JPH04162427A - Device and method for vapor phase film formation - Google Patents

Abstract

PURPOSE:To equalize the thickness distribution and characteristic distribution of a film by alternately supplying the gas introducing ports of a pair of electrode plates with a raw gas, alternately applying voltage to a pair of the electrode plates, generating plasma and forming the film to a body to be film- formed. CONSTITUTION:A gas introducing port 1a is supplied with a raw gas, and an electrode plate 1 is fed with power after five or ten sec. The supply of the raw gas of the gas introducing port 1a and the supply of power of the electrode plate 1 are interrupted when one min elapses. A gas introducing port 2a is supplied instantaneously with the raw gas, and an electrode plate 2 is fed with power after five or ten sec. The supply of the raw gas of the gas introducing port 2a and the supply of power of the electrode plate 2 are interrupted when one min elapses. The gas introducing port 1a is fed instantaneously with the raw material gas, and afterwards a series of the same operation is repeated. The rate of film formation is brought to approximately fifty Angstrom /min, and a silicon nitride film (Si3N4) in thickness of 1000Angstrom can be formed on an Si chip 7 for approximately twenty min.

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] The present invention relates to a vapor-phase film-forming apparatus and a vapor-phase film-forming method, and particularly to a positive column plasma CVD apparatus and a vapor-phase film-forming method using the apparatus.

The purpose is to make the thickness distribution and property distribution of the coating formed on the object to be coated uniform.

They were placed across the object to be film-formed. A pair of electrode plates each having a gas inlet are integrated into each electrode plate.

A gas supply plate having a plurality of gas supply holes.

a gas supply plate that supplies the raw material gas introduced from the gas inlet to the object to be film-formed through the plurality of gas supply holes; a high-frequency power source that applies a voltage to each electrode plate; and a high-frequency power supply that applies voltage to each electrode plate; a mechanism for alternately and intermittently supplying source gas from the gas inlet; and a mechanism for alternately and intermittently applying a voltage supplied from the high-frequency power source to the pair of electrode plates;
A vapor phase deposition method in which a source gas is alternately supplied to the gas inlets of the pair of electrode plates, and a voltage is alternately applied to the pair of electrode plates to generate plasma and form a film on the object to be coated. Consists of a membrane device.

Furthermore, when forming a film on an object to be film-formed using the above-mentioned vapor phase film forming apparatus, the time for supplying the raw material gas to the gas inlet of each electrode plate includes at least the time for applying voltage to each electrode plate. Constructed using a phase film formation method.

[Industrial application field]

The present invention relates to a vapor-phase film-forming apparatus and a vapor-phase film-forming method, and more particularly to a positive column plasma CVD apparatus and a vapor-phase film-forming method using the apparatus.

2. Description of the Related Art Recently, with the miniaturization of semiconductor devices, the thickness of films formed inside semiconductor devices has become thinner, and it is required to make the film thickness distribution within a substrate uniform during the manufacturing process.

In addition, as plastic packages become lighter, thinner, shorter and smaller, it is necessary to avoid package cracks due to thermal stress during mounting, and to increase density due to the emergence of TAB (tape automated bonding), hybrid ICs, bare chips, etc. In order to maintain high reliability, the thickness of the nitride film formed on the metal part before molding is required to have a uniform thickness distribution.

[Conventional technology]

FIG. 4 is used for film formation. It is a perspective view of the main part of a conventional solar plasma CVD apparatus, and 7 is a substrate on which a film is to be formed.

12 and 13 are electrode plates, 14 is a high frequency power source, and 15 is a container.

16 represents the mesh top plate.

The substrate 7 to be film-formed is placed in a space in the container 15 in a floating state or in a grounded state, and electrode plates 1 are placed on both sides of the substrate 7.
2.13 is placed. Raw material gas is supplied into the container 15 from the upper part of the container 15 through the mesh top plate I6, and a high frequency voltage is applied to the electrode plates 12.13 to turn the raw material gas into plasma, thereby growing a film on the substrate 7 to be film-formed. For example, when growing a silicon nitride film, for example, silane and nitrogen are used as source gases.

However, as shown in FIG. 4, when the deposition target substrate 7 is three-dimensionally arranged inside the container 15, the decomposition of the raw material gas is significant at the upper part of the container 15, which is the supply side of the raw material gas. The thickness of the silicon nitride film grown on the upper part of 7 is large, and due to the influence of silane which decomposes quickly, a silicon nitride film rich in Si components and having a high refractive index grows and grows on the lower part of the deposition substrate 7 on the exhaust side. Silicon nitride film has a small thickness.

A silicon nitride film with a small Si component and a low refractive index is grown. Therefore, both the film thickness and film quality become non-uniform.

There is also the problem that discharge tends to concentrate in the center due to interference of discharge from the left and right electrode plates 12, 13.

[Problem to be solved by the invention]

In view of the above-mentioned problems, the present invention provides a vapor-phase film-forming apparatus and a vapor-phase film-forming method having a structure designed to make the thickness and film quality distribution of the film grown on the film-forming substrate 7 uniform. The purpose is to

[Means to solve the problem]

FIG. 1 is a perspective view of the main parts of the vapor phase film forming apparatus of the present invention.

The above-mentioned subjects were arranged with the film-formed object 7 in between.

A pair of electrode plates 1.2 having gas inlets 1a, 2a.

Each electrode plate 1. 2, and has a plurality of gas supply holes, the gas inlet 1a.

A voltage is applied to the gas supply plate 3.4 which supplies the raw material gas introduced from 2a to the object 7 through the plurality of gas supply holes, and to each electrode plate 1.2.

High frequency power sources 5, 6 and the gas inlet 1 of the pair of electrode plates
a, a mechanism that alternately and intermittently supplies source gas from 2a, and a mechanism that alternately and intermittently applies voltage supplied from the high frequency power sources 5 and 6 to the pair of electrode plates 1 and 2. The pair of electrode plates 1. 2 gas inlet ports 1a, 2a
While supplying raw material gas alternately to the pair of electrode plates 1. 2
This problem can be solved by a vapor phase film forming apparatus which generates a plasma by alternately applying a voltage to the film forming body 7 to form a film on the film forming object 7.

Further, when forming a film on the object 7 to be film-formed using the above-mentioned vapor phase film-forming apparatus, the gas inlet ports 1a and 2 of each electrode plate 1 and 2 are used.
The time for supplying raw material gas to a is at least equal to each electrode plate 1.
．． This problem is solved by a vapor phase film forming method that includes a time period in which a voltage is applied.

[Effect]

In the present invention, an integrated gas supply plate 3.4 is attached to the pair of electrode plates 1 and 2, and the pair of electrode plates l.

The raw material gas is alternately supplied to the gas inlet ports 1a and 2a of 2, and a voltage is alternately applied to the pair of electrode plates 1 and 2 to generate plasma and form a film on the object 7 to be coated. , the thickness of the film formed on the film-formed object near one electrode plate and the film-formed object near the other electrode plate are equal.

The decomposition of the raw material gas is faster in the areas near both electrode plates, so the film thickness tends to be thicker than in the center (though there is a tendency for it to be thicker in both the film thickness distribution and film quality distribution compared to conventional vapor phase film deposition equipment). Much more similar coatings can be formed.

Furthermore, since voltages are applied alternately to the pair of electrode plates 1 and 2, voltages are not applied to the pair of electrode plates 1 and 2 at the same time. Therefore, no discharge concentration occurs in the center.

Furthermore, when supplying the raw material gas and applying voltage intermittently, by starting the supply of the raw material gas earlier than the application of the voltage, the raw material gas can be spread over the object to be film-formed, and then the voltage can be applied. If discharge is performed, it is effective to make the film thickness distribution and film quality distribution uniform.

〔Example〕

FIG. 1 is a perspective view of the main parts of the vapor phase film forming apparatus of the present invention.

FIG. 2 is a side sectional view of the electrode plate and the gas supply plate.

1.2 is the electrode plate, 1a, 2a is the gas inlet, 3, 4
is a gas supply plate, 3a to 3j are gas supply holes, 5 and 6 are high frequency power supplies, 7 is a film-forming object, 8 is a first support, and 9 is a second support.
, 10 is a third support, and 11 is an insulator.

Electrode plate 1. 2 is made of metal and has, for example, a 1 m opening, with gas inlet ports 1a and 2a formed in the center. Gas inlet 1
A, Although not shown, a mechanism for intermittently supplying raw material gas is attached to the tip of 9 and 2a.

The gas supply plate 3.4 is made of metal and has a 1 m opening, for example.

It is integrated with the electrode plate 1.2 via the insulator 11.

Gas supply holes 3a to 3j are opened on the entire surface of the gas supply plates 3 and 4. What is the pitch of the gas supply holes 3a to 3j?

For example, the diameter is 30 mm, and the diameter is 10 mm.

The high frequency power sources 5 and 6 are power sources with a frequency of 13.56 MHz, for example, and each power source is equipped with a mechanism for intermittently applying a voltage to the electrode plate 1.2.

The film-forming object 7 is one on which a film is to be formed.

In this example, in order to investigate the distribution of film thickness and film quality, assuming that the chip is housed in a package and molded, 81 chips with a 10 mm opening were selected as the film-forming object 7, and the chips were arranged as follows. I made it.

First, three Si chips were attached to a lead frame 8, which was a first support. Next, ten lead frames 8 were fixed to both sides of an aluminum plate 9, which was a second support. Ten of the aluminum plates 9 were stood side by side on an aluminum stand 10, which was a third support. Therefore, a total of 6 Si chips are needed to investigate the distribution of film thickness and film quality.
There are 00 items. The film-forming object 7 may be in either a floating state or a grounded state.

Electrode plate l, 2. Gas supply plates 3, 4. Film-forming object 7゜1st~
The third supports 8 to IO are arranged in a vacuum chamber (not shown).

1003 CCM of silane (SiH<) as a raw material gas,
16003 CCM of nitrogen (N2), gas inlet 1a,
Supplied from 2a.

13.56M)jz at reduced pressure of 0.01Torr,
A power of 1 kW was supplied to the electrode plates 1 and 2 to generate plasma, and the raw material gas was decomposed and reacted to cause a silicon nitride film (Si3N4) to be deposited on the Si chip 7.

FIG. 3 is a diagram showing the timing of raw material gas supply and power supply.

First, raw material gas is supplied to the gas inlet 1a, and after 5 to 10 seconds, power is supplied to the electrode plate 1. After one minute has elapsed, the supply of raw material gas to the gas inlet 1a and the supply of electric power to the electrode plate (2) are cut off. Raw material gas is immediately supplied to the gas inlet 2a, and power is supplied to the electrode plate 2 after 5 to 10 seconds. After one minute has passed, the supply of raw material gas to the gas inlet 2a and the supply of electric power to the electrode plate 2 are cut off. The raw material gas is immediately supplied to the gas' inlet 1a, and the same series of operations is repeated thereafter. In this case, the film forming rate is about 50 A/min.

A silicon nitride film (Si3N4) with a thickness of 1,000 layers could be formed on the Si chip 7 in about 20 minutes.

The film thickness distribution of the 600 Si chips 7 was +11% and -13%, mainly for 1000 people. The distribution of refractive index as an evaluation of film quality was 2.02 to 2.16.

For comparison, S1 was measured using a conventional solar plasma CVD apparatus.
600 chips 7 are arranged in the same manner as above to have a thickness of 100.
When forming the OA silicon nitride film (Si3N4),
The film thickness distribution is +60% mainly for 1000 people.

=55%. The refractive index distribution as an evaluation of film quality was 2.05 to 3.08.

Therefore, according to the vapor phase film forming apparatus of the present invention, it is possible to form a film with a much more uniform film thickness distribution and film quality distribution than conventional methods.

The timing of raw material gas supply and power supply is determined by providing a timing adjustment mechanism so that the time for supplying power to electrode plate 1 is always included in the time for supplying raw material gas to gas inlet 1a, and similarly, for supplying raw material gas to electrode plate 2. The time for supplying electric power is always included in the time for supplying raw material gas to the gas inlet 2a.

Although this embodiment has been shown assuming a case where a chip is housed in a package and molded, the vapor phase film forming apparatus and vapor phase film forming method of the present invention can be used to form interlayer insulating films and other films of semiconductor devices. Of course, it can also be applied to

〔Effect of the invention〕

As explained above, according to the present invention, the problem occurs in the steps from semiconductor device manufacturing to package mounting. In film formation by vapor phase growth, distribution of film thickness and film quality can be made uniform.

The present invention is particularly suitable for mass production, maintains processes with good reproducibility, and contributes to high reliability of semiconductor devices.

[Brief explanation of drawings]

FIG. 1 is a perspective view of the main parts of the vapor phase film forming apparatus of the present invention. FIG. 2 is a side sectional view of the electrode plate and gas supply plate. FIG. 3 is a diagram showing the timing of raw material gas supply and power supply. FIG. 4 is a perspective view of the main parts of a conventional solar plasma CVD apparatus. In fig. 1.2 is the electrode plate. 1a and 2a are gas inlets. 3.4 is the gas supply plate. 3a to 3j are gas supply holes. 5.6 is a high frequency power supply. 7 is a substrate on which a film is to be formed, which is an object on which a film is to be formed, and is a Si chip. 8 is a first support body, which is a lead frame. 9 is a second support body, which is an aluminum plate. 10 is a third support body, which is an aluminum stand. 11 is an insulator. 12 and 13 are electrode plates. 14 is a high frequency power supply. 15 is a container. 16 is the 7° sunlight coming from the top of the mesh top plate.

Claims (1)

[Scope of Claims] [1] A pair of electrode plates (1, 2) having gas inlets (1a, 2a) disposed with a film-forming object (7) in between;
A gas supply plate integrated with each electrode plate (1, 2) and having a plurality of gas supply holes, the gas inlet (1a, 2a)
), applying a voltage to the gas supply plates (3, 4) that supply the raw material gas introduced from the plurality of gas supply holes to the object (7) to be film-formed (7), and each electrode plate (1, 2). a high frequency power source (5, 6), a mechanism that alternately and intermittently supplies raw material gas from the gas inlets (1a, 2a) of the pair of electrode plates, and the pair of electrode plates (1, 2), The high frequency power source (5, 6)
and a mechanism for alternately and intermittently applying a voltage supplied from the pair of electrode plates (1a, 2a), and a mechanism for alternately supplying raw material gas to the gas inlet ports (1a, 2a) of the pair of electrode plates (1a, 2a); , 2) to generate plasma by alternately applying a voltage to the film-forming object (7).
) A vapor phase film forming apparatus characterized by forming a film on. [2] A film-forming object (7
), the time for supplying the raw material gas to the gas inlets (1a, 2a) of each electrode plate (1, 2) is at least the time for applying voltage to each electrode plate (1, 2). A vapor phase film forming method characterized by comprising: