JP2001140077A - Semi-conductor manufacturing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semi-conductor manufacturing device to improve the quality for forming a film on a wafer by uniformly straightening the flow of a reaction gas, forming a uniform reaction condition on a surface of a susceptor, suppressing adhesion and deposition of non-reacted gas or reaction product, and reducing generation of the dust. SOLUTION: In the semi-conductor manufacturing device comprising a vacuum chamber 2, the susceptor 7 for mounting the wafer provided in the vacuum chamber, an upper electrode 9 provided so as to face the susceptor, and a gas feeding means to feed the reaction gas in a space between the susceptor and an upper electrode, the gas feeding means comprises a gas pipe 15 arranged in the horizontal direction through the space between the upper electrode 9 and the susceptor 7, and a plurality of nozzle holes 16 to eject the gas in the horizontal direction are formed in parallel on both side surfaces of the gas pipe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a semiconductor manufacturing apparatus. More specifically, the present invention relates to a batch-type parallel plate type semiconductor manufacturing apparatus for forming a film on a plurality of wafers while supplying a reaction gas in a vacuum chamber.

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, a semiconductor manufacturing apparatus such as a CVD apparatus or a dry etching apparatus is used for forming a thin film or a pattern on a wafer.
In such a semiconductor manufacturing apparatus, it is necessary to reduce impurity particles and dust adhering to the wafer surface as much as possible with the improvement in the degree of integration (density) of the semiconductor circuit.

FIG. 4 is a sectional view of a conventional semiconductor manufacturing apparatus. This example shows a batch-type parallel plate type plasma CVD apparatus 1, which comprises, for example, a vacuum chamber 2 having a substantially cylindrical shape (the cylinder axis is in a vertical direction) and a load lock chamber 3 adjacent to the vacuum chamber. A door 4 is provided between the load lock chamber 3 and the vacuum chamber 2. The vacuum chamber 2 is connected to a vacuum pump (not shown) through a vacuum pipe 5 connected to an exhaust port 6.

A disk-shaped susceptor 7 constituting a lower electrode is provided in the vacuum chamber 2, and a plurality of wafers 8 are mounted on the susceptor 7. An upper electrode 9 is provided facing the upper surface of the susceptor 7. The chamber floor on the back side of the upper electrode 9 and on the lower side of the susceptor 7 is covered with quartz plates 10 and 11 for protection and for preventing plasma from escaping outside the electrode. Further, the periphery of the upper electrode 9 and the susceptor 7 is surrounded by a shield plate 12.

A gas pipe 13 for supplying a reaction gas to the plasma generating space P between the susceptor 7 and the upper electrode 9 is provided adjacent to the side surface of the susceptor 7.
As shown in FIG. 5, the gas pipe 13 includes two gas pipes 13a, a reaction gas pipe 13a for a film forming reaction by a CVD process and an etching gas pipe 13b for performing cleaning after each film forming process or periodically.
a and 13b. Each gas pipe 13a, 1
A horizontal slit (not shown) that opens toward the space P on the upper surface of the susceptor is formed at the tip of 3b.
Ejects reactive gas or cleaning gas.

In the plasma CVD apparatus 1 having such a configuration, the vacuum chamber 2 is maintained at a predetermined vacuum pressure,
A high-frequency voltage is applied between the two electrodes while a predetermined reaction gas is ejected from the reaction gas pipe 13a into the space P between the upper electrode 9 and the susceptor (lower electrode) 7 as shown by an arrow A.
As a result, plasma is excited in the space P between the two electrodes, the reaction gas is ionized, and a predetermined thin film is formed on the surface of the wafer 8 on the susceptor 7 by vapor phase growth.

At the time of cleaning or etching,
Similarly, in a predetermined vacuum state, the etching gas pipe 13b
A cleaning gas (etching gas) is supplied from the substrate to etch the inside of the chamber or the wafer surface.

[0008]

However, in the conventional semiconductor manufacturing apparatus, the gas pipe 13a (13
b) is erected on the side surface of the susceptor 7, and the reaction gas is ejected from the outside of the side surface toward the space P on the susceptor upper surface, so that the gas flow toward the center of the upper surface of the susceptor 7 as shown in FIG. With A, flows (arrows B, C, D, E, and F) in which the flow velocity and direction are not constant are generated unevenly toward the rear side of the pipe and the side or lower side of the susceptor.
As a result, the ionization by the plasma becomes incomplete or non-uniform, and the reaction state becomes uneven, and unreacted or incompletely reacted products are generated.
The deposition reactant 14 is adhered to the shield plate 12 and other wall surfaces in the vacuum chamber 2 and the like, as shown by oblique lines in FIG. Such a deposition reactant 14 causes dust and re-adheres to the wafer surface, lowering the film formation quality and lowering the yield. In addition, fine particles such as unreacted gas due to non-uniform ionization adhere to the wafer surface to form a cloudy film, impeding normal reaction and deteriorating quality.

The present invention has been made in consideration of the above-mentioned prior art, and uniformly rectifies the flow of a reaction gas to form a uniform reaction state on the upper surface of the susceptor, thereby adhering unreacted gas and reaction products in an uneven state. It is an object of the present invention to provide a semiconductor manufacturing apparatus which suppresses deposition and reduces generation of dust to improve film formation quality on a wafer.

[0010]

In order to achieve the above object, the present invention provides a vacuum chamber, a susceptor for mounting a wafer provided in the vacuum chamber, an upper electrode provided opposite to the susceptor, In a semiconductor manufacturing apparatus comprising: a gas supply unit that supplies a reaction gas to a space between a susceptor and an upper electrode, the gas supply unit includes:
A semiconductor pipe comprising a gas pipe disposed in a horizontal direction through a space between the upper electrode and a susceptor, and a plurality of nozzle holes for jetting gas in a horizontal direction are formed in parallel on both side surfaces of the gas pipe. Provide equipment.

According to this structure, the rectified reaction gas is uniformly supplied from the gas pipe disposed in the space on the upper surface of the susceptor to the entire upper surface of the susceptor through the plurality of nozzle holes on both sides in the horizontal direction, and is supplied onto the wafer. In addition to improving the uniformity of film deposition, the quality of the film is improved by eliminating the fogging of the wafer surface, and the generation of impurity particles and dust is suppressed by reducing the reaction deposits adhering to the inside of the vacuum chamber, and the yield is reduced. Is improved.

In a preferred embodiment, the gas pipe is
The susceptor is formed of a straight pipe passing through the center of the upper surface.

According to this structure, by providing a straight gas pipe passing through the center of the upper surface of the susceptor in the space between the susceptor and the upper electrode, gas can be uniformly supplied to the upper surface of the susceptor with a simple structure. .

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a semiconductor manufacturing apparatus according to an embodiment of the present invention.

This embodiment shows a batch type parallel plate type plasma CVD apparatus 1 as in the example of FIG.
The configuration of the gas pipe 15 is different from the example of FIG. The basic configuration of the plasma CVD apparatus 1 is shown in FIG.
The reaction chamber is constituted by, for example, a substantially cylindrical (vertical axis of the cylinder axis) vacuum chamber 2 constituting a reaction chamber and a load lock chamber 3 adjacent thereto. A door 4 is provided between the load lock chamber 3 and the vacuum chamber 2. The vacuum chamber 2 is connected to a vacuum pump (not shown) through a vacuum pipe 5 connected to an exhaust port 6.

A disk-shaped susceptor 7 constituting a lower electrode is provided in the vacuum chamber 2, and a plurality of wafers 8 are mounted on the susceptor 7. An upper electrode 9 is provided facing the upper surface of the susceptor 7. The chamber floor on the back side of the upper electrode 9 and on the lower side of the susceptor 7 is covered with quartz plates 10 and 11 for protection and for preventing plasma from escaping outside the electrode. Further, the periphery of the upper electrode 9 and the susceptor 7 is surrounded by a shield plate 12.

In this embodiment, a gas pipe 1 for supplying a reactive gas is provided in a space between the susceptor 7 and the upper electrode 9.
5 are provided. This gas pipe 15 is connected to the susceptor 7.
And a straight pipe portion 15b on the upper surface of the susceptor 7. The tip of the straight pipe portion 15b is fixed and held by a support rod (or pipe) 17, and is supported at a position at a certain height on the upper surface of the susceptor 7.

The straight pipe portion 15b of the gas pipe 15 has a structure shown in FIG.
As shown in FIG. 2, a plurality of nozzle holes 16 are formed in parallel on both side surfaces in the horizontal direction (left and right side surfaces in FIG. 2C).
Each nozzle hole 16 is formed, for example, with a hole diameter of about 1 mm and a pitch of about 10 mm. Note that these nozzle holes 1
The diameter and pitch of 6 are appropriately set according to the size of the vacuum chamber, the type of gas used, the flow rate, and other process conditions. In this case, prepare a plurality of types of gas pipes in advance,
It may be appropriately selected or replaceable according to the process conditions. Further, the hole diameter and the pitch may be changed so that a gas with a uniform flow rate is ejected from each nozzle hole 16, for example, the diameter may be larger for the nozzle hole on the tip side.

The rising portion 15a and the straight pipe portion 15b of the gas pipe 15 are connected via a bent portion 19 having an appropriate degree of curvature. The bent portion 19 has, for example, R = about 10 mm. By continuing with such a radius of curvature,
The gas flow is smooth, and the unreacted gas and reaction products are prevented from being deposited on the inner surface of the pipe.

Further, a gas escape hole 18 is formed at a lower portion of the tip of the straight pipe portion 15b. By providing the gas escape hole 18, the reactive gas does not stay at the tip of the pipe and stagnates, so that the gas flow is smooth and the unreacted gas and reaction products are prevented from being deposited on the inner surface of the pipe. .

The straight pipe portion 15b of the gas pipe 15 is shown in FIG.
As shown in (A), the susceptor 7 is disposed on the upper surface of the susceptor 7 on its diameter through the center. Such a gas pipe 1
As shown by the arrow S in FIG. 4B, the reaction gas is rectified and uniformly injected onto the upper surface of the susceptor 7 from the nozzle holes 16 on both sides of the straight pipe portion 15b of FIG.

When performing cleaning or etching processing in the vacuum chamber 2, a gas pipe (not shown) to be used is switched, and an etching gas is supplied using the same gas pipe 15. Thus, the gas pipe 1
By using the common 5, the reaction deposits inside the gas pipe 15 and the nozzle hole 16 are efficiently removed, the unreacted gas and reaction products are prevented from adhering to the gas pipe, and the generation of particles and dust is suppressed. .

[0023]

As described above, according to the present invention, the reaction gas rectified from the gas pipe disposed in the space on the upper surface of the susceptor through the plurality of nozzle holes on both sides in the horizontal direction is uniformly spread over the entire upper surface of the susceptor. The supply and uniformity of the film formation on the wafer are improved, and the quality of the film is improved without clouding of the wafer surface. Further, the amount of reaction deposits adhering to the inside of the vacuum chamber is reduced, so that generation of impurity particles and dust is suppressed, and the yield is improved.

[Brief description of the drawings]

FIG. 1 is a sectional configuration view of a plasma CVD apparatus according to the present invention.

FIG. 2 is a detailed explanatory view of a gas pipe of the apparatus of FIG.

FIG. 3 is an explanatory view of the arrangement of the gas pipe of FIG. 2;

FIG. 4 is a cross-sectional configuration diagram of a conventional plasma CVD apparatus.

FIG. 5 is an explanatory view of the arrangement of gas pipes in the apparatus of FIG.

FIG. 6 is an explanatory diagram of a state of adhesion of a deposition reactant of the apparatus of FIG.

[Explanation of symbols]

1: plasma CVD apparatus, 2: vacuum chamber, 3: load lock chamber, 4: door, 5: vacuum pipe, 6: exhaust port,
7: susceptor, 8: wafer, 9: upper electrode, 10,
11: quartz plate, 12: shield plate, 13: gas pipe,
14: deposition reactant, 15: gas pipe, 15a: rising part, 15b: straight pipe part, 16: nozzle hole, 17: support rod (or pipe), 18: relief hole, 19: bent part

Claims (2)

[Claims] A vacuum chamber; a wafer mounting susceptor provided in the vacuum chamber; an upper electrode provided opposite the susceptor; and a gas supply for supplying a reaction gas to a space between the susceptor and the upper electrode. Wherein the gas supply means comprises a gas pipe disposed in a horizontal direction through a space between the upper electrode and a susceptor, and a plurality of gas pipes for horizontally ejecting gas to both side surfaces of the gas pipe. A semiconductor manufacturing apparatus wherein nozzle holes are formed in parallel. 2. The semiconductor manufacturing apparatus according to claim 1, wherein said gas pipe comprises a straight pipe passing through a central portion of an upper surface of said susceptor.