JP3331052B2 - Semiconductor device and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION This invention relates to a semiconductor device and a manufacturing method thereof, such as a solar cell using a semiconductor film.

[0002]

2. Description of the Related Art A conventional method for manufacturing a semiconductor device using a semiconductor film will be described with reference to FIGS. 13 and 14 show, for example, U.S. Pat.
FIG. 7 is a schematic view showing a conventional method for manufacturing a semiconductor device disclosed in Japanese Patent No. 7,047 and US Pat. No. 4,816,420.

In FIGS. 13 and 14, reference numeral 100 denotes a substrate, 101 denotes an insulating film covering the substrate 100, and 1 denotes a semiconductor film.

The substrate 100 and the semiconductor film 1 are made of gallium arsenide. First, the surface of the substrate 100 shown in FIG. Next, as shown in FIG. 13B, openings are provided in a stripe shape in the insulating film 101 to expose the surface of the substrate 100. Next, FIG.
(C) As shown in FIGS. 14A and 14B, the semiconductor film 1 is crystal-grown using the exposed substrate surface as a nucleus.

[0005] In the structure shown in FIG. 14 (b), the semiconductor film 1 is provided only on the opening of the insulating film 101.
Is connected to the semiconductor film 1.
And the semiconductor film 1 has a weak bond with the semiconductor film 1.
By applying a mechanical stress to the substrate 100, the connection portion with the substrate 100 is broken and the semiconductor film 1 can be peeled off from the substrate 100, as shown in FIG.

However, in this method, since the connection with the substrate 100 is broken and the semiconductor film 1 is forcibly peeled off, the separation cannot always be performed without damaging the semiconductor film 1 itself. However, there was a problem that the yield was poor.

Next, a conventional semiconductor device manufacturing apparatus will be described with reference to FIG. FIG. 15 is a perspective view showing a conventional semiconductor device manufacturing apparatus.

In FIG. 15, reference numeral 600 denotes a semiconductor wafer;
Reference numeral 500 denotes an apparatus, and reference numeral 501 denotes a groove into which the semiconductor wafer 600 is inserted. This apparatus 500 is configured to insert one semiconductor wafer 600 into each groove 501 and handle a total of 25 semiconductor wafers 600 simultaneously. Then, while the semiconductor wafer 600 is loaded, wet processing such as cleaning and etching and transport are performed.

However, when a semiconductor device is manufactured by processing the semiconductor wafer 600 as used in a conventional semiconductor device, the semiconductor wafer 600 has a large mechanical strength, and therefore, as shown in FIG. Such device 50
0, it can be handled only by holding the peripheral portion thereof. However, when handling a semiconductor film having a thickness of 100 μm or less, the mechanical strength of the semiconductor film is weak. In the case of 500, there is a problem that the semiconductor film is easily broken and the yield is poor.

Next, a method for loading the semiconductor wafer 600 into the apparatus 500 will be described with reference to FIG.
FIG. 16 is a diagram showing a state where a semiconductor wafer is loaded in a conventional semiconductor device manufacturing apparatus.

In FIG. 16, reference numeral 502 denotes a semiconductor wafer 6.
Is a belt for transporting the semiconductor wafer 60
0 is transported on the belt 502 and the device 500
In the groove 501.
A stage 503 moves the device 500 up and down.

However, the handling of the semiconductor wafer 600 is based on the premise that the semiconductor wafer 600 has sufficient mechanical strength. Therefore, also in this case, when a semiconductor film having a thickness of 100 μm or less is handled, the mechanical strength of the semiconductor film is weak, and therefore, in the device 500, the semiconductor film is easily broken and the yield is low. was there.

Further, another conventional method of manufacturing a semiconductor device using a semiconductor film will be described with reference to FIGS. FIG. 17 shows a semiconductor device using a semiconductor film having a structure in which a diffusion layer is provided on the surface of the semiconductor film, the inner wall of the through hole extending from the front surface to the back surface, and at least the periphery of the through hole on the back surface of the semiconductor film. It is a figure showing the conventional manufacturing method.

17A to 17C, reference numeral 1 denotes a semiconductor film, 2 denotes a through hole provided in the semiconductor film 1, 3 denotes a diffusion layer provided in the semiconductor film 1, and 5 denotes a resist.

FIG. 17A shows a state in which a diffusion layer 3 is provided on the front surface of the semiconductor film 1, the inner wall of the through hole 2, and the back surface of the semiconductor film 1. Thereafter, as shown in FIG. 17B, a resist 5 is applied to the front surface of the semiconductor film 1, the inner wall of the through hole 2, and the peripheral portion of the through hole 2 on the back surface of the semiconductor film 1 by photolithography or screen printing. Is formed. next,
As shown in FIG. 17C, the semiconductor film 1 is immersed in an etchant to etch the diffusion layer 3 in a region other than the peripheral portion of the through hole 2 on the back surface of the semiconductor film 1. After that, the resist 5 is removed, and an electrode is provided on the back surface of the semiconductor film 1 as shown in FIG.

However, in this method, it is necessary to form the resist 5 on both sides of the semiconductor film 1, so that
There is a problem that handling of the semiconductor film 1 in a state where the resist 5 is formed becomes difficult and productivity is extremely low. Further, since the semiconductor film 1 itself needs to be etched, there is a disadvantage that only the surface damaged by the etching can be obtained on the surface from which the diffusion layer 3 is removed. Incidentally, when dry etching is used, the formation of the resist 5 may be performed only on the back surface, but there is a problem that the etching damage is further increased.

FIG. 18 is a view showing a conventional semiconductor device having a structure in which a diffusion layer is provided on the front surface of a semiconductor film, the inner wall of a through hole extending from the front surface to the back surface, and at least the periphery of the through hole on the back surface of the semiconductor film. It is. 2A is a view from the back, FIG. 2B is a cross-sectional view along the line AA ′ shown in FIG. 2A, and FIG. 2C is a view from the line BB ′ shown in FIG. Each of the cross-sectional views is shown.

Since the electrodes 4A and 4B connected to the diffusion layer 3 are provided on the back surface of the semiconductor film 1, the diffusion layer 3 is formed on the back surface according to the pattern of the electrodes 4A and 4B as well as the peripheral portion of the through hole 2. Have been. For this reason, the area of the region of the diffusion layer 3 is increased, which hinders the improvement of the performance as a semiconductor device.

In the semiconductor film 1, through holes 2 are formed at regular intervals. The current-voltage characteristics representing the performance of the semiconductor device largely depend on the resistance of the surface of the semiconductor film 1 in the through-hole 2 and the interval between the through-holes 2. If these parameters are not properly controlled, sufficient characteristics are obtained. It was difficult to obtain the semiconductor device of the above.

[0020]

The above-described conventional method for manufacturing a semiconductor device using a semiconductor film and the above-described apparatus for manufacturing a semiconductor device are configured as described above, so that the yield is low and the productivity is low. There was a problem that was bad. In addition, since the conventional semiconductor device using the semiconductor film is configured as described above, there is a problem that it is difficult to obtain a device having sufficient performance.

[0021] The present invention has been made to solve the above problems, capable of handling semi conductor film easily manufacturing a semiconductor device which can be improved yield and improve productivity The aim is to get the method .
Another object is to obtain a semiconductor device having excellent characteristics.

[0022]

According to a first aspect of the present invention, there is provided a semiconductor device, comprising: a semiconductor film having a front surface, an inner wall of a through hole extending from the front surface to the back surface, and a periphery of the through hole on the back surface of the semiconductor film; A semiconductor device having a structure in which both the electrode connected to the diffusion layer and the electrode of the other electrode are provided on the back surface side of the semiconductor film. Except for the contact portion to the diffusion layer and the contact portion of the other pole electrode to the semiconductor film, the semiconductor film is covered with an antireflection film made of a silicon nitride film, and the thickness of the semiconductor film is 100 μm or less. And before
The electric resistance between the front and back of the semiconductor film in the through hole per one
It is a 10Ω or less, the through hole is one that are arranged at a pitch less than 1.5 mm.

According to a second aspect of the present invention, a semiconductor device is manufactured.
The fabrication method reaches the front surface of the semiconductor film, from this surface to the back surface
Around the inner wall of the through hole and the through hole on the back surface of the semiconductor film
A method of manufacturing a semiconductor device including a step of providing a diffusion layer in a semiconductor device.
The front surface, the rear surface, and the inner wall of the through hole.
After forming an anti-reflection film made of a con-nitride film, the diffusion
Remove the anti-reflective coating in the area other than the area where the layer is to be provided.
Exposing the semiconductor film and using the remaining anti-reflection film as a mask
And etching the semiconductor film to thereby expand the semiconductor film.
This is to form a pattern of a dispersed layer .

According to a third aspect of the present invention, there is provided a semiconductor device .
The fabrication method reaches the front surface of the semiconductor film, from this surface to the back surface
Around the inner wall of the through hole and the through hole on the back surface of the semiconductor film
A method of manufacturing a semiconductor device including a step of providing a diffusion layer in a semiconductor device.
And the inner surface of the front surface, the rear surface, and the through hole has C
1000 Å thick straw deposited by VD method
After forming an insulating film consisting of a silicon oxide film
Removing the insulating film according to the formation pattern of the diffusion layer;
And the diffusion layer is exposed by impurity diffusion.
Was formed, the diffusion layer was formed, and the remaining insulating film was removed.
After that, the front surface, the back surface and the inner wall of the through hole are made of silicon.
An anti-reflection film made of a nitride film is formed and is in contact with the diffusion layer.
The contact between the electrode and the diffusion layer
The antireflection film at the contact portion of the pole to the semiconductor film was removed
After that, the electrodes connected to the diffusion layer and the other electrode
It forms the poles .

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[0044]

In the semiconductor device according to the first aspect of the present invention, a diffusion layer is provided on the surface of the semiconductor film, the inner wall of the through hole extending from the surface to the back surface, and the periphery of the through hole on the back surface of the semiconductor film. A semiconductor device having a structure in which both an electrode connected to the diffusion layer and an electrode of the other electrode are provided on the back surface side of the semiconductor film, wherein an electrode connected to the diffusion layer contacts the diffusion layer. Except for the contact portion of the electrode of the other part and the electrode of the other pole to the semiconductor film, since the semiconductor film is covered with an insulating film, the area of the diffusion layer is reduced,
The performance of the semiconductor device is improved. Further, since the insulating film is used as an anti-reflection film of a semiconductor device, the number of steps is reduced in the case of manufacturing a solar cell, and productivity and yield are improved.
Further, the thickness of the semiconductor film is 100 μm or less,
One electric resistance between the front and back of the semiconductor film in the through hole hits
10Ω or less and the through holes are arranged at a pitch of 1.5 mm or less, so that sufficiently excellent performance as a solar cell can be obtained.

The manufacturing of the semiconductor device according to claim 2 of the present invention .
In the fabrication method , the surface of the semiconductor film, from this surface to the back surface
Through the inner wall of the through hole that reaches
Manufacturing of a semiconductor device including a step of providing a diffusion layer around a hole
The method, wherein the front surface, the back surface, and the through hole
After the insulating film is formed on the wall, the area where the diffusion layer is to be provided
The semiconductor film is exposed by removing the insulating film in a region other than the above.
And etching the semiconductor film using the remaining insulating film as a mask.
To form a pattern of the diffusion layer
Therefore, the resist only needs to be formed on the back side of the semiconductor film.
In addition, productivity and yield can be greatly improved. In addition,
Since the insulating film was used as an anti-reflection film for semiconductor devices,
Ponds reduce the number of steps and can improve productivity and yield.

The manufacturing of the semiconductor device according to claim 3 of the present invention .
In the fabrication method , the surface of the semiconductor film, from this surface to the back surface
Through the inner wall of the through hole that reaches
Manufacturing of a semiconductor device including a step of providing a diffusion layer around a hole
The method, wherein the front surface, the back surface, and the through hole
After forming the insulating film on the wall, the pattern of the diffusion layer
Therefore, the insulating film is removed to expose the semiconductor film, and
Since the diffusion layer is formed by pure substance diffusion, the diffusion layer
Need to etch semiconductor film itself for turning
No penetration through the back without damaging the front
The diffusion layer can be formed only on the periphery of the hole opening. In addition, the extension
After forming a diffused layer and removing the remaining insulating film,
Another insulating layer is formed on the back surface and the inner wall of the through hole, and
The contact between the electrode connected to the diffusion layer and the diffusion layer
The another insulating film at a contact portion of one electrode of the electrode with the semiconductor film;
Is removed, the electrode connected to the diffusion layer and another
The process further includes the step of forming the electrode of
High performance equipment can be manufactured, improving productivity and yield
You. Further, the insulating film is deposited by a CVD method.
Etching is easy because of the silicon oxide film
This is convenient in terms of consistency with other processes. Again
Further, the thickness of the silicon oxide film is set to 1000 Å.
Light before the impurity diffusion
Not etched by etching .

[0047]

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[0065]

【Example】

Embodiment 1 FIG. A method for manufacturing a semiconductor device according to one embodiment of the present invention will be described with reference to FIG. FIG. 1 (a)
FIGS. 1C to 1C are schematic views for explaining a method of manufacturing a semiconductor device according to one embodiment of the present invention.

1A to 1C, reference numeral 100 denotes a substrate, 10 denotes a release layer, 11 denotes water, 1 denotes a semiconductor film, and 2 denotes a through hole formed in the semiconductor film 1.

For example, the substrate 100 is made of a single crystal silicon wafer, and the release layer 10 is made of a silicon oxide film formed by thermally oxidizing the substrate 100. Alternatively, the release layer 10
May be a silicon oxide film deposited by a method such as CVD. The thickness of the single crystal silicon wafer is usually 625 μm when the diameter is 6 inches. The thickness of the release layer 10 is, for example, 1 μm. The semiconductor film 1 has C on the release layer 10.
It is a polycrystalline silicon film deposited by a method such as VD. Further, the electrical characteristics may be improved by enlarging the crystal grain size by means such as zone melting recrystallization or solid phase growth. The thickness of the semiconductor film 1 is desirably about 30 to 50 μm when, for example, a solar cell is formed using the semiconductor film 1.

FIG. 1A shows that a release layer 10 is formed on the semiconductor film 1.
3 shows a state in which a through hole 2 is provided. In this state, it is immersed in hydrofluoric acid (not shown),
Hydrofluoric acid is introduced from the through hole 2 to remove the peeling layer 10 by etching, and then washed with water, and the space between the semiconductor film 1 and the substrate 100 is replaced with water 11 as shown in FIG. In this state, the water 11 functions as an adhesive between the semiconductor film 1 and the substrate 100, and the semiconductor film 1 cannot be easily peeled off from the substrate 100. By the way, even if the semiconductor film 1 is left in this state or is heated and dried to eliminate the water 11 between the semiconductor film 1 and the substrate 100, a bond is formed between the two, and the semiconductor film 1 is spontaneously formed. No peeling occurs.

Therefore, when the substrate 100 is held in the state shown in FIG. 1B and a lateral force is applied to the semiconductor film 1 along the surface of the substrate 100 as shown by an arrow in the figure,
The water 11 between the semiconductor film 1 and the substrate 100 serves as a lubricant, and the semiconductor film 1 can easily slide on the substrate 100. In this way, as shown in FIG.
The semiconductor film 1 is pulled out from above the substrate 100 and the substrate 100
It is separated from. By this method, the semiconductor film 1
When was made of silicon, it was possible to easily separate a product having a thickness of 10 μm and a size of 10 cm square.

In the first embodiment, when the semiconductor film 1 is separated, the space between the semiconductor film 1 and the substrate 100 is filled with water 11 or an aqueous solution, and the semiconductor film 1 is slid along the substrate surface to be separated. Things. Therefore, the semiconductor film 1 can be separated without damaging it, the yield can be improved, and the productivity can be improved.

Embodiment 2 FIG. Second Embodiment A semiconductor device manufacturing apparatus according to a second embodiment of the present invention will be described with reference to FIG. FIG. 2 is a schematic sectional view showing an apparatus for realizing the method of manufacturing the semiconductor device shown in FIG.

In FIG. 2, reference numeral 21 denotes a first area, 22 denotes a second area, 23 denotes a step between the first area 21 and the second area 22, and 24 denotes a frame.

A flat plate made of tetrafluoroethylene resin (registered trademark “Teflon”) having a thickness of about 1 cm is spotted, and flat first and second regions 21 and 22 are formed as shown in FIG. To form The first region 21 is formed by counterbore uniformly at a depth of about two to three times the thickness of the substrate 100, and the second region 22 is formed by slightly counterbore.
The first region 21 and the second region 22 are formed in areas where the substrate 100 and the semiconductor film 1 can be accommodated, respectively. First
The step 23 between the region 21 and the second region 22 is set to be smaller than the thickness of the substrate 100 and larger than half the thickness of the substrate 100. The frame 2 is left around the first area 21 and the second area 22 except for a portion without spot facing.
4 is assumed.

Next, a method of manufacturing a semiconductor device using the device shown in FIG. 2 will be described. In a state where the semiconductor film 1 as shown in FIG.
Put 0 in the first area. In this state, the whole is immersed in water or wetted with water, and a force is applied to the semiconductor film 1 in the lateral direction to move the semiconductor film 1 to the second region 22. At this time, the substrate 100 is caught by the step 23 and cannot move to the second region 22. However, since the step 23 is set smaller than the thickness of the substrate 100, the semiconductor film 1 on the substrate 100
Can move smoothly without being hindered by the step 23. The semiconductor film 1 is completely in the second region 2
2, the separation of the semiconductor film 1 and the substrate 100 is completed. Therefore, the semiconductor film 1 can be separated without damaging it, the yield can be improved, and the productivity can be improved.

At this time, the lateral force applied to the semiconductor film 1 is:
For example, the end may be added by pressing the end of the semiconductor film 1 with a jig, or the surface of the semiconductor film 1 may be entirely pressed with a soft material and applied by friction. Alternatively, the semiconductor film 1 may be moved by gravity while tilting the whole. At this time, when vibration such as ultrasonic wave is applied, the movement of the semiconductor film 1 becomes smoother. Further, the semiconductor film 1 may be moved by a frictional force with water by applying a water flow from above the semiconductor film 1 toward the second region 22.

In the second embodiment, the step 23 is
The reason why the thickness is set to be larger than half of the thickness of 00 is as follows. That is, the periphery of the substrate 100 is usually chamfered, and the cross section thereof has a slightly rounded shape. Therefore, if the step 23 is smaller than half the thickness of the substrate 100, the substrate 100 rides on the step 23 when a force for moving the semiconductor film 1 to the second region 22 is applied. The second area 22
The semiconductor film 1 and the substrate 10
This is because it is possible that separation from zero cannot be achieved.

Embodiment 3 FIG. Third Embodiment A semiconductor device manufacturing apparatus according to a third embodiment of the present invention will be described with reference to FIG. Third Embodiment FIG. 3 is a schematic sectional view illustrating a semiconductor device manufacturing apparatus according to a third embodiment of the present invention.

In FIG. 3, reference numeral 31 denotes a first space, and 32 denotes a second space.

A first space 31 and a second space 32 are formed by combining a plate material of tetrafluoroethylene resin and the like.
The first space 31 is large enough to accommodate the semiconductor film 1 attached to the substrate 100, and the second space 32 is
Each is configured to have a size that accommodates only one.
The thickness of each space is such that the first space 31
The second space 32 is smaller than the thickness of the substrate 100 and larger than the thickness of the semiconductor film 1.

In this state, if the release layer 10 is etched and removed by immersion in hydrofluoric acid, the force for fixing the semiconductor film 1 to the substrate 100 is lost. To move toward the second space 32. Since the size of the substrate 100 cannot move to the second space 32, only the semiconductor film 1 moves to the second space 32, and the semiconductor film 1 and the substrate 100 are separated. Therefore, the semiconductor film 1 can be separated without damaging it, the yield can be improved, and the productivity can be improved.

Embodiment 4 FIG. Fourth Embodiment A semiconductor device manufacturing apparatus according to a fourth embodiment of the present invention will be described with reference to FIG. FIG. 4 is a schematic front view showing a semiconductor device manufacturing apparatus according to Embodiment 4 of the present invention.

In FIG. 4, 31A is a first space, 32A
A is a second space.

In the third embodiment, the first space 3
Although the thickness of the first and second spaces 32 was changed, in the fourth embodiment, as shown in FIG. 4, a case where the semiconductor film 1 is smaller than the size of the substrate 100 by combining a plate material of tetrafluoroethylene resin or the like. In this configuration, the width of the second space 32A is smaller than the width of the first space 31A so that the semiconductor film 1 enters but the substrate 100 does not enter.

Similarly, in this case, if the release layer 10 is etched and removed by immersion in hydrofluoric acid, the force for fixing the semiconductor film 1 to the substrate 100 is lost. It moves along the surface of 100 toward the second space 32A. The substrate 100 is in the second space 3
2A, only the semiconductor film 1 moves to the second space 32A, and the semiconductor film 1 and the substrate 10
The separation from zero is performed. Therefore, the semiconductor film 1 can be separated without damaging it, the yield can be improved, and the productivity can be improved.

Embodiment 5 FIG. A method for manufacturing a semiconductor device according to Embodiment 5 of the present invention will be described.

In FIG. 1 showing the first embodiment, hydrofluoric acid is introduced from the through hole 2 provided in the semiconductor film 1 and reaches the release layer 10, and the release layer 10 is removed by etching. The step of removing the connection between the substrate 1 and the substrate 100 has been described. At this time, it is generally known that the etching rate of the silicon oxide film with hydrofluoric acid depends on the temperature of hydrofluoric acid.

Since a narrow gap between the semiconductor film 1 and the substrate 100 must be etched through the narrow hole of the through hole 2, it takes a very long time at room temperature to complete the etching. When the distance between the through holes 2 was 1 mm, it took about one day and night. The required time did not change significantly even when the size of the through hole 2 or the thickness of the release layer 10 was changed.

On the other hand, by increasing the temperature of hydrofluoric acid, the time required for completing the etching was greatly reduced. It has been found that raising the temperature to 50 ° C. or higher is effective. Thereby, when the interval between the through holes 2 was 1 mm, the etching was completed in 2 to 3 hours. Therefore, the semiconductor film 1 can be separated without damaging it, the yield can be improved, and the productivity can be improved.

The reason why it is effective to raise the temperature to 50 ° C. or higher is considered as follows. That is, for one thing, the reaction becomes active and the etching speed itself increases. Second, the gas components generated by the etching are easily vaporized and become bubbles to form the semiconductor film 1.
To increase the gap between the semiconductor film 1 and the substrate 100 to improve the flow of hydrofluoric acid. This effect is more remarkable as the thickness of the semiconductor film 1 is smaller. Thirdly, the viscosity of hydrofluoric acid is reduced, so that the hydrofluoric acid is more likely to enter the gap between the semiconductor film 1 and the substrate 100.

Embodiment 6 FIG. Sixth Embodiment A semiconductor device manufacturing apparatus according to a sixth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a schematic sectional view showing an apparatus for realizing the method of manufacturing a semiconductor device according to the fifth embodiment.

In FIG. 5, reference numeral 51 denotes a first container filled with hydrofluoric acid 33, 52 denotes a second container filled with water 11, and 53 denotes a heating unit provided at the bottom of the second container 52. The device 54 is a temperature control device which is connected to the heating device 53 and a temperature sensor (not shown) provided in the water and comprises a CPU, a ROM, a RAM and the like. 510 is the first
The lid 520 of the container 51 is a lid of the second container 52.

The first container 51 and the second container are made of tetrafluoroethylene resin. These are seamlessly molded single-piece products made by cutting from a tetrafluoroethylene resin block. In the first container 51, the above Examples 2 to
The device of No. 4 is put in and the required amount of hydrofluoric acid 33 is filled. The first container 51 is placed in the second container 52, and the gap is filled with a required amount of water 11. The first container 51 has a lid 51.
The 0 and 2nd containers have a lid 520, which can be hermetically sealed. The peripheral portion of the lid 510 is formed so as to cover the first container 51 body from outside. This is because when the water evaporated by heating falls as water droplets on the inner surface of the lid 510, the moisture is mixed into the first container 51 from the gap of the lid 510 and lowers the concentration of hydrofluoric acid 33 therein. This is to prevent that.

In this state, the water 11 in the container is heated by the heating device 53 in the second container 52, and the temperature is controlled by the temperature control device 54 to a constant value of 50 ° C. or more. Thereby, the first container 51 is heated, and the hydrofluoric acid 33 in the first container 51 is heated indirectly. With this configuration, the strongest acid, hydrofluoric acid 33, can be prevented from directly contacting the heating device 53, and stable heating can be performed. In addition, the amount of hydrofluoric acid 33 can be minimized. It is possible to save the usage amount and use it effectively.

Embodiment 7 FIG. Seventh Embodiment A semiconductor device manufacturing apparatus according to a seventh embodiment of the present invention will be described with reference to FIG. FIG. 6 is a schematic view showing an apparatus for manufacturing a semiconductor device according to the present invention.

In FIG. 6, reference numeral 61 denotes a mesh made of tetrafluoroethylene resin. 1 is a semiconductor film.

The semiconductor film 1 is held in a gap surrounded by two meshes 61 made of tetrafluoroethylene resin. In this state, wet processing such as cleaning and etching is performed. The mesh pitch of the tetrafluoroethylene resin mesh 61 is 0.5 mm or more and 2.5 mm or less. The reason why the mesh pitch is 0.5 mm or more is that if the mesh pitch is smaller than this, water or an etching solution may not penetrate due to surface tension.

However, if the mesh pitch is too large, the stress applied to the semiconductor film 1 during processing will increase. A case where a 6-inch (150 mm) wafer is supported only by its peripheral portion as in a conventional manufacturing apparatus (FIG. 1)
5), the thickness of a 6-inch wafer is 0.6
Since it is 25 mm, the aspect ratio is 250. Considering the same aspect ratio for the semiconductor film 1 having a thickness of 100 μm, the mesh pitch is 25 mm. Considering the case where the safety factor is 10 times and the thickness of the semiconductor film 1 is 10 μm, the mesh pitch is 2.5 mm.

Embodiment 8 FIG. Embodiment 8 A method for manufacturing a semiconductor device according to Embodiment 8 of the present invention will be described with reference to FIG. FIG. 7 is a schematic view illustrating a method for manufacturing a semiconductor device according to Embodiment 8 of the present invention.

In FIG. 7, reference numeral 71 denotes water (water flow).
1 is a semiconductor film, and 2 is a through hole.

The semiconductor film 1 is formed by the surface tension of the water 71.
Floating on its surface. At this time, the force supporting the semiconductor film 1 is applied to the entire contact surface between the semiconductor film 1 and the water 71,
No destruction of the semiconductor film 1 due to local stress load occurs. Therefore, the yield of the process is improved.
Further, since only the water 71 is in contact with the semiconductor film 1, there is an advantage that not only the water 71 can be easily moved to another place but also there is no impurity contamination.

Embodiment 9 FIG. Embodiment 9 A semiconductor device manufacturing apparatus according to Embodiment 9 of the present invention will be described with reference to FIG. FIG. 8 is a schematic diagram showing an apparatus for manufacturing a semiconductor device according to Embodiment 9 of the present invention.

In FIG. 8, 81 is a cassette, and 82 is a stage. 1 is a semiconductor film, 2 is a through hole, 61
Is a mesh made of tetrafluoroethylene resin, and 71 is water.

The semiconductor film 1 is supported by being floated on the water 71, and is moved and transported according to the flow of the water 71. When the semiconductor film 1 moves to the position of the cassette 81, the stage 8
2 rises and is scooped up by the tetrafluoroethylene resin mesh 61 set in the cassette 81, and the water 71
It moves into the cassette 81 from the surface. On this occasion,
The force for supporting the semiconductor film 1 is always uniformly applied to the entire surface of the semiconductor film 1, so that the semiconductor film 1 is not broken by a local load stress applied to the semiconductor film 1. Therefore, the yield is improved, and the productivity is improved.

Embodiment 10 FIG. Embodiment 10 A method for manufacturing a semiconductor device according to Embodiment 10 of the present invention will be described with reference to FIG. FIG. 9 is a schematic view illustrating a method for manufacturing a semiconductor device according to Embodiment 10 of the present invention. The steps will be described below in the order of steps according to the drawings.

As shown in FIG. 9A, a diffusion layer 3 is formed on the front and back surfaces of the semiconductor film 1 and on the inner wall of the through hole 2. An insulating film 12 made of, for example, a silicon nitride film, a silicon oxide film, or a laminate thereof is formed on the front surface, the back surface, and the inner wall of the through hole 2 of the semiconductor film 1.

As shown in FIG. 9B, a resist (not shown) is provided on the periphery of the opening on the back surface of the through hole 2, and the insulating film 12 is patterned from the back surface by dry etching. As a result, the insulating film 12 remains on the periphery of the opening on the back surface of the through hole 2 according to the resist pattern.

Thereafter, as shown in FIG. 9C, using the insulating film 12 as a mask, the diffusion layer 3 on the surface of the semiconductor film 1 is formed.
Is patterned using, for example, an alkaline solution such as sodium hydroxide or a mixed acid of hydrofluoric acid and nitric acid.

According to this method, the resist is applied to the semiconductor film 1
It is only necessary to form it on the back side of the substrate, and the productivity and yield are greatly improved.

This method is performed by using the semiconductor film 1
For example, when the present invention is applied to a process for manufacturing a solar cell, the use of an antireflection film formed to reduce the reflection loss of the light incident surface of the solar cell as the insulating film 12 simplifies the number of process steps and improves productivity and productivity. Yield is greatly improved. As the antireflection film, for example, a silicon nitride film can be used. Incidentally, in many cases, before providing the antireflection film, the surface of the semiconductor film 1 is passivated by thinly oxidizing the surface of the semiconductor film 1 to form a silicon oxide film. It may be said that the film is laminated.

Embodiment 11 FIG. Embodiment 11 A semiconductor device according to Embodiment 11 of the present invention will be described with reference to FIG. 10A and 10B are views showing a semiconductor device according to Embodiment 11 of the present invention, wherein FIG. 10A is a view from the back, FIG. 10B is a cross section as viewed from the line AA ′ of FIG. (A) shows a cross section taken along line BB '.

As described above, when the insulating film 12 has a function of inactivating the surface of the semiconductor film 1, as much as possible the surface of the semiconductor film 1 is covered with the insulating film 12. Is desirable in terms of performance. By the way, the diffusion layer 3
Considering a semiconductor film having a structure in which the side electrode 4A is provided on the back side of the semiconductor film 1, in a conventional semiconductor device,
As described above, the diffusion layer 3 is formed on the back surface of the semiconductor film 1 according to the electrode pattern on the diffusion layer 3 side, not only on the periphery of the opening of the through hole 2 so that the electrode 4A on the diffusion layer 3 side does not contact the other region. Needed to be formed.

On the other hand, in the embodiment shown in FIG. 10, the contact portion of the electrode 4A connected to the diffusion layer 3 with the diffusion layer 3 and the contact portion of the other electrode 4B with the semiconductor film 1 are formed. Except for this, the semiconductor film 1 is covered with the insulating film 12.
For this reason, the diffusion layer 3 needs to be formed on the back surface of the semiconductor film 1 only at the peripheral edge of the opening of the through hole 2, and the area of the region of the diffusion layer 3 can be small, and the performance of the semiconductor device is improved. further,
If an anti-reflection film for a solar cell is used as the insulating film 12 at this time, the number of steps is reduced, and the productivity and yield are improved.

Embodiment 12 FIG. A method for manufacturing a semiconductor device according to embodiment 12 of the present invention will be described with reference to FIG. FIG. 11 is a schematic sectional view showing a method for manufacturing a semiconductor device according to Embodiment 12 of the present invention. The steps will be described below in the order of steps according to the drawings.

As shown in FIG. 11A, a second insulating film 112 made of, for example, a silicon oxide film is formed on the front and back surfaces of the semiconductor film 1 and the inner wall of the through hole 2.

As shown in FIG. 11B, the second insulating film 112 is patterned according to the pattern for forming the diffusion layer 3. That is, the portion other than the region where the diffusion layer 3 is formed is covered with a resist (not shown), and the second insulating film 112 is etched.

In this state, as shown in FIG.
The diffusion layer 3 is formed by diffusing impurities such as phosphorus.

According to this method, it is not necessary to etch the semiconductor film 1 itself for patterning the diffusion layer 3, and without damaging the front surface, the through hole 2 on the back surface.
The diffusion layer 3 can be formed only on the periphery of the opening. As the second insulating film 112, a silicon oxide film formed by CVD is used; however, it is convenient in terms of easiness of formation and etching, and compatibility with other processes. In this case, light etching is usually performed with diluted hydrofluoric acid before the impurity diffusion, but at this time, the silicon oxide film is also etched at the same time. Therefore, the second insulating film 112
It is desirable that the thickness formed as above is 1000 Å or more.

In order to obtain the structure shown in FIG. 10, thereafter, an insulating film 12 is provided on the front surface, the back surface of the semiconductor film 1 and the inner wall of the through hole 2, and the diffusion layer 3 of the electrode 4A connected to the diffusion layer 3 is formed. And the semiconductor film 1 of the other electrode 4B
After the portion other than the contact portion is covered with a resist and the insulating film 12 is etched, the electrode 4A connected to the diffusion layer 3 and the other electrode 4B are formed. As described above, the insulating film 12 at this time may be an anti-reflection film in the case of a solar cell.

Embodiment 13 FIG. As described above, the diffusion layer 3 is provided on the front surface of the semiconductor film 1, the inner wall of the through hole 2 extending from the front surface to the back surface, and the peripheral portion of the opening of the through hole 2 of the semiconductor film 1, and the electrode connected to the diffusion layer 3 A semiconductor device having a structure in which both the electrode 4 and the other electrode 4 are provided on the back side of the semiconductor film 1 is manufactured. A current-voltage curve representing the performance when a solar cell is manufactured using this structure. FIG. 12 shows the fill factor.

FIG. 12A shows a case where the arrangement pattern of the through holes 2 is a lattice pattern using a square as a minimum unit, and FIG. 12B shows a case where the regular triangle is the minimum unit. ing. In order to obtain a sufficiently excellent performance as a solar cell, a fill factor of about 0.78 or more is required. From this figure, it can be seen from this figure that in any case, the arrangement pitch of the through holes 2 is large. It can be seen that it is necessary to be 1.5 mm or less and the resistance value between the front and back of the semiconductor film 1 in the through hole 2 is 10 Ω or less.

In each of the above embodiments, mainly
Although the case where silicon is used as the material of the substrate 100 and the semiconductor film 1 has been described, other materials may be used, and the same effect is obtained.

[0122]

As described above, the semiconductor device according to the first aspect of the present invention is provided on the surface of the semiconductor film, the inner wall of the through hole extending from the surface to the back surface, and the periphery of the through hole on the back surface of the semiconductor film. In a semiconductor device having a structure in which a diffusion layer is provided, and both an electrode connected to the diffusion layer and an electrode of the other electrode are provided on a back surface side of the semiconductor film,
Since the semiconductor film was covered with an insulating film except for a contact portion of the electrode connected to the diffusion layer to the diffusion layer and a contact portion of the other electrode to the semiconductor film, the region of the diffusion layer This has the effect that the area can be reduced and the performance of the semiconductor device can be improved. Further, since the insulating film is used as an antireflection film of a semiconductor device, the number of steps is reduced in the case of manufacturing a solar cell, and the effect of improving productivity and yield can be obtained. Further, the thickness of the semiconductor film is set to 1
00 μm or less, between the front and back of the semiconductor film of the through hole
The electric resistance is 10Ω or less per one, and the through hole is
Since they are arranged at a pitch of 1.5 mm or less, there is an effect that sufficiently excellent performance as a solar cell can be obtained.

Manufacturing of a semiconductor device according to claim 2 of the present invention .
The fabrication method is, as described above, the surface of the semiconductor film,
Inner wall of a through hole reaching from the front surface to the back surface, and the semiconductor film
Including a step of providing a diffusion layer around a through hole on the back surface of the semiconductor
In the method of manufacturing a body device, the front surface, the back surface, and the front
After forming an insulating film on the inner wall of the through hole, the diffusion layer is provided.
Removing the insulating film in the region other than the region to
Exposing the film and using the remaining insulating film as a mask, the semiconductor
By etching the film, the pattern of the diffusion layer
Resist is formed on the back side of the semiconductor film.
Just improve productivity and yield.
This has the effect. Further, the insulating film may be used as a semiconductor device.
The use of an anti-reflection coating reduces the number of processes for solar cells.
Has the effect of improving productivity and yield.
You .

The manufacturing of the semiconductor device according to claim 3 of the present invention .
The fabrication method is, as described above, the surface of the semiconductor film,
Inner wall of a through hole reaching from the front surface to the back surface, and the semiconductor film
Including a step of providing a diffusion layer around a through hole on the back surface of the semiconductor
In the method of manufacturing a body device, the front surface, the back surface, and the front
After forming an insulating film on the inner wall of the through hole, the shape of the diffusion layer
Removing the insulating film according to the formed pattern and forming the semiconductor film
And forming the diffusion layer by impurity diffusion.
The semiconductor film itself for patterning the diffusion layer.
No need to chin and do not damage the surface
In addition, a diffusion layer can be formed only on the periphery of the through hole opening on the back surface.
This has the effect. In addition, the diffusion layer was formed and remained.
After removing the insulating film, the front surface, the rear surface, and the penetration
Form another insulating layer on the inner wall of the hole and connect to the diffusion layer
Contact of the electrode with the diffusion layer and half of the electrode of the other electrode
After removing the another insulating film at the contact portion to the conductor film,
Form the electrode connected to the diffusion layer and the other electrode
Manufacturing process to produce equipment with excellent performance.
Has the effect of improving productivity and yield.
You. Further, the insulating film is deposited by a CVD method.
Etching is easy because of the silicon oxide film
And is advantageous in terms of consistency with other processes.
Play a fruit. Still further, the thickness of the silicon oxide film
Is 1000 Å or more,
Etched by light etching before diffusion
There is an effect that there is no .

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[Brief description of the drawings]

FIG. 1 is a diagram illustrating a method for manufacturing a semiconductor device according to a first embodiment of the present invention.

FIG. 2 is a schematic sectional view showing an apparatus for manufacturing a semiconductor device according to a second embodiment of the present invention.

FIG. 3 is a schematic sectional view showing an apparatus for manufacturing a semiconductor device according to a third embodiment of the present invention.

FIG. 4 is a schematic front view showing a semiconductor device manufacturing apparatus according to Embodiment 4 of the present invention.

FIG. 5 is a schematic sectional view showing an apparatus for manufacturing a semiconductor device according to a sixth embodiment of the present invention.

FIG. 6 is a schematic view showing an apparatus for manufacturing a semiconductor device according to a seventh embodiment of the present invention.

FIG. 7 is a schematic view illustrating a method for manufacturing a semiconductor device according to an eighth embodiment of the present invention.

FIG. 8 is a schematic diagram showing an apparatus for manufacturing a semiconductor device according to a ninth embodiment of the present invention.

FIG. 9 is a schematic sectional view illustrating a method for manufacturing a semiconductor device according to Example 10 of the present invention.

FIG. 10 is a diagram showing a semiconductor device according to Embodiment 11 of the present invention.

FIG. 11 is a schematic sectional view illustrating a method for manufacturing a semiconductor device according to Example 12 of the present invention;

FIG. 12 is a diagram showing a current-voltage characteristic curve of a semiconductor device according to Embodiment 13 of the present invention.

FIG. 13 is a schematic view illustrating a conventional method for manufacturing a semiconductor device.

FIG. 14 is a schematic view illustrating a conventional method for manufacturing a semiconductor device.

FIG. 15 is a diagram showing a conventional semiconductor device manufacturing apparatus.

FIG. 16 is a view showing a conventional semiconductor device manufacturing apparatus.

FIG. 17 is a view illustrating a conventional method of manufacturing a semiconductor device.

FIG. 18 is a view showing a conventional semiconductor device.

[Explanation of symbols]

1 semiconductor film, 2 through hole, 3 diffusion layer, 4A, 4B
Electrode, 10 release layer, 11 water, 12 insulating film, 21
1st area | region, 22 2nd area | region, 31 and 31A 1st space, 32 and 32A 2nd space, 614 mesh made of tetrafluoroethylene resin, 100 board | substrates, 112 2nd insulating film.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 31/04-31/078

Claims (3)

(57) [Claims] 1. A front surface of a semiconductor film, from the front surface to a back surface.
Inner wall of the through hole, and the through hole on the back surface of the semiconductor film.
A diffusion layer is provided in the periphery and connected to the diffusion layer.
Both the electrode and the other electrode of the semiconductor film
In a semiconductor device having a structure provided on a back surface side, a contact portion of an electrode connected to the diffusion layer with the diffusion layer may be formed.
Except for the contact of the electrode of the other pole with the semiconductor film
An anti-reflection film made of a silicon nitride film
Covered withA thickness of the semiconductor film is 100 μm or less; One electric resistance between the front and back of the semiconductor film in the through hole hits
10Ω or less, The through hole is 1.5 mm or less
Arranged in pitchingA semiconductor device characterized by the above-mentioned. 2. A method of manufacturing a semiconductor device, comprising: providing a front surface of a semiconductor film, an inner wall of a through hole reaching from the front surface to the back surface, and a diffusion layer around the through hole on the back surface of the semiconductor film. After forming an anti-reflection film made of a silicon nitride film on the back surface and the inner wall of the through hole, the anti-reflection film in a region other than the region where the diffusion layer is to be provided is removed to expose the semiconductor film, and the remaining reflection film is formed. A method of manufacturing a semiconductor device, wherein a pattern of the diffusion layer is formed by etching the semiconductor film using a prevention film as a mask. 3. A method of manufacturing a semiconductor device, comprising: providing a front surface of a semiconductor film, an inner wall of a through hole extending from the front surface to the back surface, and a diffusion layer around the through hole on the back surface of the semiconductor film. After forming an insulating film made of a silicon oxide film having a thickness of 1000 Å or more deposited on the back surface and the inner wall of the through hole by a CVD method, the insulating film is removed according to a pattern of forming the diffusion layer, and the semiconductor film is removed. After the film is exposed and the diffusion layer is formed by impurity diffusion, after forming the diffusion layer and removing the remaining insulating film, an antireflection film made of a silicon nitride film is formed on the front surface, the rear surface, and the inner wall of the through hole. Forming and removing the antireflection film at the contact portion of the electrode connected to the diffusion layer to the diffusion layer and the contact portion of the other electrode to the semiconductor film, The method of manufacturing a semiconductor device characterized by forming the electrodes of the connected electrode and the other electrode.