JP2023060555A - Method for manufacturing passivation film, semiconductor substrate with passivation film and semiconductor element - Google Patents

Abstract

To provide a method for manufacturing a passivation film, a semiconductor substrate with a passivation film, and a semiconductor device that improves passivation performance without adjusting the film deposition temperature.SOLUTION: It is a method for manufacturing passivation films 10a and 10b having a precursor film growth process in which a precursor film is deposited by growing hydrogenated amorphous silicon to a set film thickness on one side of a semiconductor substrate 20. The manufacturing method has a plasma treatment process in which a plasma treatment using argon is applied to the semiconductor substrate 20 on which the precursor film is deposited as a post-treatment of the precursor film growth process.SELECTED DRAWING: Figure 1

Description

The present invention relates to a method of manufacturing a passivation film for protecting the surface of a semiconductor element, a semiconductor substrate with a passivation film, and a semiconductor element.

Semiconductor elements used in solar cells, image sensors, OLEDs (organic light emitting diodes), etc. are used with passivation films formed on their surfaces (see, for example, Patent Document 1). Patent Document 1 discloses a solar cell in which passivation films are formed on both surfaces of an n-type single crystal silicon wafer.

Since a semiconductor element made of crystalline silicon or the like has defects on a part of its surface, it is important for the semiconductor device to inactivate (terminate) the defects on the surface of the semiconductor element. Passivation of defects on the surface of a semiconductor element is also called passivation. That is, the passivation film is a protective film formed on the surface of a semiconductor element in order to improve the passivation performance of the semiconductor element.

JP 2021-57436 A

However, when a passivation film is formed on a semiconductor substrate using a conventional technique such as that disclosed in Patent Document 1, a film formation temperature of 160° C. or higher is required to inactivate the crystalline silicon surface. In other words, it has been conventionally said that the performance of a passivation film is good or bad depending on the film formation temperature, and the actual situation is that there is no method for improving the passivation performance other than setting the optimum film formation temperature.

The present invention has been made to solve the above problems, and provides a method for manufacturing a passivation film, a semiconductor substrate with a passivation film, and a semiconductor element that improve passivation performance without adjusting the film formation temperature. intended to

A method for manufacturing a passivation film according to an aspect of the present invention includes a precursor film growing step of growing hydrogenated amorphous silicon to a set film thickness on one surface of a semiconductor substrate to form a precursor film; and a plasma treatment step of applying a plasma treatment using argon to the semiconductor substrate on which the is deposited.

A semiconductor substrate with a passivation film according to an aspect of the present invention has a semiconductor substrate and a passivation film formed on one surface or both surfaces of the semiconductor substrate using the above method.
A semiconductor device according to an aspect of the present invention has a semiconductor substrate and a passivation film formed on one or both surfaces of the semiconductor substrate using the above method.

According to the present invention, since plasma processing is performed on a semiconductor substrate having a precursor film formed of hydrogenated amorphous silicon, passivation performance can be improved without adjusting the film formation temperature.

1 is a schematic cross-sectional view showing a configuration example of a semiconductor device according to an embodiment of the present invention; FIG. FIG. 4 is an explanatory diagram illustrating a state of a precursor film growing step in the manufacturing steps of the passivation film and the semiconductor substrate with the passivation film according to the embodiment of the present invention; FIG. 4 is an explanatory diagram illustrating a state of a plasma processing step among the steps of manufacturing a passivation film and a semiconductor substrate with a passivation film according to an embodiment of the present invention; 4 is a configuration diagram illustrating a plasma processing apparatus used for the plasma processing of FIG. 3; FIG. 1 is a schematic cross-sectional view illustrating a passivation film and a semiconductor substrate with a passivation film according to an embodiment of the present invention; FIG. FIG. 4 is an explanatory diagram illustrating a state of a precursor film growth step among the steps of manufacturing a semiconductor substrate with a passivation film for verifying the performance of the passivation film according to the embodiment of the present invention; FIG. 4 is an explanatory diagram illustrating a state of a plasma processing step among manufacturing steps of a semiconductor substrate with a passivation film for verifying performance of the passivation film according to the embodiment of the present invention; 8 is a schematic cross-sectional view illustrating a passivation film and a semiconductor substrate with a passivation film manufactured through the precursor film growth step of FIG. 6 and the plasma treatment step of FIG. 7; FIG. 5 is a graph showing a difference in photocurrent before and after plasma processing in relation to the manufacturing process of the passivation film and the passivation film-attached semiconductor substrate according to the embodiment of the present invention; 4 is a graph showing the relationship between supplied power and photocurrent in plasma processing. 4 is a graph showing the relationship between plasma processing time and photocurrent.

Embodiment.
A configuration example of a semiconductor element 100, a semiconductor substrate 21 with a passivation film, and a passivation film 10 according to an embodiment of the present invention will be described with reference to FIG. In FIG. 1, a heterojunction solar cell element is illustrated as the semiconductor element 100, and a first passivation film 10a and a second passivation film 10b are illustrated as the passivation film 10. FIG.

As shown in FIG. 1, a semiconductor element 100 has a semiconductor substrate 21 with a passivation film. A semiconductor substrate 21 with a passivation film includes a semiconductor substrate 20, a first passivation film 10a formed on one surface of the semiconductor substrate 20, and a second passivation film 10b formed on the other surface of the semiconductor substrate 20. have. The semiconductor device 100 has a p-type amorphous silicon layer 30 formed on the second passivation film 10b. The semiconductor device 100 has an n-type amorphous silicon layer 40 formed on the first passivation film 10a.

The semiconductor device 100 has a transparent conductive layer 51 formed on the n-type amorphous silicon layer 40 and a transparent conductive layer 52 formed on the p-type amorphous silicon layer 30 . The semiconductor element 100 has an electrode group 61 composed of a plurality of collector electrodes 61 a formed on a transparent conductive layer 51 and an electrode group 62 composed of a plurality of collector electrodes 62 formed on a transparent conductive layer 52 . ing. The collector electrode 61a and the collector electrode 62a are composed of finger electrodes formed in a thin wire shape. Here, since light is mainly incident on the semiconductor element 100, which is a solar cell element, from the surface on the transparent conductive layer 51 side, this surface is referred to as the "light receiving surface", and the surface on the transparent conductive layer 52 side is referred to as the "back surface". do.

The semiconductor substrate 20 is composed of, for example, an n-type single crystal silicon wafer. When the semiconductor element 100 is a solar cell element, the semiconductor substrate 20 is formed to have a thickness of, for example, approximately 50 μm to 300 μm. The semiconductor substrate 20 preferably has a textured structure (concavo-convex structure) formed on at least one of the front surface and the back surface to suppress reflection of light and increase the amount of light absorbed.

The first passivation film 10a and the second passivation film 10b are composed of hydrogenated amorphous silicon (a-Si:H). Passivation is to terminate defects on the surface of a semiconductor element and electrically passivate the defects. Techniques for enhancing the passivation performance of semiconductor elements are essential elemental techniques for improving the performance of various devices such as solar cells, image sensors, and OLEDs. In other words, the improvement of the passivation performance of the passivation film directly leads to the improvement of the performance of various devices.

As a material for the first passivation film 10a and the second passivation film 10b, i-type hydrogenated amorphous silicon (ia-Si:H) can be preferably used. Here, i-type (intrinsic) means a material that is not doped with an n-type or p-type dopant. The i-type semiconductor means an intrinsic semiconductor to which no dopant is added.

The first passivation film 10 a suppresses recombination of carriers on the light receiving surface side of the semiconductor element 100 . The thickness of the first passivation film 10a is preferably about 1 nm to 25 nm, more preferably about 5 nm to 10 nm, from the viewpoints of light transmittance, passivation performance, resistance reduction, and the like. The second passivation film 10 b suppresses recombination of carriers on the back side of the semiconductor element 100 . The thickness of the second passivation film 10b is preferably about 1 nm to 25 nm, more preferably about 5 nm to 10 nm, from the viewpoint of passivation performance and resistance reduction.

The thickness of the p-type amorphous silicon layer 30 is preferably about 1 nm to 25 nm, more preferably about 5 nm to 10 nm, from the viewpoint of carrier separation and resistance reduction. The thickness of the n-type amorphous silicon layer 40 is preferably 5 nm or less, more preferably 3 nm or less, and may be 1 nm or less. The n-type amorphous silicon layer 40 acts to suppress oxidation on the surface of the first passivation film 10a. Therefore, by forming the n-type amorphous silicon layer 40 on the first passivation film 10a, the output characteristics of the semiconductor element 100 can be improved.

The transparent conductive layer 51 and the transparent conductive layer 52 are made of transparent metal oxides such as indium oxide (In203) and zinc oxide (ZnO) doped with tungsten (W), tin (Sn), antimony (Sb), and the like. It is composed of a conductive oxide (IWO, ITO, etc.). The transparent conductive layer 51 and the transparent conductive layer 52 may have a thickness of, for example, about 30 nm to 500 nm, and more preferable characteristics can be obtained with a thickness of about 50 nm to 200 nm.

In the electrode group 61, a plurality of collecting electrodes 61a are provided so as to be parallel to each other at predetermined intervals. Although FIG. 1 illustrates an electrode group 61 having three collector electrodes 61a, the number of collector electrodes 61a is not limited to this example. Also in the electrode group 62, a plurality of collecting electrodes 62a are provided so as to be parallel to each other at predetermined intervals. Although FIG. 1 illustrates an electrode group 62 having seven collector electrodes 62a, the number of collector electrodes 62a is not limited to this example.

Next, a method for manufacturing the passivation film 10 and the passivation film-attached semiconductor substrate 21 according to the present embodiment will be specifically described with reference to FIGS. Note that the first passivation film 10a and the second passivation film 10b in the semiconductor element 100 of FIG.

[Precursor film growth step]
First, as shown in FIG. 2, a precursor film 10k is formed on one surface of a semiconductor substrate 20 by growing hydrogenated amorphous silicon to a set film thickness by plasma chemical vapor deposition. As the material of the precursor film 10k, i-type hydrogenated amorphous silicon (ia-Si:H) can be preferably used. The set film thickness is a thickness set in advance within the range of 5 nm to 20 nm, and is set to 17 nm, for example. As a result, a precursor film 10k, which is a single-layer film of hydrogenated amorphous silicon, is formed on one surface of the semiconductor substrate 20. Next, as shown in FIG. In FIG. 2, defects at the interface between the semiconductor substrate 20 and the precursor film 10k are indicated by x marks. Passivation performance deteriorates as interface defects increase.

When hydrogenated amorphous silicon is used as the material of the passivation film, the conventional technique requires the film formation temperature of the passivation film to be 160° C. or higher. On the other hand, since the present manufacturing method has a plasma treatment step to be described later, even if the precursor film 10k is formed at 100° C. or less, the passivation film 10 having good passivation performance can be obtained by plasma treatment as a post-treatment. can be manufactured. In the precursor film growth step in the present embodiment, the precursor film 10k is formed on the semiconductor substrate 20 at a film formation temperature of 60°C to 100°C, or 160°C to 240°C. Regarding the deposition temperature of the precursor film 10k, if it is 70° C. or higher and 90° C. or lower, better passivation performance can be obtained in the subsequent plasma treatment. Passivation performance can be drawn out.

[Plasma treatment process]
Next, as shown in FIG. 3, the film-coated substrate 21k, which is the semiconductor substrate 20 on which the precursor film 10k is formed, is subjected to plasma treatment using, for example, argon (Ar) (so-called argon plasma treatment). Plasma processing is performed by a plasma processing apparatus 80 as illustrated in FIG. In the case of argon plasma processing, the surface of the precursor film 10k is bombarded with argon ions using the plasma processing apparatus 80. FIG.

The plasma processing apparatus 80 of FIG. 4 is a parallel plate type plasma processing apparatus. As shown in FIG. 4, the plasma processing apparatus 80 has a chamber 81, and a lower electrode 82 and an upper electrode 83 arranged in the chamber 81 and facing each other. The chamber 81 is a processing chamber that can be vacuum-tight. An object to be plasma-processed can be placed on the upper side of the lower electrode 82 . FIG. 4 illustrates a film-coated substrate 21k as an object to be processed. The lower electrode 82 may have a configuration in which a heating means such as a heater is provided inside. High-frequency power can be supplied (applied) between the lower electrode 82 and the upper electrode 83 by a high-frequency power supply 84 or the like provided outside the chamber 81 . FIG. 4 shows an example in which a ground potential is connected to the lower electrode 82 and a high frequency power source 84 is connected to the upper electrode 83 . The frequency of the high frequency power supplied from the high frequency power supply 84 is, for example, 13.56 MHz. The frequency of the high frequency power supplied from the high frequency power supply 84 may be 27 MHz or the like.

The chamber 81 is provided with a gas supply port 85 and a gas exhaust port 86 . A desired gas (gas for plasma processing) can be introduced into the chamber 81 through the gas supply port 85 . Gas and the like in the chamber 81 are exhausted from the gas exhaust port 86 . The chamber 81 is connected through a gas exhaust port 86 to a gas exhaust unit (not shown) such as a vacuum pump. The plasma processing apparatus 80 controls the pressure inside the chamber 81 by adjusting the exhaust speed from the gas exhaust port 86 according to the pressure inside the chamber 81 detected by a pressure sensor (not shown) or the like to maintain the inside of the chamber 81 at a desired pressure. You may have a part (not shown). Hereinafter, the high-frequency power supplied to the object to be processed in the plasma processing apparatus 80 is also referred to as supplied power.

Next, with reference to FIGS. 6 to 8, the configuration and manufacturing method of a semiconductor substrate with a passivation film for verifying the performance of the passivation film according to this embodiment will be described. First, as shown in FIG. 6, a buried oxide (BOX) 91 with a thickness of 500 nm is formed on one surface of a silicon wafer with a thickness of 725 μm as the semiconductor substrate 20, and then a silicon active layer with a thickness of 300 nm is formed. A layer (SOI: silicon on insulator) 92 was produced. Then, hydrogenated amorphous silicon was grown to 15 nm by plasma chemical vapor deposition to form a precursor film 10k. Here, as shown in FIG. 6, the element in which the buried oxide film 91, the silicon active layer 92, and the precursor film 10k are laminated in this order on the semiconductor substrate 20 is called a film-attached semiconductor substrate 210k. For the precursor film 10k and the film-attached semiconductor substrate 210k, the same name and the same reference numerals are used until the plasma processing is completed.

In FIG. 6, defects at the interface between the silicon active layer 92 and the precursor film 10k are indicated by x marks. The precursor film 10k was formed by changing the film formation temperature stepwise in the range of 60° C. to 280° C., and the photocurrent in the film-attached semiconductor substrate 210k corresponding to each temperature was measured. The measurement results are indicated by white circles in FIG. In FIG. 9, the polygonal line plotted with these white circles is indicated as "growth". The film-attached semiconductor substrate 210 k is a prototype as a comparative example for verifying the performance of the passivation film 10 .

Next, the precursor film 10k formed as described above was subjected to argon plasma treatment using the plasma treatment apparatus 80. FIG. The processing conditions are as follows. That is, high-frequency discharge of 60 MHz was used, and the supplied power (processing power) was changed stepwise in the range of 5 W to 50 W (see FIG. 10). In addition, the treatment time was varied stepwise within the range of 1 s to 100 s (see FIG. 11). The distance between electrodes (the distance between the lower electrode 82 and the upper electrode 83) of the plasma processing apparatus 80 was set to 22 mm. Electrodes having a diameter of 128 mm were used as the lower electrode 82 and the upper electrode 83 . The processing temperature was changed stepwise in the range of 60° C. to 280° C. in accordance with the deposition temperature of the precursor film 10k. Hereinafter, the processing temperature of plasma processing is also referred to as “plasma processing temperature”.

During plasma processing, defects at the interface between silicon active layer 92 and precursor film 10k increase, as illustrated in FIG. On the other hand, when the plasma treatment is finished, as illustrated in FIG. 8, defects at the interface between the silicon active layer 92 and the precursor film 10k are reduced, and passivation performance of the surface of the silicon active layer 92 is improved. This is believed to be caused by the hydrogenated amorphous silicon in the precursor film 10k stimulated by the plasma treatment acting on the defects. That is, it is presumed that the plasma treatment activated the self-healing function of hydrogenated amorphous silicon.

The plasma treatment was performed on all the film-coated substrates 210k having the precursor films 10k formed at respective film formation temperatures of 60.degree. C. to 280.degree. In the present embodiment, plasma processing is performed on the film-coated substrate 210k at a temperature equal to the film formation temperature of the precursor film 10k, and a prototype for verifying the performance of the passivation film is configured as illustrated in FIG. A plurality of semiconductor substrates 210 with passivation films were manufactured. Then, the photocurrent in each semiconductor substrate 210 with a passivation film was measured. The measurement results are indicated by rhombuses (black) in FIG. In FIG. 9, the polygonal line plotting these rhombuses is denoted as "Ar".

In the case of the semiconductor substrate 21 with the passivation film and the semiconductor element 100 shown in FIG. 1, the precursor film growth step is to grow hydrogenated amorphous silicon to a set film thickness on one surface of the semiconductor substrate 20 to form the precursor film 10k. A first film growth step for forming a film, and a second film growth step for forming the precursor film 10k by growing hydrogenated amorphous silicon to a set film thickness on the other surface of the semiconductor substrate 20. . Then, in the plasma processing step, the semiconductor substrate 20 having the precursor films 10k formed on both surfaces thereof is subjected to plasma processing from each surface side.

Next, with reference to FIGS. 9 to 11, changes in passivation performance due to plasma processing steps will be described. A large photocurrent value indicates that there are few defects on the surface of the silicon active layer 92 and that the passivation performance of the surface layer film is high. Therefore, as shown in FIGS. 9 to 11, the photocurrent (Ip) is plotted on the vertical axis, and the relationship between the film formation temperature, the power supplied in the plasma treatment, and the processing time of the plasma treatment and the photocurrent was verified. . In FIG. 9, the horizontal axis represents the film formation temperature, and the vertical axis represents the photocurrent. In FIG. 10, the horizontal axis represents the power supplied in plasma processing, and the vertical axis represents the photocurrent. In FIG. 11, the horizontal axis represents the plasma processing time, and the vertical axis represents the photocurrent.

FIG. 9 shows the dependence of the photocurrent in the film-coated substrate 210k and the passivation-coated semiconductor substrate 210 on the film formation temperature and the plasma processing temperature. First, from the graph of the film-coated substrate 210k, if the argon plasma treatment is not performed, the photocurrent exceeds 1 μA only when the film-forming temperature is within the range of about 160° C. to 210° C. It can be confirmed that passivation performance cannot be ensured. Note that the photocurrent value (white circle) before the argon plasma treatment reaches its maximum around 180 degrees, which indicates that the passivation performance of the precursor film 10k reaches its maximum around 180 degrees. On the other hand, it can be confirmed that the passivation performance of the precursor film 10k is remarkably low when the film formation temperature is in the low temperature range of 100° C. or lower (especially near 80° C.).

On the other hand, it can be confirmed from the graph of the semiconductor substrate 210 with a passivation film that the argon plasma treatment increased the photocurrent over the entire temperature range, that is, the passivation performance was improved over the entire temperature range. That is, it is presumed that a new passivation performance was added due to the action of the argon plasma treatment.

Furthermore, in the case of the semiconductor substrate 210 with a passivation film, the photocurrent exceeds 2 μA when the film formation temperature is in the range of about 60.degree. C. to 100.degree. In other words, the semiconductor substrate 210 with a passivation film formed at a film formation temperature of about 60° C. to 100° C. has passivation performance that is comparable to the substrate 210k with a film formed by forming the precursor film 10k at about 180° C., or is greatly improved. Exceed. More specifically, in the semiconductor substrate 210 with a passivation film, the passivation performance of the passivation film 10 is equal to the passivation performance of the precursor film 10k on the substrate 210k with the passivation film if the deposition temperature is within the range of about 70°C to 90°C. greatly surpasses Especially when the film formation temperature is 80° C., it can be confirmed that the passivation performance of the passivation film 10 is dramatically improved compared to the precursor film 10k.

In this embodiment, the power supplied in the argon plasma treatment was changed in the range of 5W to 50W. From FIG. 10, it can be confirmed that the photocurrent increases as the processing power increases within the above range. FIG. 10 shows data when the argon plasma treatment was performed for 1 second (1 second) with each power supply. In the range of FIG. 10, the photocurrent is maximized when the supplied power in the argon plasma treatment is 50 W, which confirms that the passivation performance at this time is the best.

Therefore, the power supplied in the argon plasma treatment was set to 50 W, and the photocurrent was measured while increasing the treatment time of the argon plasma treatment stepwise from 1 s. The result is the graph shown in FIG. From FIG. 11, it can be confirmed that the photocurrent decreases as the treatment time of the argon plasma treatment is increased. This is presumed to be because when the processing time of the argon plasma treatment increases, argon ions are excessively implanted into the precursor film 10k, the defects of the precursor film 10k increase, and the passivation performance of the precursor film 10k deteriorates. be.

As described above, the method of manufacturing the passivation film 10 according to the present embodiment is a precursor film growth method in which hydrogenated amorphous silicon is grown to a set film thickness on one surface of the semiconductor substrate 20 to form the precursor film 10k. and a plasma treatment step of applying plasma treatment to the semiconductor substrate 20 on which the precursor film 10k is formed. Therefore, the hydrogenated amorphous silicon in the precursor film 10k formed in the precursor film growth step is stimulated by the gas used in the plasma treatment, and the self-repairing function of the precursor film 10k is activated. The passivation performance can be improved regardless of the film formation temperature. That is, the plasma treatment can passivate the surface of the semiconductor substrate 20 made of, for example, crystalline silicon.

By the way, although the argon plasma treatment has been exemplified in the above description, the present invention is not limited to this. For example, in the plasma processing step, the semiconductor substrate 20 on which the precursor film 10k is formed is subjected to plasma processing using a mixed gas of argon and one or more other rare gases (group 18 elements). may As rare gases, in addition to Ar (argon/atomic number 18/mass number ≈ 39.948), He (helium/atomic number 2/mass number ≈ 4.0026), Kr (krypton/atomic number 36/mass number ≈83.798), Xn (xenon/atomic number 54/mass number≈131.293). Further, in the plasma processing step, the semiconductor substrate 20 on which the precursor film 10k is formed may be subjected to plasma processing using one or a plurality of rare gases other than argon.

However, as described above, when the semiconductor substrate 20 is formed of silicon, the rare gas used for the plasma treatment should have a mass number closest to that of silicon (atomic number 14/mass number≈28.085) and Argon having the same period (period 3) as is more preferable. However, in the plasma processing step, a gas obtained by mixing one or a plurality of rare gases with H (hydrogen/atomic number 1/mass number≈1.00798) is used for the semiconductor substrate 20 on which the precursor film 10k is formed. Plasma treatment may be applied.

Since the method of manufacturing passivation film 10 in the present embodiment includes plasma treatment as a post-treatment of the precursor film growth step, as shown in FIG. Sufficient passivation performance can be obtained even if it is less than the degree. If the deposition temperature of the precursor film 10k is 70° C. or more and 90° C. or less, the passivation performance can be further improved. can be improved. In this way, the passivation film 10 can be formed at a low film formation temperature, so that it can be suitably used for elements with low heat resistance, such as relatively thin flexible substrates and resins.

Further, from FIGS. 10 and 11, it can be seen that the passivation performance can be rapidly and accurately improved by setting the power supply in the plasma treatment to 50 W and the processing time of the plasma treatment to 1 second. However, even if the power supply is set to less than 50 W, it is presumed that similar passivation performance can be obtained if the processing time is lengthened.

The set film thickness of the precursor film 10k is preferably 5 nm to 20 nm. The reason why the lower limit of the set film thickness is set to 5 nm is that a thin film of less than 5 nm has many defects from the viewpoint of film characteristics, and the passivation performance is remarkably deteriorated. The reason why the upper limit of the set film thickness is 20 nm is that if the film thickness exceeds 20 nm, the parasitic absorption of the passivation film 10 based on the precursor film 10 k increases, and light does not reach the semiconductor substrate 20 . This is because the transmittance of the passivation film 10 is lowered. Therefore, the precursor film 10k is preferably a thin film having a film thickness of 5 nm or more and 20 nm or less.

Here, the above-described embodiments are specific examples of the passivation film, the semiconductor substrate with the passivation film, the solar cell element, and the method of forming the passivation film, and the technical scope of the present invention is limited to these aspects. not something. For example, in the embodiment described above, i-type hydrogenated amorphous silicon is suitable as the material of the passivation film 10 (10a, 10b), but the material is not limited to this. As a material for the passivation film 10 (10a, 10b), n-type hydrogenated amorphous silicon (na-Si:H) or p-type hydrogenated amorphous silicon (na-Si:H) can be adopted. . However, from the viewpoint of passivation performance, i-type hydrogenated amorphous silicon is preferable to n-type and p-type hydrogenated amorphous silicon. In the semiconductor device 100 shown in FIG. 1, when n-type hydrogenated amorphous silicon is used as the material of the passivation films 10a and 10b, the n-type amorphous silicon layer 40 becomes unnecessary, and p-type hydrogenated amorphous silicon is used. If silicon is used, the p-type amorphous silicon layer 30 becomes unnecessary.

The configuration and structure of each layer of the semiconductor device 100 in FIG. 1 can be changed as appropriate. The passivation film 10 and the semiconductor substrate 21 with a passivation film can also be applied to back-contact solar cells, and can also be applied to semiconductor devices such as image sensors and OLEDs. That is, the method of manufacturing the passivation film 10 may be employed in the manufacturing process of other types of solar cell elements such as back-contact solar cell elements, the manufacturing process of back-illuminated image sensors, and the manufacturing process of OLEDs. It may also be employed in the manufacturing process of the exit surface.

10, 10a, 10b passivation film, 10k precursor film, 20 semiconductor substrate, 21, 210 semiconductor substrate with passivation film, 21k, 210k substrate with film, 30 p-type amorphous silicon layer, 40 n-type amorphous silicon layer , 51, 52 transparent electrode layer, 61, 62 electrode group, 61a, 62a collecting electrode, 80 plasma processing apparatus, 81 chamber, 82 lower electrode, 83 upper electrode, 84 high frequency power source, 85 gas supply port, 86 gas exhaust port.

Claims (8)

a precursor film growth step of growing amorphous silicon hydride to a set film thickness on one surface of a semiconductor substrate to form a precursor film;
and a plasma treatment step of performing plasma treatment using argon on the semiconductor substrate on which the precursor film is formed. a precursor film growth step of growing amorphous silicon hydride to a set film thickness on one surface of a semiconductor substrate to form a precursor film;
A method of manufacturing a passivation film, comprising a plasma treatment step of subjecting the semiconductor substrate on which the precursor film is formed to plasma treatment using a mixed gas of argon and one or more other rare gases. a precursor film growth step of growing amorphous silicon hydride to a set film thickness on one surface of a semiconductor substrate to form a precursor film;
A method of manufacturing a passivation film, comprising a plasma treatment step of subjecting the semiconductor substrate on which the precursor film is formed to plasma treatment using one or more rare gases. 4. The method for manufacturing a passivation film according to claim 1, wherein the film forming temperature of said precursor film in said precursor film growing step is 60 degrees or more and 100 degrees or less. In the plasma treatment step,
5. The method for manufacturing a passivation film according to claim 1, wherein power supplied in said plasma treatment is 50 W, and treatment time of said plasma treatment is 1 second. 6. The method for manufacturing a passivation film according to claim 1, wherein said set film thickness is 5 nm to 20 nm. a semiconductor substrate;
A semiconductor substrate with a passivation film, comprising a passivation film formed on one or both surfaces of the semiconductor substrate by using the method according to any one of claims 1 to 6. a semiconductor substrate;
and a passivation film formed on one or both surfaces of the semiconductor substrate using the method according to any one of claims 1 to 6.

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