JPH0586643B2 - - Google Patents

Description

Detailed Description of the Invention (a) Technical Field of the Invention The present invention relates to a reaction tube, a partition wall that extends inside the reaction tube and divides the inside of the reaction tube into a plurality of reaction chambers, and a plurality of different semiconductor layers on the partition wall. a substrate to be vapor-phase grown;
It belongs to the field of a vapor phase growth apparatus for a plurality of different semiconductor layers, which includes gas pipes that supply different types of reaction gases to the plurality of growth chambers, and gas intake pipes that take in the reaction gas in the reaction tubes.

(b) Prior Art Conventionally, this type of vapor phase growth apparatus for forming a plurality of different semiconductor layers has been described, for example, in Japanese Patent Laid-Open No. 52-96865.

This vapor phase growth apparatus consists of an area in which the interior of the reaction tube is divided into a plurality of growth chambers by a partition wall, and an undivided area on the downstream side of the gas flow for substrate movement. There is. Further, the substrate holder that holds the substrate is provided at the tip of a rod-shaped member that is freely inserted and removed from the downstream side of the gas flow.

This vapor phase growth apparatus operates the rod-shaped member to pull out the substrate holder inserted into one of the growth chambers to the undivided area, and then inserts it into the other growth chamber. This is used to move substrates between growth chambers.

(c) Problems to be Solved by the Invention In the above-mentioned conventional vapor phase growth apparatus for forming a plurality of different semiconductor layers, the undivided region is a region where different types of reaction gases coexist. In this case, an undesired semiconductor layer grows on the substrate, even if only temporarily.

If this undesired semiconductor layer is formed at a heterojunction interface or an impurity doping modulation interface, the steepness of the heterojunction interface or doping modulation interface is lost, resulting in deterioration of the characteristics of the semiconductor device.

Furthermore, in the above-mentioned vapor phase growth apparatus for forming a plurality of different semiconductor layers, operations such as inserting and pulling out the substrate using a substrate holder, and inserting it into a separate growth chamber are essential, which makes handling of the apparatus cumbersome.

These problems can be solved by the fact that in conventional vapor phase growth equipment for producing multiple different semiconductor layers, the partition wall that divides the inside of the reaction tube into multiple growth chambers extends long in the longitudinal direction of the reaction tube. This is due to the fact that when moving the substrate holder from one growth chamber to another, it must pass through the end of this long partition wall.

The problem to be solved by the present invention is that when a substrate holder is moved from one growth chamber to another, it does not pass through the end of the partition wall that divides the interior of the reaction tube into a plurality of reaction chambers. The goal is to make it happen.

(d) Means for Solving the Problems In order to solve the above problems, the present invention provides a reaction tube, a partition wall that extends inside the reaction tube and divides the inside of the reaction tube into a plurality of reaction chambers, and a plurality of different A plurality of different semiconductors having a substrate on which a semiconductor layer is grown in a vapor phase, a gas pipe that supplies different types of reaction gas to the plurality of growth chambers, and a gas intake pipe that takes in the reaction gas in the reaction tube. In the layer vapor phase growth apparatus, (a) is provided continuously to the partition wall and extends into the divided reaction tube like the partition wall to divide the inside of the reaction tube into a plurality of reaction chambers; a fixed susceptor that is provided with a window that communicates with the growth chambers and that generates heat upon application of high-frequency power; (b) a fixed susceptor that is provided with a recessed portion for holding a substrate and that is slidably movable between the plurality of growth chambers via the window; a movable susceptor that generates heat upon application of high-frequency power; (c) formed integrally with the fixed susceptor, extending across the plurality of growth chambers to support the movable susceptor; and (d) a high-frequency coil for high-frequency heating the fixed susceptor, the movable susceptor, and the support.

(e) Effect In the present invention, since the above measures are taken, the movable susceptor holding the substrate (which also functions as a substrate holder) communicates between the plurality of growth chambers provided in the fixed susceptor which also functions as a partition wall. It can be slid so that it can be fed directly to the growth position in each growth chamber through the window. Therefore, when moving a substrate from one growth chamber to another using a substrate holder (movable susceptor), the partition wall (fixed susceptor) that divides the reaction tube into multiple growth chambers must be removed. No need to pass through the edge.

(f) Embodiments of the Invention Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 6.

First Example In this example, the present invention is applied to a vapor phase growth apparatus for forming a plurality of different semiconductor layers, which comprises a vertical reaction tube.

Each part of the vapor phase growth apparatus in FIG. 1 for explaining this embodiment is as follows.

1 is a reaction tube made of quartz, and 2 is a liner tube 3 made of quartz that is arranged coaxially with the reaction tube 1 and defines the inside of the reaction tube.
is a partition wall made of quartz that is located in the center of the liner tube 2 and divides the inside of the liner tube 2.

The partition wall 3 has the role of dividing the interior of the reaction tube 1 defined by the liner tube 2 into two growth chambers.

Further, 4 is a fixed susceptor made of carbon, which is provided continuously with and below the partition wall 3, and divides the inside of the liner tube 2 into two growth chambers like the partition wall 3;
5 is a window spanning two growth chambers opened in the fixed susceptor 4; 6 is a substrate on which a plurality of different semiconductor layers are to be grown in vapor phase; and 7 is a concave portion for accommodating the substrate 6; A movable susceptor made of carbon whose height does not exceed the surface of the movable susceptor, 8 a rotating shaft made of quartz that is connected to the movable susceptor 7 and rotates it, 9 integrally formed with the fixed susceptor 4, A movable susceptor 7 straddles the two divided growth chambers.
This is the support part that supports the.

The fixed susceptor 4, the movable susceptor 7 in which the substrate 6 is housed, the support portion 9, etc. are made of carbon, and generate heat when high frequency power is applied from a high frequency coil (not shown). Since carbon materials are easy to process, partition wall structures and the like can be created precisely, and gas leakage from the two divided growth spaces can be minimized. Furthermore, since the sliding lubricity between the movable susceptor 7 and the support portion 9 is good, it is easy to repeatedly move the substrate 6 between the two growth chambers.

Further, 10 and 11 are gas pipes that flow different source gases into the two chambers divided by the partition wall 3, and 13
1 is a stainless steel manifold, 14 is a gas intake pipe, and 15 is a movable susceptor 7 connected to the rotating shaft 8.
16 is a fastening ring that fastens the manifold 13 to the reaction tube 1.

The manifold 13 sends the gas inside the growth chamber, which is divided into two chambers, to the gas intake pipe 14, and by loosening the upper and lower fastening rings 16 of the manifold 13, the liner tube 2 inside the reaction tube 1 can be pulled out downward. At the same time, the substrate 6 can be taken out by pulling out the susceptor assembly including the fixed susceptor 4, the movable susceptor 7, and the support part 9 from the liner tube 2 along the tube axis of the reaction tube.

FIG. 2 is a side view showing the configuration of main parts of the susceptor assembly such as the fixed susceptor 4, movable susceptor 7, and support part 9 in FIG. 1, and FIG. 3 is a top view thereof. In the figure, the same parts as in FIG. 1 are given the same reference numbers.

Reference numeral 17 denotes a recess provided in the movable susceptor 7 to accommodate the substrate 6.

The movable susceptor 7 is driven by a rotating shaft 8 controlled by the substrate movement control section 15, and can slide between the left and right growth chambers through a window 5 provided in the fixed susceptor 4.

Next, an FET buffer layer made of non-doped GaAs and an n-
An example in which a FET active layer made of GaAs is continuously grown will be explained.

First, on one side of the growth chamber, which is divided into two,
Raw material gas for forming the FET buffer layer is introduced through the gas pipe 10.

The raw material gases introduced into the gas pipe 10 are for growing non-doped GaAs, and include hydrogen, arsine (AsH ₃ ), trimethylgallium TMG
It consists of [GaCH ₃ ) ₃ ].

In addition, on the other side of the growth chamber divided into two rooms,
Raw material gas for forming the FET operating layer is introduced through the gas pipe 11.

The raw material gas introduced into the gas pipe 11 is n-
It grows GaAs, hydrogen, arsine,
Trimethylgallium TMG, hydrogen sulfide (H ₂ S)
It is made up of

In the reaction tube 1, a fixed susceptor 4 that divides the inside of the growth chamber 1 defined by the liner tube 2 into two chambers, a movable susceptor 7 that accommodates a substrate 6 made of GaAs, and a support section 9 are equipped with a high-frequency wave (not shown). It is heated to approximately 700°C by a coil.

In this state, time is controlled to first grow non-doped GaAs which will become the FET buffer layer in the growth chamber on one side, and then the substrate movement control section 15
The rotary shaft 8 is rotated, the movable susceptor 7 is rotated by half a rotation, the substrate 6 is moved to the growth chamber on the other side, and n-GaAs, which will become the FET operating layer, is grown.

Second Embodiment FIG. 4 is a perspective view for explaining a second embodiment of the present invention applied to a horizontal reaction tube.

In the figure, the same functional parts as in FIG. 1 are given the same reference numbers. However, reaction tube 1 in Figure 1
is not shown.

In this embodiment, as shown in FIG. 4, the inside of the liner tube 2 is divided by a partition wall 3 made of quartz and a fixed susceptor 4 made of carbon connected to the partition wall 3 to form two growth chambers. has been done.

Furthermore, the fixed susceptor 4 is provided with a window 5 that communicates between the two growth chambers, and a support part 9 that is integrally formed with the fixed susceptor 4, and a substrate 6 is stored on the surface of the support part 9. A movable susceptor 7 is rotatably arranged.

The main difference from the structure of the vertical reaction tube in Figure 1 is:
The driving portion of the movable susceptor 7, that is, the rotating shaft 8 is driven by a horizontal driving shaft 19 via a gear 18 made of carbon.

In this embodiment, as in the first embodiment, the movable susceptor 7 can slide between the two growth chambers through the window 5 provided in the fixed susceptor 4.

Third Embodiment In the first and second embodiments described above, the substrate was moved between the reaction chambers by sliding movement due to the rotation of the movable susceptor, but instead of this, sliding movement in a horizontal plane is adopted. You can also do that.

FIG. 5 is a sectional view of a main part of a vapor phase growth apparatus for a plurality of different semiconductor layers in which a substrate is slid in a horizontal plane, and FIG. 6 is a perspective view of FIG. 5.

In FIGS. 5 and 6, the basic structures such as the partition wall 3 forming the two growth chambers, the fixed susceptor 4, and the support part 9 formed integrally with the fixed susceptor 4 are the same as in FIG. 1. be.

In the figure, 20 is a movable susceptor that slides in the left-right direction within the window 5 of the fixed susceptor 4, and is provided with a recessed portion in which the substrate 6 is accommodated. Reference numeral 21 indicates a rail serving as a slide guide provided on the upper surface of the support portion 9, 22 a rack gear provided on one side of the bottom surface of the movable susceptor 20, and 23 a pinion gear meshing with the rack gear 22.

The pinion gear 23 is driven by a substrate movement control section (not shown) (see FIG. 1) via a rotating shaft 8 at the center of the liner tube 2. By changing the positive and negative rotation directions of the rotating shaft 8, the movable susceptor 7 can slide between the two growth chambers through the window 5 provided in the fixed susceptor 4.

(g) Effects of the Invention According to the present invention, the fixed susceptor and the supporting part formed integrally with the fixed susceptor generate heat together with the movable susceptor by applying power from the high-frequency coil, so that the amount of heat generated by the movable susceptor is reduced. Even if the movable susceptor changes its position relative to the high-frequency coil due to its movement, the amount of heat generated by it may vary), the total amount of heat generated to heat the substrate remains almost unchanged, and therefore,
The heating temperature of the substrate is always maintained substantially constant, resulting in the effect that undesired growth of the semiconductor layer due to temperature fluctuations can be prevented.

[Brief explanation of the drawing]

Figure 1 shows a first example in which the present invention is applied to a vertical reaction tube.
FIG. 2 is a side view showing the main structure of FIG. 1, FIG. 3 is a top view of FIG. 2, and FIG. 4 is a simplified perspective view for explaining the embodiment. A simplified perspective view for explaining the second embodiment, No. 5
This figure is a sectional view for explaining a third embodiment in which a movable susceptor is moved by a slide mechanism, and FIG. 6 is a perspective view of FIG. 5. In the figure, 1 is a reaction tube, 2 is a liner tube, 3 is a partition wall, 4 is a fixed susceptor, 5 is a window, 6 is a substrate, 7 is a movable susceptor, 8 is a rotating shaft, 9 is a support part, 10 and 11 are 13 is a manifold, 14 is a gas intake pipe, 15 is a substrate movement control unit, 16 is a fastening ring, 17 is a recessed part, 18 is a gear, 19 is a horizontal drive shaft, 20 is a sliding movable susceptor, 21
is a rail, 22 is a rack gear, and 23 is a pinion gear.

Claims (1)

[Scope of Claims] 1. A reaction tube, a partition wall extending from the upstream side of the reaction gas and dividing the interior of the reaction tube into a plurality of growth chambers, and supplying different types of reaction gases to the plurality of growth chambers. a gas pipe; a gas intake pipe that takes in the reaction gas in the reaction tube; and a gas intake pipe that is provided continuously to the partition wall and extends into the divided reaction tubes similarly to the partition wall to carry out a plurality of reactions in the reaction tubes. A fixed susceptor that is divided into chambers and provided with a window that communicates the plurality of growth chambers and that generates heat when high frequency power is applied, and holds a substrate on which a plurality of different semiconductor layers are grown in a vapor phase. a movable susceptor that generates heat upon application of high-frequency power and is provided with a recessed portion and is slidably movable between the plurality of growth chambers via the window; The present invention further comprises: a support portion extending over the growth chamber to support the movable susceptor and generating heat upon application of high-frequency power; and a high-frequency coil for high-frequency heating the fixed susceptor, the movable susceptor, and the support portion. A vapor phase growth apparatus for producing multiple different semiconductor layers.