JPH043926A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To prevent the peeling of a metallic layer at a time when the high melting-point metallic layer is formed to a substrate by forming an adhesive layer so that the whole outer circumferential section of the substrate is extruded from a substrate base plate and also forming an adhesion layer around a second main surface. CONSTITUTION:When a substrate 1 is placed under the state, in which the whole outer circumferential section of the substrate is extruded from the outer circumference of a substrate table 2, and an adhesive layer 3 is formed, structure in which the adhesive layer is shaped on the whole surface of the substrate 1 is obtained while an adhesive layer is also formed on the rear as a second main surface 12 in the extruded section 1a of the substrate 1. A high melting- point metallic layer is formed on the whole surface on the adhesive layer 3 acquired through a blanket CVD method. Consequently, even when a high melting-point metal creeps and adheres on the rear of the substrate 1, there is the creeping and shaped adhesive layer section 3a on the rear previously, thus generating no peeling of the high melting-point metallic layer. Accordingly, the generation of the peel ing of the high melting-point metallic layer can be prevented, thus excellently shaping the high melting-point metallic layer.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

Industrial application field Outline of the invention Conventional technology Problems to be solved by the invention Examples of means and effects for solving the problems Example-1 Example-2 Example-3 Example-4 Example- 5 Example-6 Effects of the Invention [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a method for manufacturing a semiconductor device including a high melting point metal layer. In the present invention, for example, a tungsten (hereinafter also referred to as W as appropriate) layer is formed as a high melting point metal layer,
This can be used when manufacturing a semiconductor device using this as wiring.

[Summary of the invention]

Each of the inventions of the present application prevents the metal layer from peeling off as described below when manufacturing a semiconductor device by forming a high melting point metal layer on a substrate.

That is, the invention of claim 1.2 forms the adhesive layer so that the entire outer peripheral part of the substrate protrudes from the substrate mounting table, so that the adhesive layer is also formed around the second main surface (back surface), This prevents the high melting point metal from peeling off from there even if it is formed around the second main surface.

According to the third aspect of the invention, by forming an adhesion layer using an electrostatic chuck means and grounding the protruding peripheral portion of the substrate, no adhesion layer is formed on the gripping portion when the substrate is supported or grounded by mechanical gripping. This prevents the high melting point metal layer from peeling off from that part.

The invention of claim 4 prevents the high melting point metal layer from peeling off from that part due to not forming the adhesive layer when the substrate is mechanically gripped by forming the adhesive layer in a face-up state. , the problem of particle contamination is solved by forming a high melting point metal layer in a face-down state.

The invention as claimed in claim 5 provides good adhesion and low resistance by filling the connection hole with a high melting point metal by selective CVD and then sputter etching to form an adhesion layer and a high melting point metal layer thereon. This allows a high melting point metal layer to be formed.

According to the sixth aspect of the invention, a portion of the high melting point metal layer that is likely to be peeled off is removed by etching to prevent peeling from that portion.

[Prior Art] In the field of semiconductor devices, there is a remarkable trend toward miniaturization and integration. As the integration of semiconductor devices progresses,
The width of wiring formed in semiconductor devices is also becoming narrower. As the wiring width becomes smaller, conventional wiring materials such as A! (Aluminum) wiring may cause reliability problems. For this reason, high melting point metals such as W, which are said to have higher reliability than A2, are required to solve the problem.

High melting point metals such as W are also preferable in terms of heat resistance.

When using a high melting point metal, particularly W, as a wiring material, it is preferable to use a blanket W-CVD method to form W into a film. The blanket W-CVD method is a technique in which W is coated over the entire portion that requires film formation, and then patterned, and W can be formed into a film with low resistivity. For example, compared to the sputtering method, the resistance is low at 10 μΩ/cm or less, and the step coverage is also good, reaching about 90%. Hereinafter, W formed by the blanket W-CVD method may be abbreviated as BLK-W as appropriate. Regarding this type of technology, for example, Japanese Patent Application Laid-Open No. 62-21994
It is stated in No. 5.

[Problem that the invention seeks to solve]

However, the Planchera t-CVD method has major problems that need to be solved. One is the problem of BLKW adhesion. In general, the CVD method has poorer adhesion of W than the sputtering method. In order to improve the adhesion of BLK-W, a technique is known in which a thin film of TiN or sputtered W is formed on the base and used as an adhesion layer. Since the wafer on which the layer is to be formed is generally held down with a clip, the TiN film is not formed under the clip, and the adhesion of BLK-W in that area becomes poor. For example, as schematically shown in FIG. 8(a),
A wafer a (consisting of a Si substrate portion a2 and a Si substrate portion a1 thereon as shown in FIG. 8(b)), which is a substrate, is held by a clip b, and no adhesive layer is formed on this portion. As shown in Figure 8(b), add BLK on top of this.
- When the W layer e is formed, the BLK-W is likely to peel off from the Sin part of the wafer a and the part d where the adhesion layer C is not present in the part a1.

Another problem is that BLK-W has a relatively high temperature (500
Since the BLK-W film is formed at a temperature of 0.1 C or higher, the BLK-W easily spreads not only to the necessary surface of the wafer as a substrate but also to the back surface of the wafer. BLK-W that goes around the back side is TiN
Since it is not attached to the back side, it is formed in a state where it easily peels off. Therefore, BLK-W peels off from the back surface, and the peeling continues to BLK-W on the front surface.

Yet another problem is the generation of particles. BLK-W generally uses a 5iHa source and uses a 58
Since the film is formed at the 0 position, particles are likely to be generated due to vapor phase nuclear growth.

It is an object of each invention of the present application to provide a means for solving the above-mentioned problems and forming a high melting point metal layer in a good manner. That is, a method for manufacturing a semiconductor device that does not cause peeling of the high melting point metal layer and can form the high melting point metal layer well, or furthermore, can form a high melting point metal layer that does not cause peeling and does not generate particles. The purpose of the present invention is to provide a method for manufacturing a semiconductor device.

[Means and effects for solving the problem 3 The invention of claim 1 of the present application is a method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, is placed on a substrate mounting table with its entire outer periphery protruding from the outer periphery. and a second step of forming a high melting point metal layer by blanket CVD.

As a result of this configuration, an adhesive layer is formed not only on the first principal surface of the substrate but also on the peripheral portion of the second principal surface on the entire outer circumference of the substrate that protrudes from the outer circumference of the substrate mounting table. Therefore, the next formed high melting point metal layer is temporarily
Even if the adhesive is formed around the main surface of the second main surface, it is prevented from peeling off from the second main surface.

The invention according to claim 2 of the present application is the method for manufacturing a semiconductor device according to claim 1, characterized in that the entire outer periphery of the substrate is heated to a higher temperature than the inner periphery of the substrate.

As a result of bringing the outer circumferential portion of the substrate into a high temperature state in this manner, the above-mentioned effect can be made more pronounced.

The invention according to claim 3 of the present application is a method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, wherein a substrate mounting table supporting the substrate has an electrostatic chuck means. and placing the substrate with the entire outer circumference protruding from the outer circumference of the electrostatic chuck means, and at least a part of the second main surface at the outer circumference of the substrate protruding from the electrostatic chuck means. a first adhesive layer forming an adhesive layer over at least the entire first main surface of the substrate in a grounded state;
and a second step of forming a high melting point metal layer over the entire surface of the adhesive layer by blanket CVD.

As a result of this configuration, there is no need to mechanically hold and support the board itself with a clip or the like, or to ground it, and therefore the high melting point metal layer from there does not form an adhesive layer at the clip part due to gripping. It can solve the problem of peeling.

The invention according to claim 4 of the present application is a method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the first main surface of the substrate being in a face-up state. A first step of forming an adhesive layer on at least the entire first main surface of the substrate is performed, and then, the first main surface of the substrate is placed face-down on the entire surface of the adhesive layer. This method is characterized by performing a second step of forming a melting point metal layer by a blanket CVD method.

As a result of this configuration, the adhesive layer is formed on the board when it is face-up, so there is no need to mechanically hold and support it with clips, etc. This can prevent the problem of peeling off of the high melting point metal layer. Furthermore, since the high melting point metal layer is formed face down, the problem of particles on the first main surface can be prevented.

The invention of claim 5 of the present application is a method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the method comprising: forming a connection formed on a first main surface of the substrate; After performing selective CVD of a high melting point metal inside the hole, at least the surface of the high melting point metal formed by the selective CVD is sputter etched using a rare gas, and continuously, a small amount (all over the first main surface of the substrate) is etched. A first step of forming an adhesive layer;
Blanket CV coating of high melting point metal layer on the entire surface of the adhesive layer
A second step of forming by method D is performed.

As a result of this configuration, since the surface of the selected high melting point metal CVD is treated by sputter etching, an adhesion layer can be formed thereon with low resistance. A high melting point metal layer can be formed by CVD.

The invention according to claim 6 of the present application is a method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the method comprising: clamping at least a part of the outer circumference of the substrate on a substrate mounting table; forming an adhesive layer on the first main surface of the substrate, forming a high melting point metal layer on at least the entire surface of the adhesive layer; The method includes the step of etching the outer peripheral portion of the main surface and the second main surface of the substrate to expose the surface of the substrate.

As a result of this configuration, the high melting point metal layer can be formed by etching the metal layer formed around the substrate.
Even if the adhesive layer is not formed on the clamp contact portion, the high melting point metal in that portion is removed, and therefore, peeling of the high melting point metal layer from this portion can be prevented.

〔Example〕

Examples of the present invention will be described below. However, it goes without saying that the present invention is not limited to the examples shown below.

Example-1 This example embodies the invention of claim 1 of the present application,
This invention is applied to the case of forming W wiring in a semiconductor integrated circuit device. This semiconductor device is, for example, S
It can be used as RAM.

In this embodiment, as shown in FIG. 1, a substrate 1 on which W wiring is to be formed is placed with its entire outer periphery protruding from the outer periphery of a substrate mounting table 2.

The part of the board 1 protruding from the board mounting table 2 is designated by reference numeral 1a.
Indicated by

In this state, the adhesive layer 3 is formed on the substrate 1.

This provides a structure in which the entire surface (principal surface) of the substrate 1 is provided with an adhesive layer. Further, at the same time, in the protruding portion 1a of the substrate 1, the second main surface 1 of the substrate 1
An adhesion layer is also formed on the back surface (No. 2). The adhesive layer portion formed around the back surface is indicated by reference numeral 3a.

A high melting point metal layer is formed on the entire surface of the adhesive layer 3 obtained above by blanket CVD.

In this way, even if the high melting point metal wraps around and adheres to the back surface of the substrate 1, there is already an adhesion layer portion 3a formed by wrapping around there, so the high melting point metal layer can be removed from here. No peeling occurs.

In this embodiment, more specifically, the adhesive layer 3 is made of TiN.
(Titanium nitride) and is formed by bias ECR-CVD method.

The detailed steps of this example are as follows.

First, a semiconductor wafer, which is the substrate 1 on which the high melting point metal layer 3 in this embodiment is to be formed, is attached to a susceptor smaller in diameter than the wafer as the substrate mounting body 2 using an electrostatic chuck. In this example, since an electrostatic chuck can be used in this way, it is possible to take measures against dust (particles, etc.).

The adhesion layer was formed by CVD of TiN under the following conditions.

Gas used: TiC1a/NH3/(Hz)/Ar =10/10/
(100)/40 SCCM (hydrogen in parentheses does not need to be used) pressure crab 5 xio-” T
orr Microwave: 800W RF: 300W The bias ECR-CVD method does not require heating, so there is no need to use a susceptor with a built-in heater.

At this time, as shown in FIG. 1, the reactive species spread to the back surface of the wafer (substrate 1) (the surface of two examples of substrate mounting tables).

In Fig. 1, the plasma flow is indicated by an arrow, and as shown in the figure, the reactive species go around to the back surface of the wafer, which is the substrate 1, along the plasma flow. TiN is attached.

Next, BLK-W as a high melting point metal is subjected to CVD under well-known conditions. Of course, this CVD can also be performed using a continuous chamber.

During this CVD0, even if the BLK-W goes around to the back side a little, the BLK-W will not be peeled off.

For example, the following conditions can be employed for forming BLK-W.

Pressure Crab 0.1~50Torr Gas used:
WFs/5iH4=20/30 (gas ratio) temperature
degree: 375 to 500 ''C According to this example, since the adhesive layer 3 was also formed on the periphery of the back side of the substrate 1, it was possible to prevent the BLK-W from peeling off from the back side, thus achieving good adhesion. A high-melting point metal (W in this case) layer can be formed. Also, in this example, since the TiN layer, which is the adhesion layer 3, is formed by bias ECR-CVD, a good adhesion layer 3 can be formed efficiently.

Example-2 This example embodies the invention of claim 2 of the present application,
Similar to Example 1, this example is for forming W wiring in a semiconductor integrated circuit device.

In this embodiment, as shown in FIG. 2, the substrate 1 is placed with its entire outer periphery 1a protruding from the outer periphery of the substrate mounting table 2, and the entire outer periphery 1a of the substrate is placed inside the substrate. The temperature is higher than that of the peripheral portion (the portion of the substrate 1 that is inside the outer peripheral portion 1a). Specifically, in this example, a heating means (heater, etc.) built into a susceptor that constitutes the substrate mounting table 2 is used.
41 was used to generate this high temperature state.

More specifically, this embodiment is a case where the above invention is applied to a sputtering apparatus, and as shown in FIG. is buried and heated to, for example, 300° C. or higher using this heater 2. In FIG. 2, the flow of heat for heating is schematically indicated by arrow H.

In this state, a TiN layer is formed using a sputtering method, and this is used as the adhesive layer 3. In this case, TiN is sputtered and blown away due to heating.
causes thermal migration and wraps around the back surface (second main surface 12) of the wafer, which is the substrate 1, and the TiN
is deposited.

As a result, an adhesion layer made of TiN is well formed around the back side of the substrate 1 as well. In the figure, the reactive species are schematically indicated by the symbol R. In addition, the flow of reactive species is schematically shown with arrows.

Sputtering conditions for forming the TiN layer, which is the adhesive layer, can be set as follows, for example.

DC power: 6kW Gas used and flow rate: A r =72SCCM, N
z = 28SCCM applied RF bias: 400
V Temperature condition = 300°C heating (back side of wafer) As a result of the adhesion layer made of TiN being formed around the back side of the wafer, which is the substrate 1, next, blanket CVD was performed.
When a film of a high melting point metal such as W is formed by a method,
Even if W is formed around the back surface of the base vil, the W is prevented from peeling off from the back surface.

In the above example, the heater 41 built into the substrate mounting table 2 was used to heat the entire outer periphery of the wafer, which is the substrate 1, to a higher temperature than the inner periphery, but a lamp may also be used for this heating. do not have. Even when using indirect heating means such as a lamp, the flow of heat may be as schematically shown by arrow H. Any other means may be used to make the entire outer circumference of the substrate 1 higher in temperature than the inner circumference.

In addition, the built-in heater is not only the surrounding heater 41,
It may also be arranged in the center of the substrate mounting table 2 (for example, the illustrated heater 42) to heat the entire substrate while keeping the outer circumference of the substrate 1 at a higher temperature than the inner circumference.

Although the above configuration example embodies the invention of claim 2 using a sputtering apparatus, the invention can also be easily applied to a CVD apparatus.

In this case, for example, CVD is performed using the wafer susceptor, which is the substrate mounting table 2 shown in FIG.
An adhesion layer made of iN is formed.

The CVD conditions can be set as follows, for example.

Gas system used: T1Cf a/NHz/Hz/(Nz)
=100/100/1000/ (200) SCC
M (Nitrogen in parentheses does not have to be used) CVD temperature conditions: 500-750°C Pressure
: 0.1 to 50 Torr Also in this case, it goes without saying that the entire outer periphery of the wafer, which is the substrate 1, is kept at a higher temperature than the inner periphery using the heater 41 or the like.

As a result, the same effect as the above-mentioned sputtering method can be obtained.

Example 3 Next, Example 3 will be described. This embodiment embodies the invention of claim 3 of the present application. In particular, when forming an adhesion layer by the conventional sputtering method, the wafer, which is the substrate 1, is fixed to the opposite surface of the target with a clip. Tame (8th
(See Figure (a)), the part held by the clip remains as a clip mark, and no adhesive layer is formed there, so the high melting point metal film such as W formed on it will peel off from this clip mark. (Chapter 8)
(see Figure (b)) is solved by providing an electrostatic chuck means.

In this example, as shown in FIG. 3, the substrate mounting table 2 that supports the substrate 1 has an electrostatic chuck means 5. In this example, as shown in FIG. 5), and at least a part of the second main surface 12 of the substrate 1 is grounded at the substrate outer peripheral portion 1a protruding from the electrostatic chuck means 5, and in this state, T is applied by sputtering or the like.
Deposit iN. This forms an adhesive layer.

For example, a part or all of the area of the substrate mounting table 2 that is not used as the electrostatic chuck means 5 is grounded so that the sputtering charge flows through the ground. In the illustrated example, the periphery of the wafer, which is the substrate 1, is grounded in a ring shape. This ring-shaped earth connection part (earth electrode)
is indicated by 6. It may be formed into a comb shape instead of a ring shape.

The shape is arbitrary.

As described above, in the substrate outer peripheral portion 1a protruding from the electrostatic chuck means 5, the second main surface 12 of the substrate 1, that is, the side opposite to the surface on which a high melting point metal layer such as W is to be formed in a later step. Since at least a part of the back surface, which is the surface of the electrostatic chuck means 5, is grounded, the charge such as Ar'' generated by sputtering is grounded in part or all of the part 1a protruding from the electrostatic chuck means 5. Therefore, by supporting with the electrostatic chuck means 5, it is possible to eliminate the need for holding and supporting with a clip as in the conventional case.
Moreover, due to the above grounding, there is no need to use a clip to connect the ground (therefore, in principle, no clip marks will occur,
An adhesion layer is well formed on at least the entire first main surface 11 including the peripheral portion of the substrate 1 . Therefore, if BLK-W is formed by the CVD method after this, the W from the clip mark
No peeling occurs.

The above description has been made of the case where the substrate 1 is not biased and no bias control is particularly required, but it is also possible to carry out the process by applying a bias to the substrate 1. for example,
It is possible to apply a reverse bias to neutralize the Ar'' charge. When applying a bias, it is sufficient to turn on the power to the ground wiring section as shown in parentheses in the figure and indicated by the reference numeral 61. This power supply may be an RF high frequency power source or a DC direct current power source. Usually, a DC direct current power source is used.

In FIG. 3, 62 is a target for sputtering, 6
3 is an anode. Further, β and ε indicate the direction of current and magnetic field for magnetron sputtering, respectively.

What is shown in FIG. 4 is a modification of the above example, which also embodies the invention of claim 3, but in this example, a multi-electrode (two or more) electrostatic capacitor is mounted on the substrate mounting table 2. It uses a chuck. In the figure, two sets of electrostatic chuck means having a charge of ee (indicated by reference numerals 51 and 52) are shown, but a larger number may be provided.

V, ,V, are variable power supplies, which may also be provided in corresponding numbers.

In this example, the charge may be generated in a part of the wafer, which is the substrate 1, so that a partially opposite charge is accumulated and attached to the electrode. Furthermore, when removing the substrate 1 from the electrostatic chuck means 51, 52, it can be removed at the same potential or at slightly opposite potentials.

A reverse bias may be applied only to parts that are difficult to peel off.

This configuration also eliminates the need for gripping or grounding clips on the board 1, so the conventional problems are solved.

Although the above description is based on an example in which the invention of claim 3 is applied to sputtering, it can also be applied to a bias ECR-CVD method or a bias-plasma-CVD method in which a bias is applied.

In this case, charges generated in the electrostatic chuck on the surface of the substrate 1 can be canceled out within the substrate 1. Furthermore, by turning on a bias power source to the ground electrode section, a bias can be applied regardless of the electrostatic potential.

Example 4 This example embodies the invention of claim 4 of the present application. According to this example, there are problems with the deterioration of adhesion of high melting point metals such as W due to not forming an adhesion layer due to clips etc. for supporting the substrate 1, and vapor phase nuclear growth when using an S+84 source. This can also solve the problem of particle generation due to

In this example, after performing the first step of forming an adhesive layer over the entire first main surface with the first main surface of the substrate facing up, the first main surface of the substrate is A second step of forming a high melting point metal layer on the adhesive layer is performed with the surface facing down.

Specifically, when depositing and forming TiN as an adhesion layer, the film is formed face-up, and then the substrate or wafer is turned over and the BLK-W layer is deposited face-down as a high-melting point metal layer. To form a film.

For example, a wafer, which is a substrate, is transferred from a load chamber to a TiN chamber, and a TiN film is formed in a face-up state.

The conditions at this time are, for example, gas system: TiCl /NH3/H2/ (NZ) =
100/100/1000/ (200) SCCM(
(N, may be omitted) Temperature: 500 to 750°C Pressure: 0.1 to 0.5 Torr.

At this time, since the film is formed face-up, no crimp or the like is required for gripping, and TiN is applied to the entire surface.

Next, the substrate is connected to the continuous BLK through the gate valve.
- It is carried to a CVD chamber for W formation, and BLK-W is formed into a film. At this time, in the transfer system, the arm that grips the wafer, which is the substrate, is rotated half a turn, thereby inverting the substrate. As a result, the next process of forming a W layer is performed face down.

The BLK-W CVD conditions can be set, for example, as follows.

Gas system: Wh/SiH4 ratio = 20/3 specific pressure 20/30
Pressure - 50 Torr Temperature: 370 - 450°C The above temperature conditions are conditions in which particles are relatively easy to come out during CVD in the conventional case.

In this embodiment, since the film is deposited face down on the substrate, particles are less likely to adhere to it.

As described above, in this embodiment, a metal continuous CVD apparatus connected through a gate valve is used, and at this time, an apparatus equipped with a device for reversing the substrate when it is transported to a samurai house is used. TiN in the front stage and BL in the rear stage.
By forming a film of K-W, the first step is performed face-up and the second step is performed face-down, which allows continuous film formation of high melting point metal and an adhesive layer. Since TiN is applied to the entire surface of the board, BLK
- Peeling of W is suppressed. Furthermore, generation of particles during BLK-W formation can be suppressed.

Example 5 This example embodies the invention of claim 5 of the present application. This example solves the problem that the heat-resistant adhesive layer, such as the TiN layer, does not wrap around the back side of the substrate, making it easy for the high melting point metal layer such as BLK-W to peel off when it wraps around the back side. At the same time, an oxide film is likely to grow on the top surface of a selectively grown metal layer, such as a W layer formed by selective tungsten CVD (therefore, if BLK-W is formed on this, the contact resistance will increase). This problem can also be solved.

In this embodiment, a high melting point metal such as W is placed inside the connection hole formed on the first main surface of the substrate.

Selective CVD of Mo, Ti, these intermetallic compounds, etc.
After depositing a small amount of the high melting point metal (also formed by the selective CVD) using a rare gas, sputter etching is performed to continuously form an adhesive layer on at least the entire first main surface of the substrate. A first step of forming the adhesive layer and a second step of forming a high melting point metal layer over the entire surface of the adhesive layer by blanket CVD are performed.

Specifically, in this embodiment, first, the connection holes (contact holes, pier holes, etc.) on the first main surface of the substrate are filled by selective tungsten growth. Although the substrate material is arbitrary, silicon, aluminum, various silicides, and the like are suitable for selective W growth. Select W
For growth, selective W is grown in the connection hole in a selective W growth chamber under the following conditions.

Gas system used: WFi/5iH4=10/75CCM
Temperature: 260°C Pressure: 0.2 Torr Next, brie-etching is performed using Ar gas under the following conditions using a bias ECR-CVD apparatus.

Gas used: Ar=50SCCM Pressure Crab 5 Xl0-'TorrRF bias:
300 round microwave: 800 W (875 Gauss) This bias ECR-CVD removes the oxide film on the top surface of the selection W. Therefore, contact resistance becomes small.

Next, TiN is formed in the same chamber. The conditions are as follows.

Gas system used: TiCL /NH3=20/30SCC
M pressure: 5 If supported, TiN will also grow on the back surface of the substrate (see Examples 1 and 2).

Next, BLK-W is formed. The conditions were as follows.

Gas system used: SiH4/WF6・15/60SCCM
Temperature: 475°C Pressure: 80 Torr At this time, even if the BLK-W wraps around to the back side to some extent, peeling is prevented because the adhesive layer of TiN is attached thereto as well.

As mentioned above, in this example, after refilling (embedding) the connection hole using the selective W method, Ar pre-etching and forming a TiN layer as an adhesion layer are performed using the bias ECRCVD method, and then BLK- Since W is formed, BLK-
W has good adhesion (and can be formed with low contact resistance) due to natural oxide film growth after selective growth, selective W and BLK-W
Even if these steps are performed continuously, TiN cannot be formed, so a film cannot be formed).

Furthermore, if the adhesive layer is formed using a substrate mounting table smaller than the wafer (substrate), peeling of BLK-W (particularly peeling from the back surface) will not occur. Furthermore, in this example, BLK
- The heat resistance of W can be improved.

Example 6 Next, Example 6 will be described. This example embodies the invention of claim 6 of the present application. FIG. 5 shows the configuration of this embodiment.

The semiconductor device manufacturing method of this embodiment has a small (
A step of placing a part of the substrate tightly on the substrate mounting table 2 using a clamp (not shown) and forming an adhesive layer on the first main surface of the substrate, and a high melting point metal layer on at least the entire surface of the adhesive layer. and a step of exposing the surface of the substrate by etching, for example plasma etching using a rare gas, the outer peripheral portion of the first main surface of the substrate including the clamp contact portion and the second main surface of the substrate. This makes it possible to prevent the high melting point metal layer from peeling off even when the substrate 1 is supported by clamps.

In this example, first, TiN is used as an adhesive layer on the substrate 1.
Sputter. For example, it is formed with a film thickness of 1000 people.

Blanket tungsten is then deposited. For example, 5
Formed with a film thickness of 0,000 people.

The conditions for forming this BLK-W layer were set as follows, for example.

(1st step) Temperature: 475°C Pressure: 80 Torr Gas system used: WFi, /5iHa/Hz・25/15
/ OSCCM (2nd step) Temperature: 475°C Pressure: 80Torr Gas system used: WF6/SiH4/H2/6010/3
60 SCC Next, from the state shown by the broken line in FIG. 5, the substrate 1 is lifted from the mounting table 2 by the lift finger 7 as shown in the same figure, and brought close to the gas outlet 81 as shown in FIG. At this time, the peripheral portion of the substrate 1, which is a semiconductor wafer, is made to protrude outside the outer peripheral position of the gas outlet 81. The protruding portion is indicated by reference numeral 1a.

Etching is performed in this state. As a result, not only the entire surface of the second main surface 12 but also the peripheral portion of the first main surface 11 on which the BLK-W layer is formed are etched.

FIG. 5 shows how, after BLK-W deposition, the substrate 1 is lifted with the fingers 7 and the peripheral parts of the second main surface 1a (back surface) and the first main surface 11 (front surface) are etched. It shows. In the case of this embodiment, plasma is generated not only near the second main surface 12 but also around the substrate 1. In the figure, the plasma 82 is schematically shown with thin dots.

In the conventional technique, as shown in FIG. 7 and clearly shown in FIG. No plasma is generated on the entire outer surface of 1.

Therefore, the first main surface 11 of the substrate 1 is not etched. On the other hand, in the case of this embodiment, the peripheral portion 1a of the substrate 10
The air outlet 81 is configured so that only the portion excluding the gas outlet 81 approaches the gas outlet 81, thereby generating plasma around the substrate 1.

As a result, after blanket tungsten CVD, the tungsten deposited not only on the second main surface 12 (back surface) but also on the peripheral portion of the substrate 1 can be removed by etching, so the substrate 1 is clamped when forming the TiN film as the adhesive layer. This solves the problem of the blanket tungsten peeling off from the mark of the chestnut knob even if it is held with a nail (clip) or the like.

〔Effect of the invention〕

As described above, each of the inventions listed in the present order can form a high melting point metal layer on a substrate in a good manner, can prevent peeling of the high melting point metal layer, and can form a high melting point metal layer in a good manner. This method also has the effect that a high melting point metal layer can be formed without generating particles.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional configuration diagram for explaining Example-1,
FIG. 2 is a partial cross-sectional configuration diagram for explaining Example-2. FIG. 3 is a configuration diagram for explaining Example-3,
FIG. 4 is a configuration diagram for explaining a modification of the third embodiment. FIG. 5 is a block diagram for explaining the sixth embodiment, and FIGS. 6 and 7 show conventional examples for comparison with the sixth embodiment. FIGS. 8(a) and 8(b) are diagrams showing problems in the prior art. ■... Substrate, 2... Substrate mounting table, 11... First main surface, 12... Second main surface, 3... Adhesion layer.

Claims (6)

[Claims] 1. A method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the method comprising: placing the substrate with its entire outer periphery protruding from the outer periphery of a substrate mounting table; A first step of forming an adhesive layer over the entire first main surface of the substrate, and a second step of forming a high melting point metal layer over the entire surface of the adhesive layer by blanket CVD.
A method for manufacturing a semiconductor device, comprising the steps of: 2. 2. The method of manufacturing a semiconductor device according to claim 1, wherein the entire outer periphery of the substrate is heated to a higher temperature than the inner periphery of the substrate. 3. A method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the substrate mounting table supporting the substrate having an electrostatic chuck means,
and the substrate is placed with the entire outer periphery of the substrate protruding from the outer periphery of the electrostatic chuck means, and at least a portion of the second main surface of the outer periphery of the substrate that protrudes from the electrostatic chuck means is grounded. a first step of forming an adhesive layer on at least the entire first main surface of the substrate; and a blanket CV coating of a high melting point metal layer on the entire surface of the adhesive layer.
A method for manufacturing a semiconductor device, comprising: a second step of forming by method D. 4. A method of manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the method comprising: forming a semiconductor device with the first main surface of the substrate face up; A first step of forming an adhesive layer on the entire surface is performed, and then a high melting point metal layer is continuously applied to the entire surface of the adhesive layer with the first main surface of the substrate face down using a blanket CVD method. A method of manufacturing a semiconductor device, comprising performing a second step of forming the semiconductor device. 5. A method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the method comprising: forming a high melting point metal layer by selective CVD in a connection hole formed on a first main surface of the substrate; a first step of sputter etching at least the surface of the high melting point metal formed by the selective CVD using a rare gas, and continuously forming an adhesive layer over at least the entire first main surface of the substrate; Blanket CV coating of high melting point metal layer on the entire surface of the adhesive layer
A method for manufacturing a semiconductor device, characterized in that a second step of forming by method D is performed. 6. A method for manufacturing a semiconductor device formed by a manufacturing process including a step of forming a high melting point metal layer on a substrate, the method comprising: placing at least a part of the outer circumference of the substrate tightly on a substrate mounting table using a clamp; a step of forming an adhesive layer on the main surface of the substrate; a step of forming a high melting point metal layer on at least the entire surface of the adhesion layer; an outer peripheral portion of the first main surface of the substrate including the clamp contact portion;
and etching the second principal surface of the substrate to expose the surface of the substrate.