JPH1187251A - Vapor phase growth apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vapor phase growth apparatus with highly precise temperature control. SOLUTION: A vapor phase growth apparatus that forms a vapor phase growth film on a surface of a semiconductor wafer 106 is provided. Therein, a heater 1 that is installed in the back side of the semiconductor wafer 16 and heats the wafer 16, a space control means 36, and others to control a space between the wafer 106 and a heater 1 are included. The heater 1 comprises a plurality of split heater parts and provides a power supply control means to individual power supplies of the heater parts.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vapor-phase growth apparatus, and more particularly to a single-wafer-type vapor-phase growth apparatus for performing epitaxial vapor-phase growth on the surface of a semiconductor wafer.

[0002]

2. Description of the Related Art An epitaxial growth apparatus for forming a layer on a surface of a semiconductor wafer by epitaxial growth includes:
There are a batch processing type in which a large number of semiconductor wafers are collectively processed, and a single-wafer processing type in which semiconductor wafers are processed one by one.

[0003] Batch type epitaxial devices have the advantage of high productivity and therefore high throughput. On the other hand, the single-wafer type epitaxial apparatus has an advantage that the thickness of a layer formed by epitaxial growth can be controlled uniformly and with high accuracy over the entire surface of a semiconductor wafer.

In recent years, semiconductor elements have been increasingly integrated, and accordingly, epitaxial growth techniques also require that the thickness of the grown layers be controlled uniformly and with high precision over the entire surface of the substrate. ing. Also, in order to improve the material efficiency of the semiconductor wafer, the diameter of the semiconductor wafer has been increased.

In order to realize these, the epitaxial growth apparatus has shifted its technical importance from the conventional batch processing type to the single-wafer processing type. This is the same in an apparatus generally applied to a vapor phase growth apparatus including CVD.

The key point in the single-wafer processing type is that
It is about throughput. In order to improve the throughput, shortening the heating or cooling time and shortening the transport time of the semiconductor wafer and increasing the epitaxial growth rate can be considered. Particularly, in the latter case, the semiconductor wafer is rotated at a high speed of several hundred rotations or more. As a result, the reaction gas is attracted to the semiconductor wafer surface (pump effect),
The boundary layer immediately above the semiconductor wafer surface where the epitaxial growth reaction proceeds is thinned to increase the reaction gas supply efficiency to increase the growth rate. Note that SiH ₄ , SiH ₂ Cl ₂ or the like is generally used as the reaction gas.

In addition, the pressure inside the reaction furnace is controlled to reduce auto-doping from the semiconductor wafer, and the flow of the reaction gas is adjusted to prevent an increase in particles due to the influence of stagnation or the like.

FIG. 3 shows a schematic configuration of a basic single wafer type vapor phase growth apparatus.

The gas supply port 10 at the upper part of the vapor growth chamber 101
The reaction gas is passed through the rectifying plate 103 from the
The semiconductor wafer 106 is introduced from the semiconductor wafer inlet 104 into the susceptor 105 serving as a support table. The semiconductor wafer 106 is susceptor 1
A rotating device 11 such as a motor around the rotating shaft 107 along with 05
2 to rotate the heater 108 to the radiation thermometer 109
The semiconductor wafer 106 is heated to a predetermined temperature while controlling the temperature, and a film is formed on the surface of the semiconductor wafer. The reaction gas is supplied to an exhaust port 1 provided at a lower part of the vapor phase growth chamber 101.
The air is evacuated from a dry pump (not shown). A cylindrical quartz reaction tube 121 is provided inside an outer wall 120 of the vapor phase growth chamber 101, and an inner quartz ring 122 is coaxial with the quartz reaction tube 121 so as to surround the susceptor 105 on the inner diameter side. Is provided.

FIG. 4 schematically shows the flow of the reaction gas in the vapor phase growth chamber.

Reaction gas 125 introduced from the upper part of the reactor
Reaches the surface of the semiconductor wafer 106, is extruded in the outer peripheral direction, and extends along the tube wall of the quartz reaction tube 121.
Go to 10.

[0012]

In such a single wafer type vapor phase epitaxy apparatus, the heat source for heating the semiconductor wafer 106 is to enable rapid temperature rise and fall, In order to have a structure without obstacles so as not to disturb the flow of the reaction gas 125, a resistance heater 108 made of C (carbon) coated with SiC directly from the back surface of the semiconductor wafer 106 is used.

In this case, in holding the semiconductor wafer 106, the outermost peripheral portion of the semiconductor wafer 106 is about 2 mm.
The approximately wide portion is supported by a C susceptor counterbore portion 105a coated with SiC. The portion of the semiconductor wafer 106 that contacts the susceptor counterbore portion 105a is heated through the susceptor 105, and tends to be insufficiently heated. For this reason, it is difficult to uniformly heat the entire semiconductor wafer 106 using a single heater. In particular, the susceptor counterbore 105a
It is difficult to uniformly heat the entire surface of the semiconductor wafer with a single heater including a portion that contacts the semiconductor wafer.

For this reason, as shown in FIG. 6, the heater 108 comprises a disc-shaped portion 131 arranged concentrically from the center and a donut-shaped portion 132, 133, 134, 134, 13 outside the disc-shaped portion.
5, 136, and each part was independently temperature-controlled by electric power.

FIG. 6A shows the front surface of the conventional heater 108, and FIG. 6B shows the back surface of the heater 108. FIG. 5 is a cross-sectional view taken along line AA ′ in FIG.

As shown in FIG. 5 and FIG. 6 (b), perpendicularly to the plane of the drawing, six heater supporting plates 1 made of insulating material, for example, made of quartz.
Reference numeral 38 stands upright on the disk flat plate 139. On the heater support plate 138, a disk-shaped part 131 and a donut-shaped part 132,
133, 134, 135 and 136 are fixedly mounted. Further, the disk-shaped portion 131 and the donut-shaped portions 132, 13
Electrode stands 131a, 132 in which conductive wires for supplying power to each of 3, 134, 135, 136 are delivered.
a, 133a, 134a, 135a, and 136a are provided on a disk 139 perpendicular to the plane of the paper. Electrode table 13
1a, 132a, 133a, 134a, 135a, 13
Each of the electrodes 6a is coupled to a plurality of electrode rods 140a and the like at the center.

As shown in FIGS. 5 and 6, in the conventional heater 108, a disk-shaped portion 131, a donut-shaped portion 132,
133, 134, 135 and 136 are heater support plate 1
38, and is set at a fixed distance from the surface of the semiconductor wafer 106.

With such a conventional heater 108,
The in-plane variation of the epitaxial growth layer thickness is, for example, 15
In the case of the semiconductor wafer 106 having a diameter of 0 mmφ, the thickness of the epitaxial growth layer is set to 1.95 to 2.05 with the aim of 2 μm.
It could be controlled at μm, and could be epitaxially grown with an accuracy of about 5%.

However, there is a demand for further miniaturization and higher integration of semiconductor devices. In order to satisfy the demand and to improve the uniformity of the product characteristics and the yield, the epitaxial growth layer has a higher flatness. In order to realize this, an apparatus structure that can be further fine-tuned with respect to the temperature control of the vapor phase growth apparatus has been required.

An object of the present invention is to solve the above-mentioned problems of the prior art and to provide a vapor phase growth apparatus capable of controlling the temperature with high accuracy.

[0021]

In order to achieve the above object, the present invention provides a vapor growth apparatus for forming a vapor growth film on a surface of a semiconductor wafer. And a heater for heating the semiconductor wafer, and an interval control means for controlling an interval between the surface of the semiconductor wafer and the heater.

The heater comprises a plurality of divided heater portions, and is provided with a supply power control means for controlling power supplied to these heater portions independently of each other.

The distance control means includes a holding member for holding the heater on one side, and an elevating control means for elevating the other side of the holding member with respect to the surface of the semiconductor wafer.

The heater comprises a plurality of divided heater parts, and comprises a supply power control means for controlling the power supplied to these heater parts independently of each other. The interval control means comprises: A plurality of sets each including a set of at least three holding members for holding at least three points, and lifting control means for controlling lifting and lowering of each of the plurality of sets independently of each other with respect to the surface of the semiconductor wafer. , Is provided.

The elevation control means controls the elevation of the respective sets of holding members with respect to the surface of the semiconductor wafer so that each of the heater portions is moved up and down while being maintained parallel to the surface of the semiconductor wafer. And

The set of holding members comprises three holding members, and the elevation control means moves up and down while maintaining each of the heater portions in parallel with the surface of the semiconductor wafer.
It is characterized in that each set of the holding members is controlled to move up and down with respect to the surface of the semiconductor wafer.

[0027] The elevation control means may independently control elevation of each of the holding members constituting the set of each of the plurality of sets with respect to the surface of the semiconductor wafer.

The set of holding members is characterized by comprising four or more holding members.

One side of the holding member for holding the heater is made of a member coated with SiC.

An atmosphere near the holding member and an atmosphere near the heater are partitioned between the heater and the holding member, which is a part of the holding member that is controlled to be moved up and down by the elevation control means. And a partition plate for providing the same.

The present invention is characterized in that N 2 gas is sent to the atmosphere near the holding member.

In the above-mentioned invention, the present invention operates as follows.

Since the vapor phase growth apparatus of the present invention is provided with interval control means for controlling the interval between the surface of the semiconductor wafer and the heater, in addition to controlling the heater electrically, the surface of the semiconductor wafer and the heater are controlled. By controlling the interval between the heaters, the position of the heater can be spatially controlled, and highly accurate temperature control can be performed.

The heater is composed of a plurality of divided heater portions and is provided with supply power control means for controlling the power supplied to these heater portions independently of each other. In addition to control,
By controlling the space between the surface of the semiconductor wafer and the heater and spatially controlling the position of the heater, high-precision temperature control can be performed.

Each of the plurality of divided heater portions is held at at least three points by at least three holding members, and the set of the holding members is controlled independently of each other by the lifting control means. In this case, one set of the holding members is integrally controlled to move up and down, and the other sets can be controlled to move up and down independently of each other.Moreover, in each of the holding members forming one set of the holding members, Can be controlled independently of each other.

In the case of holding at three points, since one surface is determined by the three points, each of the heater portions is supported by one plane.

When holding at four or more points, the surface supporting the heater portion may not be a single plane, but in this case, for example, non-uniform vapor phase growth on the surface of the semiconductor wafer occurs. Also in the case of obtaining, the heater portion can be distributed on the curved surface to avoid non-uniform vapor phase growth on the surface of the semiconductor wafer.

One side of the holding member for holding the heater is made of SiC.
By configuring with a member coated with, to avoid generation of dust from the holding member on the side close to the semiconductor wafer,
It is possible to prevent contamination by metal impurities contained in the carbon material and the like.

By providing a partition plate between the heater and the holding member portion, which is a portion of the holding member that is controlled to be lifted and lowered by the lifting control means, the holding member portion, which is a portion where dust and the like are likely to be generated, It is possible to prevent dust and the like from moving to the vicinity of the semiconductor wafer or the heater.

By sending the N 2 gas to the atmosphere near the holding member portion, it is possible to prevent dust and the like from moving from the holding member portion, which is a portion where dust and the like are likely to be generated, to the vicinity of the semiconductor wafer or the heater. it can.

[0041]

Embodiments of the present invention will be described below with reference to the drawings.

The vapor phase growth apparatus according to the present invention has substantially the same configuration as that of the apparatus shown in FIG. 3 except for the heater, so that the description of the overlapping part will be omitted, and the heater will be described in detail. .

FIG. 1 is a sectional view for explaining a heater 1 in a vapor phase growth apparatus according to the present invention. Heater 1
A susceptor 105 is disposed above the susceptor 105, and a semiconductor wafer 106 is mounted on the susceptor 105. The susceptor 105 is attached to the upper end of the rotating frame 3 that rotates around the rotation axis 5.
The semiconductor wafer 106 on 05 rotates together with the susceptor 105 around the rotation axis 5 integrally with the rotating frame 3. The rotating frame 3 is rotated by a rotating device 7 such as a motor. The upper part of the rotary frame 3 has a large diameter cylindrical shape and the heater 1 and the like are delivered, and the lower part has a small diameter cylindrical shape and is connected to a rotating device.

Hereinafter, the heater 1 will be described in detail with reference to FIGS.

FIG. 2A shows the surface of the heater 1, and FIG.
(B) shows the back surface of the heater 1. FIG. 2 is a cross-sectional view taken along line BB′-B ″ in FIG.

The heater 1 is made of carbon and coated with SiC.

As shown in FIG. 2, the heater 1 has a rotation axis 5
And a donut-shaped part 12, 13, 14, 15, 16 disposed in a ring shape outside of the disk-shaped part 11 having the center axis as a central axis.

The disk-shaped part 11 and the donut-shaped part 1 of the heater 1
Each of 2, 13, 14, 15, 16 includes a heater holding member 21, 22, 23, 24, 25, 26 and a heater holding auxiliary member 21a, 21a, 22a, 22a, 23a, 23.
a, 24a, 24a, 25a, 25a, 26a, 26a
Supported by

The heater holding members 21, 26 and the heater holding auxiliary members 21a, 21a, 26a, 26a are shown in FIG.
(B) has a shape extending in a direction perpendicular to the paper surface.
For example, the heater holding member 21 and the heater holding auxiliary member 21
Since a and 21a are located at the center, they have a columnar shape extending in a direction perpendicular to the plane of FIG. 2B. The heater holding members 22 have an L-shape extending in the direction perpendicular to the plane of the drawing in FIG. The heater holding member 21 is configured by arranging two conductive columnar members such as carbon materials in parallel with a small gap. Each of the heater holding members 22... 26 is configured by arranging two conductive L-shaped members such as carbon materials in parallel with a small gap. Two columnar members and two L
The letter-shaped member functions as an electric wire itself for supplying a current to the heater 1, one end is connected to the heater 1, and the other end is provided with two Mo shafts disposed inside a lifting shaft 36 described later. Connected to the body. Note that the heater holding members 21 to 26 may be members other than carbon materials as long as they are high-temperature resistant and conductive. Heater holding auxiliary members 22a, 22a... 26
Reference numerals a and 26a are composed of electrically insulating members.

As shown in FIG. 2B or FIG. 1, the heater holding members 21...
, 26a and 26a are disposed so as to face the center axis 5, and the disk-shaped portion 11 and the donut-shaped portion 1
6 are supported at three points. Since each of the heater holding members 21... 26 is constituted by two columnar members or two L-shaped members as described above, it is not necessarily supported at one point with the heater portion. ,
Since they are arranged side by side with a small gap, they are approximately regarded as one point.

In FIG. 1, only the heater holding member 26 and the heater holding auxiliary member 26a are shown by solid lines, and the others are shown by dotted lines or omitted.

As shown in FIG. 1, the L-shaped upper end of each of the heater holding member 26 and the heater holding auxiliary members 26a, 26a supports the donut-shaped portion 16. Upper end of heater holding member 26 and heater holding auxiliary members 26a, 26a
The three end portions of the upper end portion form one plane, and this plane becomes a heater part mounting surface. In the embodiment described below, the heater portion mounting surface is not limited to a plane, but is a plane determined by three points in the present embodiment. Heater holding member 26
Is fixed on the heater part mounting surface. Here, the heater part mounting surface such as the heater holding member 26 is set to be parallel to the surface of the semiconductor wafer 106.

The ends of the L-shaped bottoms of the auxiliary heater holding members 26a, 26a are covered with an electrical insulating material which is one of six elevating shafts arranged around the rotation axis 5. It is connected to a lifting shaft 36. The ends of the bottoms of the two L-shaped members of the heater holding member 26 are connected to respective Mo shafts disposed in the elevating shaft 36. Elevating shaft 3
As the wafer 6 moves up and down, the heater holding member 26 on the heater part mounting surface moves up and down in parallel with the surface of the semiconductor wafer 106.

Although the other five elevating shafts are not shown in FIG. 1, each of the elevating shafts is provided with a heater holding auxiliary member 2.
The end of the L-shaped bottom of each of 1a... 25a is connected. The bottom end of each of the heater holding members 21... 25 is connected to a shaft made of Mo provided in each elevating shaft. As the elevating shaft moves up and down, the corresponding heater portion on the heater portion mounting surface moves up and down in parallel with the surface of the semiconductor wafer 106.

One end of each of the two L-shaped members constituting the heater holding member 26 is connected to the donut-shaped portion 16 at 16a, 16a, and the other end is provided with an M provided inside the elevating shaft 36.
It is connected to one end of a shaft made of o. The other end of the Mo shaft is connected to the power control device 9. Electric power is also supplied to the other heaters by the Mo shaft connected to the power control device 9 and passing through the corresponding elevating shaft.
The power control device 9 is connected to the control unit 34, and the power control device 9 is controlled by receiving a command such as temperature control from the control unit 34, whereby the disc-shaped portion 131, the donut-shaped portions 132, 133, 134 , 135, and 136 are independently controlled.

A gear 37 having a predetermined length is fixed to the elevating shaft 36. A gear 38 meshing with the gear 37 is provided near the gear 37. The gear 38 is supported by a gear support member 39 fixed to the apparatus main body, and is rotationally controlled by a step motor 35. When the gear 38 is rotated by the step motor 35, the gear 38
The elevating shaft 36 moves up and down via a gear 37 meshing with the shaft. When the elevating shaft 36 moves up and down, the heater holding member 26 and the heater holding auxiliary member 26a coupled to the elevating shaft 36 move up and down, the donut-shaped portion 16 moves up and down, and the space between the donut-shaped portion 16 and the surface of the semiconductor wafer 106 is increased. The interval is adjusted.

Similarly, the other elevating shafts (not shown) are configured to be controlled independently of each other by other stepping motors, so that the disk-shaped portion 11, the donut-shaped portions 12, 1
The distances between 3, 14, 15 and the surface of the semiconductor wafer 106 are adjusted independently of each other. Step motor 35
Are connected to the control unit 34, and a plurality of step motors such as the step motor 35 are controlled by receiving control commands such as temperature control from the control unit 34.

As described above, the outer peripheral portion of the semiconductor wafer 106 having a width of about 2 mm is supported by the susceptor counterbore portion 105a.
06, the portion that contacts the susceptor counterbore portion 105a
Since the heating is performed through the susceptor 105, the heating tends to be insufficient.
It is not easy to uniformly heat the entire surface of the semiconductor wafer 106 including the portion in contact with 5a.

Therefore, in the present invention, the power controller 9 controls the disk-shaped portion 131 and the donut-shaped portions 132.
In addition to independently controlling the power supplied to each of the heater portions 36, a disk-shaped portion 131, a donut-shaped portion 132
The spatial distance between each heater portion 136 and the surface of the semiconductor wafer 106 is adjusted independently of each other.

In the example shown in FIG. 1, the susceptor counterbore unit 1
The gap between the donut-shaped portion 16 located below the area 05a and the surface of the semiconductor wafer 106 is adjusted to be the smallest, and the gap between another heater portion and the surface of the semiconductor wafer 106 is adjusted so as to be distributed in a mountain-valley shape. I have. These intervals are adjusted based on experimental data so that the temperature distribution in the plane of the semiconductor wafer 106 becomes the most uniform. These spatial intervals can be fixedly set over the entire process of vapor phase growth of the thin film on the surface of the semiconductor wafer 106, and can be set according to the vapor phase growth process or at ambient temperature. It is also possible to change over time according to it.

In the upper part of the rotary frame 3, a first disc-shaped partition plate 41 is disposed below the heater 1 in order to prevent the heat of the heater 1 from being transmitted downward.
Below the partition plate 41, a disk-shaped second partition plate 42 with a support shaft 42a is disposed. The first partition plate 41 is supported by a plurality of columns 41a erected on the second partition plate 42.

The support shaft 42a is at a position where the rotation axis 5 is the axis. In the first partition plate 41 and the second partition plate 42,
The heater holding members 21 and 26 and the heater holding auxiliary member 21
A plurality of through holes are formed so as not to hinder the elevating operation of the a, 21a... 26a, 26a, the elevating shaft 36 and the like.

An N 2 gas introduction pipe 44 is provided in the rotation frame 3 near the rotation axis 5 and extends from below in parallel with the rotation axis 5, and N 2 gas as a buffer gas is supplied from the N 2 gas introduction pipe 44 to the semiconductor. It is supplied from the back side of the wafer 106.

The partition plate 41 disposed between the upper end of the elevating shaft 36 and the heater 1 also has a function of suppressing the generation of dust from the movable part such as the functional elevating shaft 36. Further, by exhausting the N2 gas from the N2 gas introduction pipe 44 to a lower exhaust port (not shown), the generation of dust from a movable portion such as the elevating shaft 36 is suppressed.

Next, a comparison result between the embodiment using the heater 1 of the present invention shown in FIGS. 1 and 2 and the conventional example using the conventional heater 108 shown in FIGS. 5 and 6 will be described.

Epitaxial growth was performed in a vapor phase growth chamber and a quartz reaction tube structure of the single wafer type vapor phase growth apparatus shown in FIG.

First, a conventional example will be described. 5 and 6
The epitaxial growth was carried out using a heater 108 which can be divided into six parts as shown in FIG. At this time, the epitaxial growth was carried out by monitoring the surface temperature of the semiconductor wafer 106 with six radiation thermometers 19 and controlling the power so that the in-plane temperature variation was minimized during the temperature rise and during the epitaxial growth. In addition, an interval of 8 mm was maintained between the semiconductor wafer 106 and the heater 108. The heater 108 is a heater electrode base 1 made of C coated with SiC.
36a and the like and a heater support plate 138 made of an insulating material. Electric power is supplied to the heater electrode base 136a and the like via electric wires passing through the inside of the electrode rod 140a and the like coated with insulation.

In this state, a commercially available 150 mm
φ, 625 μm thick semiconductor wafer 106 has a thickness of 2.0
Continuous 250 epitaxially grown layers were formed aiming at μm. The growth condition of the epitaxial growth layer is H ₂ : 3
SiH ₂ Cl ₂ : 100 in an atmosphere in which 0 slm was flowed
sccm, using a reaction gas of B ₂ H ₆ : 30 sccm,
The susceptor 105 is rotated at 2000 rpm, and 115
Growth was performed at 0 ° C. under a reduced pressure of 50 Torr for 4 minutes.

Further, etching was performed by using HCl gas at a rate of once every 50 sheets so that Si deposited on the susceptor or the like could be removed by about 120 μm.

After the completion of the treatment of 250 wafers, the thickness of the epitaxially grown layer was measured for all the semiconductor wafers 106 from the center to 70 mm at a pitch of 5 mm from the center by using a film thickness measuring apparatus using reflection of infrared rays generally used. The in-plane variation was 1.95 to 2.05 μm, and an epitaxial growth layer was formed at about 5%.

Next, an embodiment of the present invention will be described.

Using the heater 1 having the heater structure of the present invention shown in FIGS. 1 and 2, epitaxial growth was carried out in the same manner as described above using a single-wafer-type vapor phase growth apparatus substantially similar to the apparatus shown in FIG. .

The heater 1 is the same as the conventional type,
1. The heater parts of the donut-shaped parts 132... 136 are divided into six parts, and the supply power of each heater part is controlled independently. Each heater portion has a structure in which the elevating shaft 36 and the like can be moved up and down by a step motor 35 at a pitch of 10 μm.

For the temperature control by the heater 1, the control unit 34 uses the time interval in which the power control unit 9 rewrites the data of the power supplied to each heater part in response to the instruction from the control unit 34, and A signal was also sent to 35 to adjust the elevating distance of the elevating shaft 36 and the like. As a result, the temperature control by the supplied power and the temperature control by adjusting the spatial interval between each heater portion and the semiconductor wafer 106 allow finer control by the two temperature adjusting mechanisms. Under this, epitaxial growth was performed.

As a result, in the example of the present invention, an epitaxial growth layer was formed on 250 semiconductor wafers 106 under the same conditions as in the conventional case, and the in-plane variation was 1.98 to 2.00 μm. , About 1%, an epitaxially grown layer was formed. Further, the number of particles attached to the surface of the semiconductor wafer 106 was about several, and there was no particular problem.

As described above, according to the embodiment of the present invention, the conventional epitaxially grown layer thickness is ± 5% of the target value.
%, But could be suppressed to ± 1.5%. As a result, it has become possible to manufacture a device that requires high flatness and requires further fine processing.

As described above, according to the embodiment of the present invention, the disk-shaped portion 11 of the heater 1 and the donut-shaped portions 12, 13, 14, 1
In addition to independently controlling the temperature of each of the heaters 5 and 16 in terms of electric power, the disk-shaped portion 11 and the donut-shaped portion 12 of the heater 1
13, 14, 15, 16 and the semiconductor wafer 106
, The space between the heater 1 and the semiconductor wafer 106 can be introduced as a parameter for temperature control. Temperature can be controlled with high accuracy.

As a result, the temperature rise loss at the contact portion with the susceptor, the influence from the outer wall of the reactor, etc. can be eliminated, the temperature can be adjusted more finely, and the conventional epitaxially grown layer has a thickness of ± 5% of the target value. The variation was within ±
It could be suppressed up to 1.5%.

As a result, it is possible to provide a semiconductor wafer that can be applied to a device requiring high flatness, which requires further fine processing.

Further, by controlling the heater holding member 26 and the like and the heater holding auxiliary members 26a and 22a and the like by one elevating shaft 36 and the like, the heater portion such as the donut-shaped portion 16 and the like is flat with respect to the surface of the semiconductor wafer 106. It can be held up and controlled up and down.

Next, another embodiment of the present invention will be described.

In the above embodiment, the heater holding member 2
6 is set to be a plane parallel to the surface of the semiconductor wafer 106, and the heater holding member 26 is maintained on a plane parallel to the surface of the semiconductor wafer 106 as the elevating shaft 36 moves up and down. It was configured to go up and down. The same applies to other heater parts.

On the other hand, in the embodiment described below, the heater portion mounting surface on which the heater holding member 26 is mounted is not limited to be parallel to the surface of the semiconductor wafer 106, and an inclined direction can be selected in any direction. Further, the heater holding member 26 is mounted on a curved heater part mounting surface, and the heater holding member 26 is configured to be able to take a curved surface shape.

For this purpose, for the heater holding member 26, one heater holding member 26 and three heater holding auxiliary members 26 distributed at an angular interval of 90 degrees with respect to the heater holding member 26.
a, 26a, 26a are provided. The heater holding member 26 is held at the upper ends of a total of four members, one heater holding member 26 and three heater holding auxiliary members 26a, 26a, 26a, and can be inclined with respect to the surface of the semiconductor wafer 106. It can take a curved shape. The amount by which the other point protrudes from the plane determined by the three points is at most a few mm, and with this degree, the heater holding member 26 can easily take a curved shape.

The one heater holding member 26 and the three heater holding auxiliary members 26a, 26a, 26a are respectively connected to four separate lifting / lowering shafts, and these four lifting / lowering shafts are independent of each other. It is configured to be controlled to move up and down. Similarly, each of the other heater portions is controlled to move up and down by four lifting shafts.

According to the present embodiment, the following effects can be obtained.

Since the height of each of the heater portions such as the heater holding member 26 can be independently adjusted at four points, the heater holding member 26 and the like can have a curved surface shape. Etc. and semiconductor wafer 1
It is possible to two-dimensionally adjust and control the spatial distance from the control unit 06. As a result, it is possible to control the temperature in the epitaxial growth with higher precision.

For example, in the case where the thickness variation of the epitaxial growth layer occurs on the left and right sides with the crystal axis direction passing through the center of the wafer 106 indicated by the orientation flat of the semiconductor wafer 106 as the axis of symmetry, the position closest to the location where the variation occurs By operating the vertical shaft at the position up and down, variations can be suppressed.

In this case, one heater portion is moved up and down by four elevating shafts. However, by controlling the up and down movement of one heater portion by more than four elevating shafts, the heater holding member 26 and the like can be controlled. It is possible to further finely adjust the spatial distance from the semiconductor wafer 106 two-dimensionally.

In the above description, a single wafer type vapor phase growth apparatus has been described as an example of a vapor phase growth apparatus. However, the present invention is not limited to a single wafer type vapor phase growth apparatus, but may be applied to a batch processing type phase growth apparatus. It is also applicable.

[0091]

As described above, according to the structure of the present invention, since the interval control means for controlling the interval between the surface of the semiconductor wafer and the heater is provided, the interval between the surface of the semiconductor wafer and the heater is controlled. It is possible to provide a vapor phase growth apparatus that can be used as a parameter to control the temperature with high accuracy.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a heater divided into a plurality of heater portions and a heater elevation control means in a vapor phase growth apparatus of the present invention.

FIG. 2 is a diagram showing a front surface (a) on the semiconductor wafer side of a heater and a back surface (b) thereof in the vapor phase growth apparatus of the present invention.

FIG. 3 is a sectional view showing a schematic configuration of a general vapor phase growth apparatus.

FIG. 4 is a sectional view showing the vicinity of a susceptor in FIG. 3;

FIG. 5 is a diagram showing a schematic configuration of a heater divided into a plurality of heater portions in a conventional vapor phase growth apparatus.

FIG. 6 is a diagram showing a front surface (a) on the semiconductor wafer side of a heater and a back surface (b) thereof in a conventional vapor phase growth apparatus.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Heater 3 Rotation frame 5 Rotation axis 9 Power control device 11 Disc-shaped part (heater part) 12, 13, 14, 15, 16 Donut-shaped part (heater part) 21, 22, 23, 24, 25, 26 Heater holding Members 21a, 21a, 22a, 22a, 23a, 23a, 2
4a, 24a, 25a, 25a, 26a, 26a Heater holding auxiliary member 34 Control unit 35 Step motor 36 Elevating shaft 37, 38 Gear 39 Gear supporting member 41 First partition plate 42 Second partition plate 44 N2 gas inlet tube 105 Susceptor 105a Susceptor Counterbore 106 Semiconductor wafer

Claims (11)

[Claims] 1. A vapor deposition apparatus for forming a vapor deposition film on a surface of a semiconductor wafer, comprising: a heater disposed on the back side of the semiconductor wafer for heating the semiconductor wafer; An interval control means for controlling an interval. 2. The heater according to claim 1, wherein the heater comprises a plurality of divided heater portions, and a supply power control means for controlling power supplied to these heater portions independently of each other. Vapor phase growth equipment. 3. The distance control means includes: a holding member that holds the heater on one side; and a lifting control means that controls lifting and lowering of the other side of the holding member with respect to a surface of the semiconductor wafer. The vapor phase growth apparatus according to claim 1, wherein 4. The heater comprises: a plurality of divided heater portions; and a supply power control means for controlling power supplied to these heater portions independently of each other; And a plurality of sets each including at least three holding members each holding at least three points, and a lifting and lowering unit that independently controls lifting and lowering of each of the plurality of sets with respect to a surface of the semiconductor wafer. The vapor phase growth apparatus according to claim 3, further comprising: a control unit. 5. The elevation control means controls the elevation of each set of holding members with respect to the surface of the semiconductor wafer such that each of the heater portions is moved up and down while being maintained in parallel with the surface of the semiconductor wafer. The vapor phase growth apparatus according to claim 4, wherein: 6. The set of holding members comprises three holding members, and the elevation control means controls each of the heater portions such that each of the heater portions is moved up and down while being maintained in parallel with the surface of the semiconductor wafer. The vapor phase growth apparatus according to claim 5, wherein the set of holding members is controlled to move up and down with respect to the surface of the semiconductor wafer. 7. The elevation control means independently controls elevation of each of the plurality of holding members constituting each of the plurality of sets of holding members with respect to a surface of a semiconductor wafer. The vapor phase growth apparatus according to claim 4, wherein 8. The vapor phase growth apparatus according to claim 7, wherein said set of holding members comprises four or more holding members. 9. The vapor phase growth apparatus according to claim 3, wherein one side of the holding member for holding the heater is formed of a member coated with SiC. 10. An atmosphere in the vicinity of the holding member and an atmosphere in the vicinity of the heater, between the holding member and the heater, the holding member being a part of the holding member that is controlled to be moved up and down by the elevation control means. 4. The vapor phase growth apparatus according to claim 3, wherein a partition plate for partitioning is provided. 11. An atmosphere in the vicinity of the holding member portion includes N2.
The gas phase growth apparatus according to claim 10, wherein gas is sent.