JPH11307605A - Semiconductor manufacturing device and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor manufacturing device and method, capable of high precisely forming films in thickness close to a specified value on a base substance, as well as prevented from occurring avoiding the production of a large number of defective units. SOLUTION: Although SiO2 films are successively formed in chambers 16a-16d while being carried on a conveyer 14, the thickness to be formed in the chamber 16d is adjusted according to the thickness measured by a film thickness measuring equipment 17a. Accordingly, the SiO2 films close to the specific value can be finally formed. Furthermore, when the thickness measured by the film thickness measuring equipment 17a, 17b is out of a desired range, both the formation of the SiO2 films and the carrying of the semiconductor wafers are stopped, so that the production of a large number of defective units are prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor manufacturing apparatus and a semiconductor manufacturing method for forming a film on a substrate.

[0002]

2. Description of the Related Art In manufacturing a semiconductor device, various films are formed on a substrate by a CVD device, a sputtering device, a vacuum deposition device, or the like. For example, in order to form a SiO ₂ film on a semiconductor wafer by a normal pressure CVD apparatus, while transporting the semiconductor wafer by a belt conveyor, a plurality of injectors arranged above the belt conveyor transmit TEOS and O ₃ . A raw material gas is ejected at a predetermined flow rate, and an SiO ₂ film is sequentially formed to a desired thickness over the plurality of injectors.

Then, in order to determine whether or not the SiO ₂ film is formed to a desired thickness, after completion of the formation of the SiO ₂ film, it is monitored by a film thickness measuring device separate from the normal pressure CVD device. A semiconductor wafer for monitoring was loaded, and the thickness of the SiO ₂ film formed on the semiconductor wafer for monitoring was measured by this film thickness measuring device.

[0004]

However, in the conventional atmospheric pressure CVD apparatus, once the flow rate of the raw material gas ejected from the injector is set before the SiO ₂ film is formed, the flow rate is adjusted until after the SiO ₂ film is formed. , Could not be changed. For this reason, the set flow rate was not accurate, so that a SiO ₂ film of a desired thickness could not be formed, or the ratio between TEOS and O ₃ was not accurate, so that a uniform in-plane In some cases, a thick SiO ₂ film could not be formed.

After the formation of the SiO ₂ film is completed,
Since the thickness of the SiO ₂ film of the semiconductor wafer for monitoring was measured, it was difficult to prevent a large number of defective products from occurring. For these reasons, it has been difficult to manufacture semiconductor devices with a high yield. Further, after the formation of the SiO ₂ film is completed, since the atmospheric pressure CVD apparatus was measured thickness of the SiO ₂ film of a semiconductor wafer for monitoring a separate film thickness measuring apparatus, the formation of the SiO ₂ film The time required is long and the burden on the operator is large, making it difficult to manufacture the semiconductor device at low cost.

[0006] The above-mentioned problem is caused by the CV other than the normal pressure CVD apparatus.
The same applies to a D apparatus, a sputtering apparatus, a vacuum evaporation apparatus, and the like. Therefore, according to the invention of the present application, a film having a thickness close to a desired value is formed with high precision on a base and the occurrence of a large number of defective products is prevented beforehand, so that a semiconductor device can be manufactured with a high yield. It is another object of the present invention to provide a semiconductor manufacturing apparatus and a semiconductor manufacturing method capable of manufacturing a semiconductor device at low cost because the time required for forming a film is short and the burden on an operator is small.

[0007]

In the semiconductor manufacturing apparatus according to the present invention, a film is sequentially formed on a substrate in a thickness direction by a plurality of film forming means while the substrate is conveyed by a conveying means.
The control means adjusts the thickness of the film to be formed by the film forming means after this measurement based on the film thickness measured by the film thickness measuring means. For this reason, even if the thickness of the formed film is different from the desired value halfway, a film having a thickness close to the desired value is finally formed on the substrate with high accuracy.

If the thickness of the film measured by the first or second film thickness measuring means is out of the desired range, the control means controls the formation of the film by the film forming means and the transport of the substrate by the transport means. Since the film is stopped, even if a film having a thickness outside the desired range is formed, the formation is not continued, and the generation of a large number of defective products is prevented.

Further, not only the first film thickness measuring means but also the second film thickness measuring means can be used.
Since the film thickness measuring means also measures the thickness of the film on the substrate on the transport path for forming the film, there is no need to measure the film thickness in a separate step from the film formation, The time required for forming the film is short and the burden on the operator is small.

In the semiconductor manufacturing apparatus according to the second aspect, the first
And the second film thickness measuring means measures the film thickness at a plurality of locations in the plane of the substrate, so that a film having a thickness close to a desired value at a plurality of locations in the plane of the substrate is formed on the substrate with high accuracy. Is done.

In the semiconductor manufacturing method according to the third aspect, the film is sequentially formed on the substrate in a plurality of times in the thickness direction.
The thickness of the film to be formed after this measurement is adjusted based on the thickness of the film measured before the last formation of the film.
For this reason, even if the thickness of the formed film is different from the desired value halfway, a film having a thickness close to the desired value is finally formed on the substrate with high accuracy.

In addition, if the thickness of the film measured before the last formation of the film or the thickness of the film measured after the last formation of the film is out of the desired range, the formation of the film is stopped. Therefore, even if a film having a thickness outside the desired range is formed, the formation is not continued, and the generation of a large number of defective products is prevented.

Further, since the thickness of the film is measured at a time before the last formation of the film and at a time subsequent to the last formation of the film, the thickness of the film is measured in a separate step from the formation of the film. The time required for forming the film is short and the burden on the operator is small.

In the semiconductor manufacturing method according to the fourth aspect, since the thickness of the film is measured at a plurality of locations in the plane of the substrate, a film whose thickness at a plurality of locations in the plane of the substrate is close to a desired value is formed on the substrate. Formed with high precision.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, SiO _{2 will be described} on a semiconductor wafer.
An embodiment of the present invention applied to a normal pressure CVD apparatus and a normal pressure CVD method for forming a film will be described with reference to FIGS. FIG. 1 shows the normal pressure C in the present embodiment.
1 schematically shows a VD device. This atmospheric pressure CVD apparatus 1
1 is provided with a muffle 12 and a belt driving unit 1 is provided.
A belt conveyor 14 driven by 3 advances through the muffle 12. The belt conveyor 14 is formed by knitting a round core made of Inconel and having a diameter of 0.5 mm in a cloth shape.

Above the belt conveyor 14, four chambers 16a to 16d are arranged in the traveling direction 15, and the membranes are provided between the chambers 16c and 16d and between the chamber 16d and the outlet of the muffle 12 respectively. Thickness measuring devices 17a and 17b are arranged. The belt conveyor 14 coming out of the muffle 12 is a hydrofluoric acid muffle 21, a pure water tank 2
2. Heater 23 for heating and blowing nitrogen gas
After passing through the inside sequentially, it enters the muffle 12 again.

The atmospheric pressure CVD apparatus 11 has a TEOS (TetraEt
hyl OrthoSilicate), TEB (TriEthylBoron) and TMO
A liquid tank 24 for storing P (TriMethoxyOxidePhosphine) or the like is provided, and each liquid in the liquid tank 24 is pressure-fed to a bubbler 26 via pipes 25a to 25c. When a certain amount of each of the liquids fed from the liquid tank 24 is collected by the bubbler 26, a nitrogen gas is fed into each of the liquids, and each liquid is vaporized by bubbling.

The gas such as TEOS vaporized by the bubbler 26 is sent to the chambers 16a to 16d via the pipe 27, and the vaporized gas such as TEOS is supplied to the chambers 16a to 16d.
A heater (not shown) for preventing liquefaction again before reaching 6d is attached to the pipe 27.

The atmospheric pressure CVD apparatus 11 has an ozone generator 31
The ozone generator 31 generates ozone gas by mixing the supplied oxygen gas and nitrogen gas, and applying a high voltage to the mixed gas to ionize the oxygen gas. This ozone gas is sent to the chambers 16a to 16d via the pipe 32. Chambers 16a-1
An exhaust pipe 33 is also connected to 6d.

FIG. 2 shows a muffle 1 of the atmospheric pressure CVD apparatus 11.
2 and its vicinity. A cassette stage 34 is provided on the entrance side of the muffle 12, and a transfer robot 35 transfers a semiconductor wafer in a wafer cassette on the cassette stage 34 via a load unit 36 to the belt conveyor 1.
Conveyed to 4. The semiconductor wafer coming out of the muffle 12 passes through the unload section 37 to the unload shuttle 4.
1 and the return shuttle 42, and are returned to the original wafer cassette by the transfer robot 35.

FIG. 3 shows the muffle 12. FIG.
As shown in (a), an injector 43 connected to the pipes 27 and 32 is mounted in each of the chambers 16a to 16d, and a gas such as TEOS sent from the bubbler 26 and an injector 43 sent from the ozone generator 31. A source gas 44 composed of an incoming ozone gas and a chemical reaction immediately below the injector 43.

Between the chambers 16a to 16c, between the chambers 16c and 16d and the film thickness measuring devices 17a and 17b,
And nitrogen gas 45 near the inlet and outlet of the muffle 12
Is circulated, the leakage of the raw material gas 44 outside the muffle 12 is prevented by the nitrogen gas 45, and the unreacted raw material gas 44 is diluted with the nitrogen gas 45 and discharged to the factory side via the pipe 33. .

As shown in FIG. 3B, the chambers 16a to 16a
Dozens of heaters 46 are provided in the muffle 12 for heating the 16d and maintaining the source gas 44 at an appropriate reaction temperature. FIG. 4 shows the chamber 16a. The distance d between the semiconductor wafer 47 on the belt conveyor 14 and the injector 43 is adjustable, but this distance is usually more than ten mm.

The Si measured by the film thickness measuring device 17a is
S to be formed by the chamber 16d based on the thickness of the O ₂ film
The thickness of the iO ₂ film, that is, the flow rate of the source gas 44 to be ejected from the injector 43 of the chamber 16d is adjusted, and the SiO ₂ film measured by the film thickness measuring devices 17a and 17b is adjusted.
When the thickness of the O ₂ film is out of the desired range, the chambers 16a to 16a to 1
A control device (not shown) for stopping the formation of the SiO ₂ film by 6d and the conveyance of the semiconductor wafer 47 by the belt conveyor 14 is provided in the atmospheric pressure CVD device 11.

FIG. 5 shows a method of forming an SiO ₂ film on a semiconductor wafer 47 using the normal pressure CVD apparatus 11 as described above. As shown in FIG. 5, first, the transfer robot 35 transfers the semiconductor wafer 47 in the wafer cassette on the cassette stage 34 to the belt conveyor 14.

The semiconductor wafer 47 placed on the belt conveyor 14 enters the muffle 12 and enters the chambers 16a to 16a.
16c, the source gas 44 ejected from the injectors 43 of the chambers 16a to 16c causes a thermochemical reaction on the semiconductor wafer 47, and the semiconductor wafer 4
The SiO ₂ film is sequentially formed on 7. Then, the total thickness of the SiO ₂ film formed in the chambers 16 a to 16 c is set at 9 to 17 locations in the plane of the semiconductor wafer 47.
It is measured by the film thickness measuring device 17a.

If this thickness is within the desired range, the source gas ejected from the injector 43 of the chamber 16d is adjusted so that the total thickness of the SiO ₂ film formed in the entire chambers 16a to 16d becomes a desired value. After adjusting the flow rate of 44 by the controller, an SiO ₂ film is further formed in the chamber 16d.

If the thickness of the SiO ₂ film measured by the film thickness measuring device 17a is out of the desired range, that is, even if the flow rate of the raw material gas 44 injected from the injector 43 of the chamber 16d is adjusted, the chambers 16a to 16d If it is determined that the total thickness of the SiO ₂ film formed as a whole does not reach the desired value, the S 16 by the chambers 16 a to 16 d
The control device stops the formation of the iO ₂ film and the transfer of the semiconductor wafer 47 by the belt conveyor 14.

When the SiO ₂ film is formed in the chamber 16 d, the total thickness of the SiO ₂ film formed in the chambers 16 a to 16 d is measured at 9 to 17 places in the plane of the semiconductor wafer 47 by a film thickness measuring device. Measure at 17b. If this thickness is within the desired range, the SiO
_After the formation of the _two films is completed, the semiconductor wafer 47 is returned to the original wafer cassette via the unload shuttle 41, the return shuttle 42, and the like, and the formation of the SiO ₂ film on another semiconductor wafer 47 is continued. Is done.

If the thickness of the SiO ₂ film measured by the film thickness measuring device 17b is out of the desired range, the control device controls the formation of the SiO ₂ film by the chambers 16a to 16d and the transfer of the semiconductor wafer 47 by the belt conveyor 14. Stop.

The semiconductor wafer 4 is placed in the chambers 16a to 16d.
When an SiO ₂ film is formed on a 7, SiO ₂ film is also formed on the belt conveyor 14. For this reason, muffle 12
Conveyor 14 coming out of the
In the inside, the SiO ₂ film is etched by being exposed to the vapor of hydrofluoric acid, washed in the pure water tank 22, dried by the heater 46,
It enters the muffle 12 again in a clean state.

In the above embodiment, the film thickness measuring device 1 for measuring the thickness of the SiO ₂ film formed halfway is used.
7a is arranged between the chamber 16c and the chamber 16d, but may be arranged between the chamber 16a and the chamber 16b or between the chamber 16b and the chamber 16c. May be.

In the above embodiment, the normal pressure CVD apparatus for forming the SiO ₂ film on the semiconductor wafer and the normal pressure C
This is an application of the present invention to the VD method.
The invention of the present application can also be applied to the case of VD, sputtering, vacuum deposition, forming a polycrystalline Si film on an insulating substrate, and the like.

[0034]

According to the semiconductor manufacturing apparatus of the present invention, a film having a thickness close to a desired value is formed on a substrate with high accuracy and the occurrence of a large number of defective products is prevented beforehand. It can be manufactured with high yield. In addition, since the time required for forming the film is short and the burden on the operator is small, the semiconductor device can be manufactured at low cost.

In the semiconductor manufacturing apparatus according to the second aspect, since a film having a thickness close to a desired value at a plurality of locations in the plane of the base is formed on the base with high accuracy, the semiconductor device is manufactured with a higher yield. be able to.

In the semiconductor manufacturing method according to the third aspect, a film having a thickness close to a desired value is formed on the substrate with high accuracy, and a large number of defective products are prevented from occurring. It can be manufactured with high yield. In addition, since the time required for forming the film is short and the burden on the operator is small, the semiconductor device can be manufactured at low cost.

In the semiconductor manufacturing method according to the fourth aspect, since a film having a thickness close to a desired value at a plurality of locations in the plane of the base is formed on the base with high precision, the semiconductor device is manufactured with a higher yield. be able to.

[Brief description of the drawings]

FIG. 1 is a schematic view of a low pressure CVD apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view of a muffle and its vicinity in a low-pressure CVD apparatus of one embodiment.

3A and 3B show a muffle in a low-pressure CVD apparatus according to one embodiment, wherein FIG. 3A is a side view and FIG. 3B is a cross-sectional view.

FIG. 4 is a side view of a chamber in a low-pressure CVD apparatus according to one embodiment.

FIG. 5 is a flowchart of a process according to one embodiment.

[Explanation of symbols]

11: normal pressure CVD apparatus (semiconductor manufacturing apparatus), 14: belt conveyor (conveying means), 16a to 16d: chamber (film forming means), 17a: film thickness measuring device (first film thickness measuring means), 17b ... A film thickness measuring device (second film thickness measuring means),
47 ... Semiconductor wafer (substrate)

Claims (4)

[Claims] 1. A conveying means for conveying a substrate on a conveying path, a plurality of film forming means for sequentially forming a film in a thickness direction on the substrate conveyed on the conveying path, and a plurality of film forming means First film thickness measurement means for measuring the thickness of the film on the substrate on the transport path before the last formation by means, and following the last formation by the plurality of film formation means A second film thickness measuring means for measuring the thickness of the film on the substrate on the transport path; and a second film thickness measuring means for measuring the thickness based on the thickness measured by the first film thickness measuring means. Later, the film forming means adjusts the thickness of the film to be formed, and when the thickness measured by the first or second film thickness measuring means is outside a desired range, the film forming means Control for stopping the formation and the transfer by the transfer means. The semiconductor manufacturing apparatus characterized by comprising a means. 2. The semiconductor manufacturing apparatus according to claim 1, wherein said first and second film thickness measuring means perform said measurement at a plurality of positions in a plane of said base. 3. a step of sequentially forming a film on the substrate in a plurality of times in a thickness direction in a thickness direction; a step of measuring a thickness of the film on the substrate before the last formation; Adjusting the thickness of the film to be formed after this measurement based on the thickness measured before the last formation, and stopping the formation when the thickness is outside a desired range. Measuring the thickness of the film on the substrate following the last formation; and stopping the formation if the measured thickness following the last formation is outside a desired range. A semiconductor manufacturing method, comprising: 4. The semiconductor manufacturing method according to claim 3, wherein the measurement is performed at a plurality of positions in the plane of the base.