JPS6342368A - Sputtering device - Google Patents

Abstract

PURPOSE:To easily and efficiently form good-quality laminated films by juxtaposing plural sputtering targets on a rotating cylindrical body along the rotating direction and sputtering the targets while the targets are successively opposed to a substrate to be treated. CONSTITUTION:Plural pieces of the sputtering targets 7A-7H are juxtaposed on the cylindrical body 4 rotated by a shaft 5 in a vacuum vessel 1 along the rotating direction of the cylindrical body 4. The inside of the vacuum vessel 1 is maintained at a prescribed vacuum degree by an inert gas. The target 7A is first opposed to the substrate 8 to be treated and is sputtered by impressing independent DC electric power through a backing plate 6A from a power source. The cylindrical body 4 is rotated in the state of maintaining the atmosphere in the vacuum vessel 1 as it is to oppose the targets 7B-7H successively to the substrate 8 to be treated and the sputtering is executed by impressing the DC electric powers respectively independently to the targets upon ending of the sputtering of the target 7A. The adhesiveness between the films of the respective layers is thereby increase and the film quality is uniformized. The good-quality laminated films are thus formed.

Description

[Detailed Description of the Invention] [Summary] From a plurality of sputter targets arranged in line along the rotational direction on a rotating cylinder, each of the sputter targets is sequentially placed on an opposing substrate to be processed. With a sputtering device that sequentially sputters target materials, a high-quality laminated film with high adhesion strength between each layer and uniform film quality of each layer can be easily and efficiently formed.

[Industrial application field]

The present invention relates to a sputtering apparatus, and particularly to a sputtering apparatus using a rotational target feeding method, which is advantageous for forming multilayer films.

In semiconductor rcs that are highly integrated such as LSIs, the wiring width has been extremely reduced, and impurity doped regions have also become extremely shallow.

In order to increase the wiring strength in such a situation, for example, aluminum (AI)-silicon (Si) alloy (AI-1
%Si) film, titanium (Ti) film, and 1-1%Si film, or in the contact area with the impurity introduction region, impurities can be introduced by preventing the dissolution of Si into the AI. In order to prevent junction breakdown in the region, Ti-
A wiring pattern having a multilayer structure having a TiN-Al structure is used.

Formation of the above-mentioned multilayer film requires complicated steps and also tends to cause variations in film quality, so improvements in these areas are desired.

[Conventional technology]

Conventionally, a magnetron sputtering device using a single target material, which is normally used for forming a single-layer film, has been used to form the above-mentioned multilayer film.

FIG. 2 is a schematic side cross-sectional view showing the main parts of the magnetron sputtering apparatus. In the figure, 51 is a vacuum container that becomes an anode, 52 is a gas inlet, 53 is a vacuum exhaust port, 54 is a banking plate that is a cathode, and 55 5 is a sputtering target, 56 is a magnet for forming a magnetic field for plasma confinement, 57 is a rotating magnet support, 5 is an insulator packing, 59 is a substrate holding jig, 60 is a substrate to be processed, 61 is a deposited film, E is DC power supply, G
ND represents ground, and N and S represent magnetic poles.

Note that an impure active gas such as argon (Ar) is used as the atmospheric gas, and the gas pressure (degree of vacuum) in the vacuum container during sputtering is set to 5 x 10-' Torrf 1 degree.

When forming wiring layers of the multilayer film structure described above in a short order using a normal magnetron sputtering device with such a single target configuration, it is necessary to use a number of sputtering devices (sputter targets are Since it is difficult to maintain exactly the same atmospheric conditions in each device, the quality of each layer varies, making it impossible to obtain the desired wiring performance. Oxidation and contamination during transport between devices have caused problems such as reduced adhesion between coatings of each layer and increased wiring resistance.

[Problem that the invention seeks to solve]

The problems that the present invention aims to solve are the variations in film quality for each layer that occur when multiple conventional sputtering devices are used when forming wiring layers of a multilayer film structure, and the problems that occur during transport between devices. These problems include a decrease in the degree of adhesion between each open film and an increase in wiring resistance due to oxidation and contamination, and further problems such as an increase in the number of work steps and the area occupied by the device due to an increase in the number of devices used.

[Means for solving problems]

A plurality of subasota targets) (7A) to (7A) arranged in line along the direction of rotation on the cylinder (4) arranged in the vacuum container (1) and rotating around the shaft (5). 71
1), and the rotating cylinder (4) in the vacuum container (1)
) A substrate to be processed (8) is placed at a position where each of the plurality of sputter targets (7A) to (7H) on A plurality of sputter targets (78) to (7H) facing each other in sequence
This problem is solved by the sputtering apparatus according to the present invention, which sequentially sputters each target material.

[For production]

That is, the sputtering apparatus of the present invention has a plurality of sputter targets arranged side by side along the rotational direction on a cylinder rotating in a vacuum container, and each of the plurality of sputter targets is sequentially sputtered onto an opposing substrate to be processed. By sequentially spucking the target materials of Since the targets are placed in the same vacuum container, the sputtering atmosphere for each target material is maintained at the same level and in a good condition. Since there is no external transport, the film quality of each layer is good and uniform, which improves the performance of the wiring layer. There is no oxidation or contamination of the liquid film surface of each layer, which increases the adhesion strength between the eyebrows of each layer and reduces the wiring resistance. This can be reduced.

〔Example〕

The present invention will be specifically described below with reference to an internal plan view (a), an internal side view (bl), and a power supply circuit diagram (C1) of an embodiment of a sputtering apparatus according to the present invention schematically shown in FIG. do.

In Figure 1, 1 is a vacuum container made of a conductor such as stainless steel, 2 is a gas inlet, 3 is a vacuum exhaust port, A is an octagonal cylinder made of an insulator, and 5 is the rotation axis of the cylinder. ,6A
, 6B, 6C, 6D, 6E, 6F, 6G.

61 (are independent backing plates made of copper or the like and each having a cooling means (not shown) inside; 7A;
7B, 7C, 7D, 7E, 7F, 7G, 7
M is a sputtering target, 8 is a substrate to be processed that is supported at the same potential as the container by fixing means (not shown) on the surface of the container facing the sputtering target in sequence, 9 is a power supply wiring, 1
o is a contact terminal between the power supply wiring and the backing plate schematically shown, 11 is a rotary sliding switch that is interlocked with the rotating shaft of the cylinder and is grounded, 12A, 12B, 12C11
20, 12E, 12F, 12G, 12H are connection terminals to each power supply, C6, Ell, Ec, εo-, Et, E
r1 Eo and EH indicate DC power supplies having different voltages, and GND indicates grounding.

The sputtering method is magnetron sputtering.
For example, a magnet (not shown) having a structure similar to that of the conventional example is disposed on the back side of the backing plate.

During sputtering, for example, different target materials are used for the targets 7A to 7H, an inert gas such as Ar is introduced from the gas inlet 2, and the air is evacuated through the vacuum exhaust port 3 to form a vacuum chamber 1 of 5×10 − First, the target material is sputtered onto the substrate 8 to be processed from the target 7A facing the substrate 8 to be processed while maintaining a degree of vacuum at a level of about 100 psi.

At this time, independent DC power is applied to the target 7A from the power source E1 via the rotary and sliding terminal 11 interlocked with the rotating shaft 5 of the cylinder 4 and further via the banking plate 6A. Usually sputtering voltage is 100-500V, power is 1-10K
It is about W.

After sputtering target 78 material for a predetermined time,
While maintaining the atmosphere inside the vacuum container 1, the cylinder 4 is rotated to a position where the next target 7B faces the substrate 8 to be processed. The target 7B is sputtered for a predetermined period of time using DC power independently supplied from the power source E through the terminal 11 and the backing plate 6B, and the target material 7A already deposited on the substrate 8 to be processed is sputtered. A sputtered film of target material 7B is deposited on the film.

Similarly, the cylinder 4 is sequentially rotated until the next target faces the substrate 8 to be processed, and the targets 7C to 7H
Then, sputtering is performed by applying independent DC power from the corresponding power supplies EC-EH, and sputtered films of the respective target materials are successively deposited on the substrate 8 to be processed.

In this way, in the sputtering apparatus of the present invention, sputtered films of a plurality of target materials are successively deposited in a layered manner on the same substrate 8 to be processed while the inside of the vacuum container 1 is maintained at a constant and good vacuum atmosphere. Ru. Therefore, the quality of the sputtered films of each target material is maintained uniformly, and since the surface of each sputtered film is not oxidized or contaminated, the adhesion between the sputtered films stacked is good and strong. It will be done.

The sputtering time for each target, that is, the time for which the target and substrate to be processed are left facing each other, is determined by the sputtering rate to obtain good film quality and the required sputtered film thickness, but if conditions permit. For example, the operation will be easier if the sputtering time for each target is constant.

In the above embodiment, an example was explained in which the targets 7A to 711 are all made of different materials, but it is also possible to use a plurality of targets made of the same material.

For example, Al-1%Si alloy is used for targets 7A, 7B, and 7C, Ti is used for targets 7D and 7E, and targets 7F, 7G, and 7
Using Al-1%Si alloy for 11, target 7A,
1700 people/7B, 7C17F, 7G, 7H each
sputter at min, target 7D, 7E at 500
By sputtering at a rate of 5,100 people/min, the sputtering time for each target was kept constant at 1 minute:
A wiring layer of the aforementioned Al-1%Si alloy-Ti-AI-1%Si alloy having a film thickness ratio of 1000:5100 can be formed.

Furthermore, in the above embodiment, the number of substrates to be processed is one, but this is not limited to one. In addition to the one substrate to be processed, another substrate is placed opposite to another target. By arranging the substrates to be processed, it is possible to form laminated sputtered films of the same type on a plurality of substrates to be processed in the same batch.

Furthermore, by arranging a plurality of target rows on the same cylindrical body, an apparatus with even greater manufacturing capacity can be formed.

In the above embodiment, the cylinder was formed into a regular octagon, and eight targets were arranged on the surface of the cylinder along the direction of rotation, but the shape of the cylinder is limited to the above-mentioned octagon. Therefore, the number of cugettes arranged along the rotation direction is not limited to the above-mentioned eight. Further, the cylinder may be cylindrical.

〔Effect of the invention〕

As described above, according to the sputtering apparatus of the present invention, when forming a laminated film on a substrate to be processed, the same good vacuum atmosphere can be maintained in the same vacuum container without transporting the substrate to be processed between devices. It is possible to form a continuous layer in the interior.

Therefore, the quality of each laminated film is uniform.

Furthermore, since there are no oxide films or contaminants interposed between the coatings of each layer, the adhesion strength between the liquid films of each layer increases, and in the case of laminated wiring layers, electrical resistance is reduced and patterning properties are improved. I can figure it out.

[Brief explanation of drawings]

FIG. 1 is an internal plan view schematically showing an embodiment of the present invention (
a), internal side view (BL and power supply circuit diagram FCL), and Figure 2 are schematic side sectional views of a conventionally used magnetron sputtering device. In the figure, 1 is a vacuum vessel, 2 is a gas inlet, and 3 is a gas inlet. Vacuum exhaust port, 4 cylinders, 5 is the rotation axis of the cylinder, 6^, 6B, 6C, 60, 6E, 6F, 6G,
684! Bucking plate, 78, 78, 7C17D, 7E, 7F, 7G,
711 is a sputter target, 8 is a substrate to be processed, 9 is a power supply wiring, 10 is a contact terminal, 11 is a rotary slide switch, 12A, 12B, 12C, 120, 12E,
12F. 12G, 12+1 are connection terminals, EA, , E6, Ec, EDlEE, EFlEG,
El+ indicates DC power supply and GND indicates grounding.

Claims (1)

[Claims] A plurality of sputters arranged in line along the direction of rotation on a cylinder (4) arranged in a vacuum container (1) and rotating around an axis (5). Target (7A) ~ (7H)
A substrate to be processed (8) is arranged at a position where each of the plurality of sputter targets (7A) to (7H) on the rotating cylinder (4) in the vacuum container (1) sequentially faces each other. , a sputtering apparatus characterized in that each target material is sequentially sputtered onto the substrate to be processed (8) from a plurality of sputter targets (7A) to (7H) sequentially facing the substrate to be processed (8). .