JPH05230650A - Substrate holder and production thereof - Google Patents

Abstract

PURPOSE:To form a film uniformly over the entire surface of a substrate surface at the time of forming this film on the surface of the substrate by an OMVPE method, vacuum vapor deposition method, sputtering method, etc. CONSTITUTION:The entire surface of the surface of a base plate 2 is first polished to form a flat polished surface, and thereafter the same material as the material of the base plate 2 or a material having the same coefft. of thermal expansion as the coefft. of thermal expansion of the base plate is formed by a method, such as vapor deposition, sputtering or plating, on the peripheral edge of the polished surface. The substrate 5 is imposed on the polished surface in the case of formation of the film on the surface of the substrate 5. The surface 3 to be imposed with the substrate 5 is the polished surface at this time and, therefore, the surface having high flatness is obtd. The entire part of the rear surface of the substrate 5 imposed thereon is eventually brought into uniform contact with the polished surface of the substrate holder. Consequently, the substrate 5 is thermally uniformalized over the entire part thereof and the film is formed uniformly over the entire surface of the substrate surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate holding device and a substrate holding device for holding a substrate when a film is formed on the surface of the substrate by a metal organic chemical vapor deposition (OMVPE) method, a vacuum deposition method, a sputtering method or the like. It relates to a manufacturing method.

[0002]

2. Description of the Related Art A substrate is an OMVPE apparatus, a vacuum deposition apparatus,
When a film is formed on the surface of the substrate by installing it inside a sputtering device or the like, the substrate is placed on a substrate holding device (a table called a susceptor). This substrate holding device is made of a material having a high thermal conductivity such as molybdenum, and heats or cools the substrate placed thereon.

For example, as shown in FIG. 2, in a conventional substrate holding device 6, a portion (placement surface) 8 on which a substrate is placed is placed in the center of the surface of a base 7 which is generally disc-shaped. It is formed and the periphery is a projecting surface (projecting surface) 9 (that is, the mounting surface 8 is a recessed surface compared to the peripheral edge).
As shown in FIG. 3, the substrate 5 is placed on the placement surface 8. When the substrate 5 is mounted on the mounting surface 8 in this manner, the height of the projecting surface 9 and the height of the substrate 5 are made substantially the same, so that the gas flows uniformly on the substrate 5. Has been That is, if the height of the substrate 5 and the height of the projecting surface 9 are not the same, the gas does not flow uniformly on the substrate 5 and turbulent flow occurs, and a uniform thin film cannot be grown on the substrate 5. Because it will be.

Then, the substrate holding device 6 having such a shape
In the related art, the conventional method is manufactured by cutting the surface of the base 7 made of an appropriate material to form a recess in the center and using this recess as the mounting surface 8.

[0005]

However, the conventional substrate holding device has a problem that a film cannot be uniformly formed on the substrate. That is, since the projecting surface 9 is formed around the mounting surface 8 on which the substrate 5 is mounted and the mounting surface 8 is a concave surface, the mounting surface 8 cannot be polished,
It is difficult to secure sufficient flatness. As a result, the entire back surface of the substrate 5 mounted on the mounting surface 8 does not come into contact with the mounting surface 8, but only partially. Therefore, particularly in the case of OMVPE or the like having a strong temperature dependency, a large difference occurs in the film growth state between the portion where the substrate 5 is in contact with the substrate holding device 6 and the portion where it is not in contact.

For example, when an InGaAs film or an InGaAsP film is grown on an InP single crystal substrate by the OMVPE method, TMI (trimethylindium), T
EG (triethylgallium) and hydride gas (eg PH ₃ ; phosphine, AsH ₃ ; arsine)
Since the thermal decomposition rate of an organic metal (MO) material or the like used for film growth such as is different depending on the temperature, good film growth can be normally performed in a portion where the substrate is in contact with the holding device, but non-contact is possible. In the portion, for example, In _1-X Ga _X As _Y P
The composition of the film changes such that X and _Y in _1-Y change.

In view of the above, an object of the present invention is to provide a substrate holding device improved so that a film can be uniformly formed on a substrate.

Another object of the present invention is to provide a manufacturing method capable of easily manufacturing the above substrate holding device.

[0009]

In order to achieve the above object, in the substrate holding device according to the present invention, the substrate mounting surface made of a polishing surface provided on the surface of the base and the periphery thereof are It is characterized by having a base and a projecting surface formed by adhering a material whose coefficient of thermal expansion substantially corresponds. Since the surface for mounting the substrate is a polished surface as described above, the flatness is high, and when the substrate is mounted, the entire surface of the back surface of the substrate comes into uniform contact, As a result, a uniform film can be formed.

Further, in this substrate holding apparatus, the entire surface of the base is first polished to form a flat polishing surface, which is used as a substrate mounting surface, and then the peripheral edge of the polishing surface is formed. It is manufactured by forming the projecting surface by a method such as vapor deposition, sputtering, and plating. Rather than forming a concave mounting surface by cutting as in the past, it is easy to flatten the mounting surface because the entire surface of the base is polished flat and then the protruding surface is formed on the periphery. Therefore, it is possible to more easily manufacture the substrate holding device capable of forming a uniform film.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an embodiment of the present invention. As shown in FIG. 1, a substrate holding device 1 according to an embodiment of the present invention is manufactured by polishing the entire surface of a base 2. The mounting surface 3 is provided, and the protruding surface 4 is formed on the periphery of the mounting surface 3 by adhering the same material as the base 2 or a material having the same thermal expansion coefficient.

The base 2 is made of a material having good thermal conductivity such as molybdenum, tungsten, carbon (graphite), etc., and has a disc shape as a whole as shown in FIG.

First, the entire surface of the base 2 is sufficiently polished to form a flat polished surface on the entire surface.

Next, the same material as that of the base 2 or a material having the same coefficient of thermal expansion as that of the base 2 is adhered to the peripheral edge of the polished surface of the base 2 by a method such as vapor deposition, sputtering or plating, and thus the protruding surface 4 is formed. To form. The height of the projecting surface 4 is set to be the same as the thickness of the substrate 5 placed later.
The polishing surface surrounded by the projecting surface 4 becomes the surface (mounting surface) 3 on which the substrate 5 is mounted, and the mounting surface 3 has a shape corresponding to the shape of the substrate 5. Thus, the pattern of the protruding surface 4 is determined. When forming the protruding surface 4 by vapor deposition, sputtering, etc., a suitable mask is formed in conformity with the shape of the mounting surface 3, and then vapor deposition, sputtering, etc. are performed.

Specifically, for example, a disk made of molybdenum having a diameter of 60 mm and a thickness of 5 mm is used as the base 2, and the entire surface of the disk is lapped and then sufficiently polished by polishing or electrolytic polishing. Next, resin (resist etc.) is used as a mask on the center of the polished surface.
Is applied to a circle having a diameter of 50 mm, and molybdenum, which is the same material as the base 2, is attached to a thickness of 0.2 mm by a vapor deposition method. After that, the above mask is removed by etching to form a projecting surface 4 having a thickness of 0.2 mm and a width of 5 mm on the peripheral edge of the surface of the base 2, and a mounting surface composed of a polishing surface surrounded by the projecting surface 4 is formed. Form surface 3.

The substrate 5 is placed on the placing surface 3 of the substrate holding apparatus 1 thus manufactured, and the substrate holding apparatus 1 is placed inside an OMVPE apparatus, a vacuum vapor deposition apparatus, a sputtering apparatus or the like not shown. A film is formed. Then,
Since the mounting surface 3 is a flat polishing surface, the substrate 5 comes into uniform contact with the mounting surface 3 of the substrate holding device 1 over the entire back surface thereof, and there is no contacted portion, The entire substrate 5 is in a thermally uniform state.

As a result, the substrate 5 does not have a temperature difference depending on the location, and the thermal decomposition rate of the material used for film growth can be prevented from varying depending on the location of the substrate 5. Also,
In this way, the protruding surface 4 having a pattern that surrounds the substrate 5 placed on the mounting surface 3 is formed around the substrate 5.
It is formed at the same height as above, and the gas flows uniformly on the surface of the substrate 5 to prevent turbulence and the like from occurring.
Therefore, the composition of the growing film can be made uniform over the entire surface of the substrate 5.

For example, an InP single crystal substrate is used as the substrate 5, and InGaA is formed on the substrate 5 by the OMVPE method.
It is assumed that the sP film (or InGaAs film) is grown. In this case, TMI (trimethylindium), TE
Organometallic (MO) materials such as G (triethylgallium) and hydride gas (eg PH ₃ ; phosphine, AsH ₃ ; arsine) are used as materials for film growth. Although the thermal decomposition rates of these materials differ depending on the temperature, since the entire substrate 5 is in uniform contact with the mounting surface 3 of the substrate holding device 1, the temperature is uniform over the entire surface of the substrate 5, so that the entire surface is good. Various film growths can be performed, and X and Y in the grown In _1-X Ga _X As _Y P _1-Y film become uniform over the entire surface.

[0019]

As described above, according to the substrate holding apparatus of the present invention, a uniform film can be formed on the entire surface of the substrate. Further, according to the method of manufacturing the substrate holding device, it is possible to more easily manufacture the substrate holding device that enables such favorable film formation.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a perspective view of a conventional example.

FIG. 3 is a sectional view of a conventional example.

[Explanation of symbols]

 1, 6 Substrate holding device 2, 7 Base 3, 8 Mounting surface 4, 9 Projection surface 5 Substrate

Claims (2)

[Claims] 1. A substrate mounting surface, which is formed by polishing the entire surface of a base, and a material having a coefficient of thermal expansion substantially corresponding to that of the base are mounted on the substrate mounting surface. And a projecting surface formed by adhering to the peripheral edge of the substrate holding device. 2. A step of polishing the entire surface of the base to form a polishing surface on the entire surface, and then, the peripheral edge of the polishing surface has a coefficient of thermal expansion substantially corresponding to that of the base. A step of forming a projecting surface having substantially the same height as that of the substrate placed on the polishing surface by depositing the deposited material on the polishing surface.