JP2000331939A - Film-forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve evenness in the film-thickness distribution of a thin film formed on a wafer surface, related to a semiconductor manufacturing device. SOLUTION: An epitaxial growth device 1 comprises a process chamber 2, and a liner part 2A which forms a part of the side part of the process chamber 2 is provided with gas support openings 3a to 3e and gas exhaust opening 4 which each other. A susceptor 7 for supporting wafer W is provided in the process chamber 2, and a pre-heating ring 9 is provided between the liner part 2A and the susceptor 7. At the upper part of the pre-heating ring 9, guide plates 11a-11f extending on a placement part 7a side of the susceptor 7 from the tip of a plurality of side walls 10 which form the gas supply openings 3a to 3e are provided side by side in horizontal direction. The guide plates 11a to 11f rectify each reactive gas guided into the process chamber 2 and guide it to a specified region on the surface of wafer W placed on the placement part 7A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming apparatus, such as an epitaxial growth apparatus, for forming a film by flowing a reaction gas along the surface of an object to be processed and causing a thermal decomposition reaction.

[0002]

2. Description of the Related Art A conventional single-wafer type epitaxial growth apparatus is made of, for example, quartz glass and has a processing chamber having a gas supply port and a gas exhaust port, and is provided in the processing chamber to support a semiconductor wafer. The apparatus includes a susceptor and a plurality of halogen lamps radially arranged above and below the processing chamber. In such an epitaxial growth apparatus, after the wafer is placed on the susceptor, the halogen lamp is turned on to heat the wafer, and when the reaction gas is introduced into the processing chamber from the gas supply port, the wafer heated to a predetermined temperature is heated. The reaction gas flows in a laminar flow state along the surface of the wafer, and a thermal decomposition reaction of the reaction gas occurs to form a thin film on the wafer surface.

In such a film forming process, the film thickness distribution of the thin film formed on the wafer surface tends to be non-uniform due to factors such as the location of the halogen lamp and the flow rate of the reaction gas. . So, conventionally,
A plurality of gas supply ports are provided in the processing chamber, and the flow rate ratio of the reaction gas introduced into the processing chamber from each gas supply port is adjusted to improve the film thickness distribution of the thin film formed on the wafer surface. .

[0004]

However, as described above, by dividing the flow of the reaction gas into a plurality of zones and controlling the flow ratio of the reaction gas in each zone, the uniformity of the film thickness of the thin film on the wafer can be reduced. There were limits to improvement.

An object of the present invention is to provide a film forming apparatus capable of improving the uniformity of the film thickness distribution of a thin film formed on a wafer surface.

[0006]

In order to achieve the above object, the present invention provides a method of forming a film by introducing a reaction gas into a processing chamber, flowing the gas along the surface of the object to be processed, and causing a thermal decomposition reaction. Provided is a film forming apparatus for performing, which includes a guide unit for guiding a reaction gas introduced into a processing chamber to a surface of an object to be processed.

By providing the guide member in this manner, the flow direction of the reaction gas can be controlled, so that the reaction gas flows toward a region where the thickness of the thin film tends to be insufficient on the wafer surface. In this case, the uniformity of the thickness of the thin film formed on the wafer surface can be improved.

According to another aspect of the present invention, there is provided a processing chamber having a gas supply port, and a wafer support member provided in the processing chamber and having a mounting portion on which an object to be processed is placed. A film formation apparatus for introducing a reaction gas into a processing chamber through a gas supply port, flowing the gas along a surface of a processing object, and performing a thermal decomposition reaction to form a film. Provided is a film forming apparatus provided with a guide member extending toward a surface of an object to be processed and extending a reaction gas introduced into a processing chamber.

By providing the guide member in this manner, the flow direction of the reaction gas can be controlled at a position close to a region where the thermal decomposition reaction is performed (hereinafter, referred to as a reaction region). By precisely adjusting the flow, the uniformity of the film thickness distribution of the thin film formed on the wafer surface can be improved. Specifically, since the reaction gas is diffused from a position near the reaction region, when the processing chamber has a plurality of gas supply ports, the reaction gases introduced from each gas supply port are separated from the reaction region. It will be mixed at a remote location. This makes it easier to control the flow of the reaction gas, and by adjusting the flow of the reaction gas toward the region where the film thickness of the thin film tends to be insufficient on the wafer surface, the uniformity of the film thickness of the thin film on the wafer is improved. Can be improved.

In the above-described semiconductor manufacturing apparatus, for example, a heating member for heating the reaction gas introduced from the gas supply port is provided outside the wafer support member in the processing chamber. A guide member is provided.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows a single-wafer type epitaxial growth apparatus for forming a silicon wafer as an object to be processed one by one as a film formation apparatus according to the present invention, and FIG. FIG. 2 is a plan sectional view of the epitaxial growth apparatus. In the figure, an epitaxial growth apparatus 1
Has a processing chamber 2 made of quartz glass, and a liner portion 2A forming a part of a side portion of the processing chamber 2 has a plurality of (here, five) gas supply ports 3a.
3e and the gas exhaust port 4 are provided to face each other.

A gas supply pipe 5a is connected to a gas supply port 3c located at the center among the gas supply ports 3a to 3e.
A gas supply pipe 5b is connected to the gas supply ports 3b and 3d located outside the gas supply port 3c in the horizontal direction, and further connected to the gas supply ports 3a and 3e located outside the gas supply ports 3b and 3d in the horizontal direction. Is connected to a gas supply pipe 5c, and the flow of the reaction gas introduced into the processing chamber 2 is 3
It is divided into zones. A gas exhaust duct 6 is connected to the gas exhaust port 4.

In the processing chamber 2, a susceptor 7, which is a wafer support member for supporting the wafer W, is provided. The susceptor 7 has a disk shape made of a graphite material coated with silicon carbide, and has a concave mounting portion 7a on which a wafer W is mounted on an upper surface portion. The susceptor 7 is horizontally supported at three points from the back side by a quartz glass support shaft 8 erected below the processing chamber 2, and the support shaft 8 is rotationally driven by a drive motor (not shown). This allows the susceptor 7 to rotate.

A preheating ring 9 for heating the reaction gas supplied to each of the gas supply ports 3a to 3e is provided between the liner section 2A and the susceptor 7, and a preheating ring 9 is provided on the mounting section 7a. An effective thermal decomposition reaction can be performed on the supported wafer W.

On the upper part of such a preheating ring 9,
Six guide plates 11a to 11f extending from the tips of the plurality of side walls 10 forming the gas supply ports 3a to 3e to the mounting portion 7a side of the susceptor 7 are arranged side by side in the horizontal direction. These guide plates 11a to 11f rectify the reaction gas introduced into the processing chamber 2 from the respective gas supply ports 3a to 3e, and guide the reaction gas to a predetermined region on the surface of the wafer W placed on the mounting portion 7a. . Of the guide plates 11a to 11f, the outermost guide plates 11a and 11f have a substantially rectangular parallelepiped shape, and are arranged substantially straight with respect to the corresponding side wall 10. Each of the guide plates 11b to 11e has a tapered horizontal section, and the corresponding side wall 10 has a tapered shape.
Is slightly inclined outward with respect to the susceptor 7, and is arranged so as to become thicker with respect to the susceptor 7. This allows
The horizontal interval between adjacent guide plates gradually decreases toward the susceptor 7 side.

A plurality of halogen lamps (infrared lamps or far infrared lamps) 12 for heating the wafer W placed on the mounting portion 7a of the susceptor 7 to a high temperature are provided above and below the processing chamber 2. Are radially arranged.

In the epitaxial growth apparatus 1 configured as described above, after the wafer W is mounted on the mounting portion 7a of the susceptor 7, the power of the halogen lamp 12 is increased to heat the wafer W to the processing temperature, and to heat the wafer W to the processing temperature. Is rotated, a reaction gas such as a trichlorosilane (SiHCl 3) gas or a dichlorosilane (SiH 2 Cl 2) gas is supplied to each of the gas supply ports 3 a to 3 by gas supply pipes 5 a to 5 c.
e to the processing chamber 2. Then, the reaction gas heated by the preheating ring 9 flows in a laminar state along the surface of the wafer W heated to a predetermined temperature, and a single crystal of silicon is epitaxially grown on the wafer W to form a thin film. .

FIG. 3 shows an example of a conventional epitaxial growth apparatus as a comparative example. In FIG. 1, the conventional epitaxial growth apparatus 100 includes the above-described guide plate 1.
1a to 11fc are not provided. Other configurations of the epitaxial growth apparatus 100 are the same as those of the above-described epitaxial growth apparatus 1.

In such a conventional epitaxial growth apparatus 100, in order to improve the film thickness distribution of the thin film, which tends to become non-uniform due to factors such as the installation position of the halogen lamp 12 and the flow rate of the reaction gas, each of the gas supply ports 3a to 3a. 3e, by adjusting the flow ratio of the reaction gas introduced into the processing chamber 2;
The wafer is being formed. For example, as shown in FIG. 4A, the film thickness distribution of the thin film formed on the wafer surface is excessive in the inner region A and the outer region B of the wafer, and the thickness distribution between the inner region A and the outer region B is large. If there is a tendency for the thin film to be insufficient in the intermediate region C, the gas supply ports 3b and 3d
The flow rate of the reaction gas supplied to the gas supply ports 3a, 3c,
By increasing the flow rate of the reaction gas supplied to 3e, the formation of the thin film in the inner region A and the outer region B is suppressed, and the formation of the thin film in the intermediate region C is promoted. FIG. 4A shows a film thickness distribution of the thin film M formed on the wafer surface when the wafer is cut in the diameter direction.

However, in this case, the gas supply pipe 5a
Since the respective reaction gases blown out to the gas supply ports 3a to 3e from the gas supply ports 3a to 3e diffuse from the portions of the gas supply ports 3a to 3e, the reaction gases from the adjacent gas outlets as shown by dotted lines in FIG. However, they are mixed with each other in a region where the thermal decomposition reaction is actually performed (hereinafter, referred to as a reaction region). Therefore, the formation of the thin film is most promoted in the mixed region of the reaction gas on the wafer W, and it is difficult to improve the film thickness distribution of the thin film M as shown in FIG.

On the other hand, in the present embodiment, since the guide plates 11a to 11e extending from the end of the side wall 10 to the susceptor 7 side are provided above the preheating ring 9, the gas supply pipes 5a to 5c are connected to the gas supply ports 3a. Each of the reaction gases blown out to the guide plates 11a to 3e as shown by the dotted line in FIG.
11e, that is, from the position on the downstream side in the flow direction of the reaction gas from the comparative example. Accordingly, the reactant gases are mixed with each other at a position distant from the reaction region, as shown by a dotted line in FIG. For this reason, when the thin film M has a film thickness distribution as shown in FIG. 4A, the flow rate of the reaction gas supplied to the gas supply ports 3b and 3d is changed as described above. By setting the flow rate of the reaction gas to be larger than that supplied to 3e, formation of a thin film in the inner region A and the outer region B of the wafer W is reliably suppressed. As a result, the film thickness distribution of the thin film M becomes substantially uniform as shown in FIG. As a specific example, the thickness error of the thin film could be suppressed to 1% or less.

Although the preferred embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above embodiment. For example, in the above embodiment, the guide plate 1
Although 1a to 11e are configured to extend to the preheating ring 9, they may be configured to extend to a position on the susceptor 7 before the mounting portion 7a. Further, the interval between the adjacent guide plates is narrowed with respect to the susceptor 7 side, but the interval may be constant. The shape, dimensions, mounting attitude, number of installations, and the like of such guide plates may be appropriately set according to the film thickness distribution characteristics of the thin film formed on the surface of the wafer W.

Although the film forming apparatus of the above embodiment is an epitaxial growth apparatus having a preheating ring, the present invention is also applicable to an epitaxial growth apparatus having no preheating ring. The present invention is also applicable to a film forming apparatus other than the epitaxial growth apparatus, for example, a CVD apparatus.

[0025]

According to the present invention, a guide member for guiding the reaction gas introduced into the processing chamber to the surface of the object to be processed is provided, so that not only the flow rate of the reaction gas but also the direction in which the reaction gas flows can be controlled. Since the control can be performed, the uniformity of the film thickness distribution of the thin film formed on the wafer surface is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing an epitaxial growth apparatus which is a film forming apparatus according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a plan sectional view showing an example of a conventional epitaxial growth apparatus.

4A is a diagram showing an example of a film thickness distribution of a thin film formed on a wafer surface, and FIG. 4B is a diagram showing a film when a thin film is formed on a wafer using the epitaxial growth apparatus shown in FIG. It is a figure showing thickness distribution.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Epitaxial growth apparatus (film-forming apparatus), 2 ... Processing chamber, 3a-3e ... Gas supply port, 7 ... Susceptor (wafer support member), 7a ... Placement part, 9 ... Preheating ring (heating member), 10 ... Side walls, 11a to 11f: guide plate (guide member), W: wafer (object to be processed).

Continuing on the front page (72) Inventor Youji Takagi 14-3 Shinzumi, Narita-shi, Chiba Pref. Within Applied Materials Japan Co., Ltd. (72) Inventor Yasuji Arima 14-3 Shin-izumi, Narita-shi, Chiba Pref. F-term (reference) 4K030 AA03 AA06 BA29 BB02 EA03 FA10 GA02 KA12 KA25 5F045 AA03 AB02 AC05 AF02 BB02 DP04 EF14 EK07 EK11 GB01

Claims (3)

[Claims] 1. A film forming apparatus for forming a film by introducing a reaction gas into a processing chamber, flowing the gas along a surface of an object to be processed, and performing a thermal decomposition reaction, wherein the film is introduced into the processing chamber. A film forming apparatus including a guide unit for guiding the reaction gas to the surface of the target object; 2. A processing chamber having a gas supply port, and a wafer support member provided in the processing chamber and having a mounting portion on which an object to be processed is placed, wherein a reaction gas is supplied from the gas supply port to the processing chamber. A film forming apparatus configured to form a film by introducing into a chamber, flowing along a surface of the object to be processed, and causing a thermal decomposition reaction, wherein the film processing apparatus extends from the gas supply port toward the mounting unit, and performs the processing. A film forming apparatus including a guide member for guiding the reaction gas introduced into the chamber to the surface of the target object; 3. A heating member for heating the reaction gas introduced from the gas supply port is provided outside the wafer support member in the processing chamber, and the heating member is provided above the heating member. 3. The film forming apparatus according to claim 2, further comprising a guide member.