantially circular substrate having a diameter of 150 mm. (G) Assuming that the distance between the target and the substrate is H (unit is mm) and the diameter of the orbit is D (unit is mm), a coordinate space in which H and D are taken on two orthogonal coordinate axes is given by D
And H exist in an area surrounded by the following three straight lines (a) to (c). (B) D = Aa × H + Ab (b) D = Ba × H + Bb (c) H = 160 (h) Slope Aa and intercept Ab in the straight line of (a)
And the slope Ba and the intercept Bb in the straight line (b).
Is calculated by the following (d) to (g) using the effective diameter L (unit: mm) of the target. (D) Aa = -2.703E-5L ² + 5.699E-3L + 7.002E-1 (e) Ab = 6.867E-3L ² -1.284L + 1.596E + 2 (f) Ba = −5.001E-7L ² −4.276 E-3L + 2.027 (g) Bb = 4.352E-3L ² −1.006E-1L−2.432E + 1 4. A sputtering apparatus having a circular target and a revolving substrate holder apparatus, the sputtering apparatus having the following features. (A) The self-revolving substrate holder device includes six circular substrate holders, each of which revolves such that the center thereof passes through a circular orbit, and
Each of the substrate holders rotates around its own center. (B) The six substrate holders are arranged at equal intervals along the orbit. (C) The substrate holding surface of each substrate holder is parallel to the surface of the target. (D) When viewed from a direction perpendicular to the target, the center position of the orbit coincides with the center position of the target. (E) The effective diameter L of the target is 100 to 220 m
m. (F) Each of the substrate holders can hold one substantially circular substrate having a diameter of 75 mm. (G) Assuming that the distance between the target and the substrate is H (unit is mm) and the diameter of the orbit is D (unit is mm), a coordinate space in which H and D are taken on two orthogonal coordinate axes is given by D
And H exist in an area surrounded by the following three straight lines (a) to (c). (B) D = Aa × H + Ab (b) D = Ba × H + Bb (c) H = 160 (h) Slope Aa and intercept Ab in the straight line of (a)
And the slope Ba and the intercept Bb in the straight line (b).
Is calculated by the following (d) to (g) using the effective diameter L (unit: mm) of the target. ^{(D) Aa = -2.440E-5L 2 +} 3.995E-3L + 7.254E-1 ( ^{e) Ab = 7.915E-3L 2 -1.476L} + 1.525E + 2 ( f) Ba = 3.116E-5L ² -1.457E -2L + 2.694 ^{(DOO) Bb = 3.172E-3L 2 +} 1.822E-1L-1.536E + 1