JP2003264148A - Thin-film manufacturing method, semiconductor device manufacturing method, thin film of amorphous semiconductor, thin film of insulator, and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide technique which suppresses the exfoliation of films in a semiconductor process, especially in a thin-film transistor manufacturing process. <P>SOLUTION: This thin-film manufacturing method is provided with a forming process for forming an amorphous semiconductor thin film on a substrate (5), by a PVD (Physical Vapor Deposition) method which uses a rare gas. The concentration of the rare gas contained in the amorphous semiconductor thin film is smaller than 1×10<SP>20</SP>cm<SP>-3</SP>. The reduction of the concentration of the rare gas to a value less than 1×10<SP>20</SP>cm<SP>-3</SP>reduces the quantity of desorption of the rare gas from the amorphous semiconductor thin film in a process performed after the formation of the amorphous semiconductor thin film, and effectively prevents film exfoliation in the process. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thin film manufacturing method. The present invention particularly relates to a thin film manufacturing method including a step of forming a thin film using a PVD method such as a sputtering method or an ion plating method.

[0002]

2. Description of the Related Art In the manufacture of semiconductor devices having thin film transistors integrated, the plasma CVD method is widely used for growing thin films because it is highly necessary to lower the process temperature. The formation of a polycrystalline semiconductor thin film forming a thin film transistor is generally performed by forming an amorphous semiconductor thin film by a plasma CVD method and performing laser annealing on the formed amorphous semiconductor thin film to crystallize it. Further, plasma C is used to grow a silicon oxide film, a silicon nitride film, or a silicon oxynitride film used as an insulating film.
The VD method may be used.

However, a large amount of hydrogen contained in a thin film formed by the plasma CVD method may cause film peeling during the process of semiconductor devices. When an amorphous semiconductor thin film is formed by the plasma CVD method,
Silicon hydride such as silane (SiH ₄ ) and disilane (Si ₂ H ₆ ) is used as a source gas. Therefore, the formed amorphous semiconductor thin film typically has about 1
It contains 0% hydrogen. When laser annealing is performed on such an amorphous semiconductor thin film, hydrogen contained in the amorphous semiconductor thin film is rapidly desorbed. This desorption of hydrogen causes film peeling and makes it difficult to apply the polycrystalline semiconductor thin film to a semiconductor device. Since silicon hydride is used as a source gas also for forming a silicon oxide film, a silicon nitride film, and a silicon oxynitride film, the formed insulating film has 10 to 2
It contains 0% hydrogen. Hydrogen contained in the insulating film may cause film peeling of the insulating film during laser annealing.

In order to prevent peeling of a thin film due to a large amount of contained hydrogen, heat treatment is performed at an appropriate temperature in a heating furnace before laser annealing to gradually desorb hydrogen in the thin film. The method is known. However, in this method, several% of hydrogen remains in the thin film even after the heat treatment, and therefore film peeling is not completely prevented.

From such a background, it has been studied to form a thin film by the sputtering method and avoid the problem of residual hydrogen in the film in the plasma CVD method. Since hydrogen is not used in the sputtering method, hydrogen can be prevented from entering the thin film.

However, the thin film formed by the sputtering method contains a rare gas such as argon used as a sputtering gas. Although this noble gas is not so remarkable as film peeling due to residual hydrogen, it still causes film peeling.

A thin film manufacturing method for suppressing film peeling due to a rare gas contained in a thin film is disclosed in Japanese Patent Laid-Open Publication No.
-186165). In the known thin film manufacturing method, an amorphous semiconductor thin film is formed by a sputtering method, and then the formed amorphous semiconductor thin film is irradiated with ultraviolet light. Unexamined Japanese Patent Publication (JP-A-11-18616)
In 5), the concentration of argon in the amorphous semiconductor thin film formed by the sputtering method is 1 × 10 ²⁰ atoms / cm 3.
^It is disclosed that the number is ³ or more. By irradiating the amorphous semiconductor thin film with ultraviolet light, the argon gas contained in the amorphous semiconductor thin film is desorbed, and the amorphous semiconductor thin film is polycrystallized to form a polycrystalline semiconductor thin film. The known method for manufacturing such a thin film has a concentration of the sputtering gas contained in the finally formed polycrystalline semiconductor thin film of 1 × 10 5.
It is possible to make it less than ²⁰ atoms / cm ³ .

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a technique for further suppressing the occurrence of film peeling in a semiconductor process.

Another object of the present invention is to provide a technique for suppressing the occurrence of film peeling of a semiconductor thin film in a semiconductor process, particularly in a manufacturing process of a thin film transistor.

Still another object of the present invention is to provide a technique for suppressing the occurrence of film peeling of an insulator thin film in a semiconductor process, particularly in a thin film transistor manufacturing process.

[0011]

[Means for Solving the Problems] Means for solving the problems will be described below by using the numbers and symbols used in the embodiments of the present invention. These numbers / codes are added to clarify the correspondence between the description in [Claims] and the description in [Embodiment of the Invention]. However,
The added numbers / codes should not be used to interpret the technical scope of the invention described in [Claims].

The thin film manufacturing method according to the present invention comprises a forming step of forming an amorphous semiconductor thin film (13) on a substrate (5, 11) by a PVD method using a rare gas. The concentration of the rare gas contained in the amorphous semiconductor thin film (13) is 1 × 1.
It is less than 0 ²⁰ cm ⁻³ . Noble gas concentration 1 x 10
The reduction to less than ²⁰ cm ⁻³ is due to the amorphous semiconductor thin film (1
The amount of rare gas released from the amorphous semiconductor thin film (13) in the process performed after the formation of 3) is reduced, and film peeling in the process is effectively prevented.

In the forming step, the amorphous semiconductor thin film (1
It is preferable to include a step of actively reducing the concentration during the formation of 3). It is preferable that the amorphous semiconductor thin film (13) is already reduced before the subsequent process is performed in order to effectively prevent film peeling.

The amorphous semiconductor thin film (13) preferably contains silicon as a main component.

It is preferable that the forming step includes a sputtering step of forming an amorphous semiconductor thin film (13) by a sputtering method.

It is preferable that the sputtering step includes a step of applying a substrate bias to the substrate (5, 11). The application of the substrate bias enables the concentration of the rare gas contained in the amorphous semiconductor thin film (13) to be reduced.

The sputtering process includes a first electrode (2) connected to a target (4) made of a semiconductor material,
Generating a plasma of the rare gas by applying a voltage between the second electrode (9) and the first electrode (2)
Holding the substrate (5, 11) in a space other than the plasma generation space between the second electrode (9) and the second electrode (9), and sputtering the target (4) with the plasma to generate the substrate (5, 11).
It is preferable to provide a step 11) of forming an amorphous semiconductor thin film (13). Such a series of steps is the second step.
Decreasing the plasma density between the electrode (9) and the substrate (5, 11). This reduces the concentration of rare gas ions near the substrate (5, 11) and further reduces the concentration of rare gas contained in the amorphous semiconductor thin film (13).

It is preferable that the forming step includes a step of forming an amorphous semiconductor thin film (13) by an ion plating method.

In the thin film manufacturing method, after the amorphous semiconductor thin film (13) is formed, the amorphous semiconductor thin film (13) is irradiated with laser light (18) and annealed to obtain a polycrystalline semiconductor thin film (19). Is particularly preferable when laser annealing is performed to form (1). The amorphous semiconductor thin film (13) having a low rare gas concentration does not easily peel off even when irradiated with the laser beam (18).

The rare gas preferably contains helium. Helium, which has a low atomic weight, is an amorphous semiconductor thin film (1
It is easily separated from 3), whereby the concentration of the rare gas contained in the amorphous semiconductor thin film (13) can be reduced.

The rare gas preferably contains helium and argon. The inclusion of helium and argon in the rare gas makes it possible to reduce the concentration of the rare gas and to secure the necessary film formation rate.

The thin film manufacturing method according to the present invention comprises an insulator thin film forming step of forming an insulator thin film (12) on a substrate (5, 11) by a PVD (Physical Vapor Deposition) method using a rare gas. The concentration of the rare gas contained in the insulator thin film (12) is less than 5 × 10 ²¹ cm ⁻³ . The reduction of the concentration of the rare gas to less than 5 × 10 ²¹ cm ⁻³ reduces the amount of the rare gas released from the amorphous semiconductor thin film (13) in the process performed after the formation of the insulator thin film (12). Effectively prevent film peeling in the process.

It is preferable that the step of forming the insulator thin film includes a step of actively reducing the concentration of the rare gas during the formation of the insulator thin film (12).

The insulator thin film (12) is preferably formed of one material selected from the group consisting of silicon oxide, silicon nitride and silicon oxynitride.

The insulating thin film forming step preferably includes a sputtering step of forming an insulating thin film (12) by a sputtering method.

It is preferable that the sputtering step includes a step of applying a bias to the substrate (5, 11). The application of the substrate bias enables the concentration of the rare gas contained in the insulator thin film (12) to be reduced.

In the sputtering process, an insulator thin film (12) is used.
Generating a plasma of the rare gas by applying a voltage between the first electrode (2) and the second electrode (9) connected to the target (4) formed of the material forming the And a step of holding the substrate (5, 11) in a space other than the plasma generation space between the first electrode (2) and the second electrode (9), and sputtering the target (4) with the plasma. And a step of forming an insulator thin film (12) on the substrate (5, 11).

The insulating thin film forming step preferably includes a step of forming the insulating thin film (12) by an ion plating method.

The semiconductor device manufacturing method according to the present invention is
The substrate (5, 1) is formed by the first PVD method using the first rare gas.
1) a first step of forming an insulator thin film (12) on the upper surface side, a second step of forming an amorphous semiconductor thin film (13) on the upper surface side of the insulator thin film (12), and an amorphous Semiconductor thin film (1
Laser annealing (3) is performed to irradiate laser light (18) to polycrystallize the amorphous semiconductor thin film (13). Concentration of the first noble gas contained in the insulating thin film (12) is less than 5 × ^{10 2} 1 ^{cm -3.} First
The reduction of the rare gas concentration to less than 5 × 10 ²¹ cm ⁻³ is
The film peeling of the insulator thin film (12) during the irradiation of the laser beam (18) is effectively prevented.

The first PVD method is preferably a sputtering method.

In the second step, when the amorphous semiconductor thin film (13) is formed by the second PVD method using the second rare gas, the second rare gas contained in the amorphous semiconductor thin film (13) is removed. The concentration is preferably less than 1 × 10 ²⁰ cm ⁻³ . 5 × 10 ²¹ cm of the concentration of the first rare gas
The reduction to less than ^-3 effectively prevents film peeling of the amorphous semiconductor thin film (13) during irradiation with the laser beam (18).

The amorphous semiconductor thin film according to the present invention is formed by the PVD method using a rare gas, and the concentration of the rare gas contained therein is less than 1 × 10 ²⁰ cm ⁻³ . The amorphous semiconductor thin film does not easily peel off, and is particularly useful in manufacturing a thin film transistor in which polycrystallization into a polycrystalline semiconductor thin film is performed.

The amorphous semiconductor thin film is preferably formed by a sputtering method using the rare gas as a sputtering gas.

The amorphous semiconductor thin film is preferably formed by an ion plating method using the rare gas.

The amorphous semiconductor thin film preferably contains silicon as a main component.

The insulator thin film according to the present invention is formed by the PVD method using a rare gas, and the concentration of the rare gas contained in the insulator thin film is less than 5 × 10 ²¹ cm ⁻³ .
The insulator thin film does not easily peel off.

The insulator thin film is preferably formed by a sputtering method using the rare gas as a sputtering gas.

The insulator thin film is preferably formed by an ion plating method using the rare gas.

The insulator thin film is preferably formed of one of the group consisting of silicon oxide, silicon nitride and silicon oxynitride.

The semiconductor device according to the present invention comprises a substrate (11)
And an insulating film (12) formed on the upper surface side of the substrate (11)
It has and. The concentration of the rare gas contained in the insulating film (12) is positively suppressed to less than 5 × 10 ²¹ cm ⁻³ .

The semiconductor device further includes an insulating film (12).
It is particularly useful when a polycrystalline semiconductor thin film (19) is formed on the upper surface side of the. The reduction of the concentration of the rare gas contained in the insulating film (12) to less than 5 × 10 ²¹ cm ⁻³ effectively prevents the insulating film (12) from peeling when the polycrystalline semiconductor thin film (19) is formed. Suppress.

The insulating film (12) is formed of P using the rare gas.
It is preferably formed by the VD method, and further preferably formed by the sputtering method.

[0043]

DETAILED DESCRIPTION OF THE INVENTION Referring to the accompanying drawings,
An embodiment of the thin film manufacturing method according to the present invention will be described.

(First Embodiment) In the first embodiment of the method for manufacturing a thin film according to the present invention, a sputtering method is used for forming a thin film. FIG. 1 shows a sputtering apparatus 10 used in the first embodiment. The sputtering apparatus 10 includes a chamber 1. The chamber 1 houses the electrodes 2 and 3 facing each other. A target 4 facing the electrode 3 is joined to the electrode 2. The material of the target 4 is determined according to the thin film to be formed. The electrode 3 holds the substrate 5 so as to face the electrode 2. A heater 6 for heating the substrate 5 is embedded in the electrode 3. The heating of the substrate 5 is kept to the minimum necessary, and the temperature of the substrate 5 is preferably less than 150 ° C.

The electrode 2 is connected to a plasma generating power source 7. The plasma generating power supply 7 applies a DC voltage, a high frequency voltage, or a high frequency voltage on which the DC voltage is superimposed to the electrode 2. The frequency of the high frequency voltage is typically 1
It is 3.56 MHz. Target 4 is silicon oxide
In the case of an insulator such as silicon nitride or silicon oxynitride, a high frequency voltage is applied to the electrode 2. When the target 4 is a material having a certain degree of conductivity such as silicon, either a DC voltage, a high frequency voltage, or a high frequency voltage on which a DC voltage is superimposed can be applied.

The electrode 3 is connected to a plasma generating power source 8. The plasma generating power supply 8 applies a high frequency substrate bias to the substrate 5 via the electrode 3. The frequency of the substrate bias is typically 13.56 MHz.

A piping system for introducing a rare gas and an exhaust pump system for decompressing the chamber 1 are connected to the chamber 1. However, the piping system and the exhaust pump system are not shown. Examples of the rare gas introduced into the chamber 1 include helium, argon, neon, krypton, and xenon.

When forming an amorphous semiconductor thin film, a semiconductor such as silicon is used for the target 4 to be sputtered. For target 4, if necessary,
It is doped with p-type or n-type impurities. Chamber 1
When a rare gas is introduced into the chamber 1, and a direct current voltage, a high frequency voltage, or a high frequency voltage in which the direct current voltage is superimposed is applied to the electrode 2 by the plasma generating power source 7, a rare gas plasma is generated inside the chamber 1. To do. The target 4 is sputtered by the plasma, and an amorphous semiconductor thin film is formed on the substrate 5.

During the sputtering, a substrate bias is applied to the substrate 5 by the plasma generating power source 8, and the concentration of the rare gas contained in the amorphous semiconductor thin film is reduced by the application of the substrate bias. When the substrate bias is applied to the substrate 5, the surface of the substrate 5 is irradiated with rare gas ions having appropriate energy. By the irradiation of the rare gas ions, the rare gas remaining weakly bonded to the surface of the amorphous semiconductor thin film being formed on the substrate 5 is desorbed into the gas phase, and the formed amorphous semiconductor is formed. The concentration of the rare gas contained in the thin film is reduced. The substrate bias is adjusted so that the rare gas concentration of the amorphous semiconductor thin film is less than 1 × 10 ²⁰ cm ⁻³ . By adjusting the substrate bias appropriately, the rare gas concentration of the amorphous semiconductor thin film is set to 1 × 10 ²⁰ cm 2.
It is actually possible to suppress it to less than ^-3 .

The target 4 is formed by forming the silicon oxide thin film.
By a normal sputtering method in which sputtering is performed using silicon oxide as the material, or a reactive sputtering method in which silicon is used as the target 4 and sputtering is performed using a mixed gas of a rare gas and an oxygen gas as the sputtering gas. Is also feasible. The formed silicon oxide film is amorphous. Similar to the formation of the amorphous semiconductor thin film, the substrate bias is applied to the substrate 5 by the plasma generation power source 8 during the sputtering. By applying the substrate bias, the concentration of the rare gas contained in the silicon oxide thin film is reduced. Substrate bias, rare gas concentration in the silicon oxide film 5 × 10 ²¹ cm ^- is adjusted to be less than ^3. By adjusting the substrate bias appropriately, the rare gas concentration of the silicon oxide thin film is set to 5 × 10 ^21.
It is actually possible to suppress it to less than cm ⁻³ .

The target 4 is formed by forming the silicon nitride thin film.
A normal sputtering method in which sputtering is performed by using silicon nitride as a substrate, or a reactive sputtering method in which silicon is used as a target 4 and sputtering is performed by using a mixed gas of a rare gas and a nitrogen gas as a sputtering gas. Is also feasible. The formed silicon nitride film is amorphous. Similar to the formation of the silicon oxide thin film, a substrate bias is applied to the substrate 5 by the plasma generating power source 8 during the sputtering. By applying the substrate bias, the concentration of the rare gas contained in the silicon nitride thin film is reduced. Substrate bias, the rare gas concentration in the silicon nitride film is 5 × 10 ²¹ cm ^- is adjusted to be less than ^3. By adjusting the substrate bias appropriately, the rare gas concentration of the silicon nitride thin film is adjusted to 5 × 10 ^21.
It is actually possible to suppress it to less than cm ⁻³ .

The silicon oxynitride thin film is formed by the usual sputtering method in which silicon oxynitride is used as the target 4 and silicon is used as the target 4.
Further, it can be carried out by any of the reactive sputtering method in which sputtering is performed using a mixed gas of a rare gas, an oxygen gas and a nitrogen gas as a sputtering gas. The formed silicon oxynitride film is amorphous. Similar to the formation of the silicon oxide thin film and the silicon nitride thin film, the substrate bias is applied to the substrate 5 by the plasma generation power source 8 during the sputtering. By applying the substrate bias, the concentration of the rare gas contained in the silicon oxynitride thin film is reduced. The substrate bias is adjusted so that the concentration of the rare gas contained in the silicon oxynitride thin film is less than 5 × 10 ²¹ cm ⁻³ . By adjusting the substrate bias appropriately, the rare gas concentration of the silicon oxynitride thin film is set to 5 × 10 ²¹ cm ^−3.
It is actually possible to suppress it to less than.

As shown in FIG. 2, the addition of the grounded intermediate electrode 9 to the sputtering apparatus 10 means that the thin film can be formed in any of the amorphous semiconductor thin film and the insulator thin film. It is preferable in that the concentration of the rare gas therein is reduced. The intermediate electrode 9 is provided with an opening, and a mesh-shaped electrode is typically used for the intermediate electrode 9. Due to the insertion of the intermediate electrode 9, a rare gas plasma is generated mainly between the electrode 2 and the intermediate electrode 9, and the plasma density of the space between the electrode 3 holding the substrate 5 and the intermediate electrode 9 decreases. As a result, the rare gas concentration in the thin film formed on the substrate 5 is reduced. At this time, the substrate bias is applied to the substrate 5 by the plasma generation power source 8 during the sputtering, whereby the concentration of the rare gas in the thin film can be further reduced.

In order to further reduce the concentration of the rare gas,
In both the amorphous semiconductor thin film and the insulator thin film, the rare gas used for sputtering preferably contains helium. Helium, which has a small atomic weight, is easily desorbed in the gas phase by irradiation with rare gas ions.
Therefore, by containing helium in the rare gas used for sputtering, the amorphous semiconductor thin film formed,
It is possible to reduce the concentration of the residual rare gas in both the formation of the insulating thin film and the formation of the insulating thin film.

At this time, it is preferable that argon is contained in addition to helium in order to secure a film forming rate.
When helium is contained in the rare gas, the film forming rate is reduced. Since the rare gas contains argon having a high sputtering rate, the required film formation rate can be secured.

A semiconductor device including a thin film transistor is preferably manufactured by using the above-described thin film manufacturing method. FIG. 3 shows a thin film transistor manufacturing method performed by using the above-described thin film manufacturing method.

As shown in FIG. 3A, an insulating film 12 for protecting the substrate 11 is formed on the insulating substrate 11. The insulating film 12 is formed of a silicon oxide thin film, a silicon nitride thin film, or a silicon oxynitride thin film. The insulating film 12 is formed by the above-described method for forming a silicon oxide thin film, a silicon nitride thin film, or a silicon oxynitride thin film, and the concentration of the rare gas contained in the insulating film 12 is 5 × 1.
It is suppressed to less than 0 ²¹ cm ⁻³ .

Subsequently, the amorphous semiconductor thin film 13 is formed on the insulating film 12. The amorphous semiconductor thin film 13 is formed by the above-described method for forming an amorphous semiconductor thin film, and the concentration of the rare gas contained in the amorphous semiconductor thin film 13 is 1 × 10 5.
It is suppressed to less than ²⁰ cm ⁻³ . At this time, the target 4 of the sputtering apparatus 10 is doped with p-type or n-type impurities as needed. It is possible to form the intrinsic, p-type, and n-type conductive type amorphous semiconductor thin film 13.

Subsequently, as shown in FIG. 3B, after the amorphous semiconductor thin film 13 is patterned, a photoresist 14 is formed on the amorphous semiconductor thin film 13 by a photolithography technique. It Amorphous semiconductor thin film 13 using the formed photoresist 14 as a mask
Impurities 15 are doped in. By doping with the impurity 15, the amorphous semiconductor thin film 13 is formed with impurity-doped regions 16 and 17 doped with the impurity 15.

Subsequently, as shown in FIG. 3C, after the photoresist 14 is removed, the laser light 18 generated by the excimer laser is irradiated from the upper surface side of the substrate 11. The laser light 18 is ultraviolet light. The laser light 18, which is ultraviolet light, is absorbed by the amorphous semiconductor thin film 13, and the amorphous semiconductor thin film 13 is locally heated. By heating the amorphous semiconductor thin film 13, the amorphous semiconductor thin film 1
3 is polycrystallized to form a polycrystal semiconductor thin film 19. Further, the irradiation of the laser beam 18 activates the impurities doped in the impurity-doped regions 16 and 17, and the source region 20 and the drain region 21 are formed in the polycrystalline semiconductor thin film 19.

The concentration of the rare gas in the amorphous semiconductor thin film 13 is
The suppression to less than 1 × 10 ²⁰ cm ⁻³ effectively prevents film peeling of the amorphous semiconductor thin film 13 during irradiation with the laser beam 18. The suppression of the concentration of the rare gas in the amorphous semiconductor thin film 13 reduces the amount of the rare gas released from the amorphous semiconductor thin film 13 during the irradiation of the laser beam 18, and thus the film peeling of the amorphous semiconductor thin film 13 is prevented. To prevent.

Further, the concentration of the rare gas in the insulating film 12 is 5 ×.
The suppression of less than 10 ²¹ cm ⁻³ effectively prevents film peeling of the insulating film 12 during the irradiation of the laser beam 18. By the irradiation of the laser light 18, the insulating film 12 is heated directly by the absorption of the laser light 18 or indirectly by the temperature rise of the amorphous semiconductor thin film 13. The suppression of the concentration of the rare gas in the insulating film 12 reduces the amount of the rare gas released from the insulating film 12 during the irradiation with the laser light 18,
The film peeling of the insulating film 12 is prevented. However, the insulating film 12
Has a low absorptance of the laser light 18, which is ultraviolet light, and therefore the temperature rise during the irradiation of the laser light 18 is not so remarkable as that of the amorphous semiconductor thin film 13. Therefore, the concentration of the rare gas in the insulating film 12 does not necessarily need to be less than 1 × 10 ²⁰ cm ⁻³ . The concentration of the rare gas in the insulating film 12 is 1 ×
It may be preferable to set it to 10 ²⁰ cm ⁻³ or more and less than 5 × 10 ²¹ cm ^{−3 in} order to facilitate adjustment of the substrate bias applied when forming the insulating film 12.

Subsequently, as shown in FIG. 3D, a gate insulating film 22 covering the polycrystalline semiconductor thin film 19 is formed.
After the formation of the gate electrode 2, the gate electrode 2 is formed on the gate insulating film 22.
3 is formed. After forming the gate electrode 23, the substrate 11
Is exposed to a hydrogen plasma atmosphere. Hydrogen contained in the hydrogen plasma atmosphere terminates dangling bonds contained in the polycrystalline semiconductor thin film 19 and reduces defects in the polycrystalline semiconductor thin film 19.

Subsequently, as shown in FIG. 3E, after the interlayer insulating film 24 is formed, the source region 20,
Contact holes 25 and 26 reaching the drain region 21 are formed. Further, the source electrode 27 and the drain electrode 28 respectively connected to the source region 20 and the drain region 21 are formed, and the structure of the thin film transistor is completed.

The laser light sufficiently weaker than the laser light 18 is applied to the entire formed thin film transistor to perform the laser annealing. This means that the characteristics of the interface between the polycrystalline semiconductor thin film 19 and the gate insulating film 22 are characteristic. It is suitable for improving the above and obtaining a high performance thin film transistor. in this case,
The gate insulating film 22 and the interlayer insulating film 24 are formed by the above-described method for forming the silicon oxide thin film, the silicon nitride thin film, and the silicon oxynitride thin film, because the gate insulating film 22 and the interlayer insulating film 24 are formed by laser annealing. It is suitable for preventing film peeling. However, the thin film forming the thin film transistor does not reach a high temperature in the laser annealing after the structure of the thin film transistor is formed. Therefore, the gate insulating film 22 and the interlayer insulating film 24 do not necessarily have to be formed by the method for forming the silicon oxide thin film, the silicon nitride thin film, and the silicon oxynitride thin film described above. The gate insulating film 22 and the interlayer insulating film 24 can also be formed by a plasma CVD method.

As described above, in the present embodiment, the concentration of the rare gas in the amorphous semiconductor thin film 13 is 1 × 10.
^It is suppressed to less than ²⁰ cm ^−3, and the film peeling of the amorphous semiconductor thin film 13 during the irradiation of the laser beam 18 is effectively prevented.

Further, the concentration of the rare gas in the insulating film 12 is 5 ×.
It is suppressed to less than 10 ²¹ cm ⁻³ , and film peeling of the insulating film 12 during the irradiation of the laser beam 18 is effectively prevented.

(Second Embodiment) In the second embodiment,
Ion plating is used to form the thin film. FIG. 4 shows an ion plating device 30 used in the second embodiment. The ion plating device 30 is
It has a configuration for performing the high frequency method among the ion plating methods. The ion plating device 30 includes a chamber 31. A crucible 32 is provided inside the chamber 31. The crucible 32 contains a thin film forming material 33. A heater 34 that heats the crucible 32 is provided near the crucible 32. Heater 34
Is connected to the power supply 35. The power source 35 is a crucible 3.
Electric power for heating 2 is supplied to the heater 34.

An electrode 36 is provided inside the chamber 31 so as to face the crucible 32. The electrode 36 holds a substrate 37 on which a thin film is formed. The electrode 36 is a DC power source 3
8 is connected. The DC power supply 38 applies a negative substrate bias voltage to the substrate 37 via the electrode 36.

An RF coil 39 is provided between the electrode 36 and the crucible 32. The RF coil 39 is connected to the high frequency power supply 40. The high frequency power supply 40 applies a high frequency voltage to the RF coil 39.

Noble gas, oxygen gas,
Also, a piping system for introducing nitrogen gas and an exhaust pump system for decompressing the chamber 31 are connected. However, the piping system and the exhaust pump system are not shown. Chamber 31
Examples of the rare gas introduced into the are helium, argon, neon, krypton, and xenon. Oxygen gas,
The nitrogen gas and the nitrogen gas are introduced into the chamber 31 as necessary, and when the oxide, the nitride, and the oxynitride are not formed, the oxygen gas and the nitrogen gas are not introduced into the chamber 31.

When an amorphous semiconductor thin film is formed by the ion plating device 30 described above, a semiconductor such as silicon is used as the material 33 put in the crucible 32. The material 33 is doped with p-type or n-type impurities as needed. When a rare gas is introduced into the chamber 31 and a high frequency voltage is applied to the RF coil 39 by the high frequency power supply 40, a rare gas plasma is generated inside the chamber 31. At the same time, the crucible 32
It is heated by the heater 34 and the material 33 evaporates. The evaporated material 33 is ionized by the plasma generated inside the chamber 31 and is charged. The charged material 33 is attracted to the substrate 37 by the negative substrate bias voltage applied to the substrate 37,
In this, an amorphous semiconductor thin film is formed.

At this time, by appropriately adjusting the negative substrate bias voltage applied to the substrate 37, the rare gas concentration of the amorphous semiconductor thin film is suppressed to less than 1 × 10 ²⁰ cm ⁻³ . Appropriate adjustment of the substrate bias voltage is done by the substrate 37
To control the balance between the deposition rate of the amorphous semiconductor thin film and the re-sputtering rate of the amorphous semiconductor thin film, and irradiate the growing amorphous semiconductor thin film with ions having appropriate energy. To enable. Furthermore, proper adjustment of the substrate bias voltage keeps the ionization degree of the material 33 below that of the rare gas in the plasma. By these actions, the rare gas concentration of the amorphous semiconductor thin film is set to 1 × 10.
It is possible to suppress it to less than ²⁰ cm ⁻³ .

When a silicon oxide thin film is formed, silicon is put in the crucible 32 as a material 33, and oxygen gas is introduced into the chamber 31 in addition to the rare gas.

Similarly, when a silicon nitride thin film is formed, silicon is put in the crucible 32 as the material 33, and nitrogen gas is introduced into the chamber 31 in addition to the rare gas.

Further, when a silicon oxynitride thin film is formed, silicon is put in the crucible 32 as the material 33, and oxygen gas and nitrogen gas are introduced into the chamber 31 in addition to the rare gas. It

In forming any of the silicon oxide thin film, the silicon nitride thin film, and the silicon oxynitride thin film, the negative substrate bias voltage applied to the substrate 37 is appropriately adjusted as in the formation of the amorphous semiconductor thin film. By doing so, the rare gas concentration in the formed thin film can be less than 5 × 10 ²¹ cm ⁻³ .

As shown in FIG. 5, the RF coil 3
Inserting the grounded intermediate electrode 41 between the electrode 9 and the electrode 36 is effective in reducing the rare gas concentration in the formed thin film. An opening is provided in the intermediate electrode 41, and as the intermediate electrode 41, a mesh electrode is typically used. By inserting the intermediate electrode 41, plasma of a rare gas is generated mainly between the RF coil 39 and the intermediate electrode 41, and the plasma density in the space between the electrode 36 holding the substrate 37 and the intermediate electrode 41 decreases. . As a result, the rare gas concentration in the thin film formed on the substrate 37 is reduced.

The thin film manufacturing method described above can be preferably used for manufacturing the thin film transistor described in the first embodiment.

In the following, detailed examples of the first embodiment described above will be described.

(Example 1) In Example 1, an amorphous silicon thin film was formed by the sputtering apparatus 10 shown in FIG.

Conditions for forming the amorphous silicon thin film are as follows:
It is as follows. Intrinsic silicon was used as the material of the target 4. The sizes of the electrode 2 and the target 4 were 60 × 70 cm and 50 × 60 cm, respectively. Argon gas has a flow rate of 10 sccc in the chamber 1.
The pressure in the chamber 1 was adjusted to 0.1 Pa. A high frequency power of 13.56 Mhz and 1 kW is supplied to the electrode 2 by the plasma generation power supply 7, and a 13.56 M high frequency power is supplied to the electrode 3 by the plasma generation power supply 8.
High frequency power of 0.3 kW was applied for hz. The temperature of the substrate 5 was adjusted to 130 ° C. by the heater 6.

Under these conditions, an amorphous silicon thin film was formed on the substrate 5. SIMS (Secondary Ion
As a result of measuring the concentration of argon contained in the formed amorphous silicon thin film by Mass Spectrometry, the argon concentration of the amorphous silicon thin film is 1 ×.
It was less than 10 ²⁰ cm ⁻³ .

Similar experiments were carried out using helium gas instead of argon gas. The helium concentration of the amorphous silicon thin film was less than 1 × 10 ¹⁹ cm ⁻³ . This result indicates that the concentration of the rare gas contained in the amorphous silicon thin film can be further reduced by using helium gas as the sputtering gas. However, the use of helium gas reduced the growth rate of the amorphous silicon thin film to 1/5.

Similar experiments were carried out using a mixed gas of argon gas and helium gas instead of argon gas. A film formation rate that is half that in the case where the sputtering gas is only argon was obtained, and the concentration of the rare gas contained in the amorphous silicon thin film was lower than that when the sputtering gas was only argon.

Example 2 In Example 2, an amorphous silicon thin film was formed by the sputtering apparatus 10 shown in FIG.

The conditions for forming the amorphous silicon thin film are as follows. As the material of the target 4, silicon doped with boron was used. The doping concentration of boron was 5 × 10 ¹⁷ cm ⁻³ . The size of the electrode 2 and the target 4 is 60 × 70, respectively.
cm and 50 × 60 cm. Argon gas was introduced into the chamber 1 at a flow rate of 10 sccm, and the pressure in the chamber 1 was adjusted to 0.1 Pa. The electrode 2 is supplied with a DC power of 2 kW by the plasma generating power supply 7, and the electrode 3 is supplied with 1 kW by the plasma generating power supply 8.
A power of 3.56 Mhz, 0.3 kW was applied. The temperature of the substrate 5 was adjusted to 130 ° C. by the heater 6.

Under these conditions, the substrate 5 is amorphous.
A silicon thin film was formed. Formed by SIMS
Concentration of argon contained in the amorphous silicon thin film
As a result, the amorphous silicon thin film
Concentration is 1 × 10²⁰cm ^-3Was less than.

As in Example 1, the use of helium gas as the sputtering gas reduced the concentration of noble gas contained in the amorphous silicon thin film. Furthermore, the use of a mixed gas of argon gas and helium gas as the sputtering gas also reduced the concentration of the rare gas contained in the amorphous silicon thin film.

Further, similar results were obtained when the target 4 was doped with phosphorus instead of boron.

Example 3 In Example 3, a silicon oxide thin film was formed by the sputtering apparatus 10 shown in FIG.

The conditions for forming the silicon oxide thin film are as follows. Silicon oxide was used as the material of the target 4. The sizes of the electrode 2 and the target 4 were 60 × 70 cm and 50 × 60 cm, respectively. Argon gas at a flow rate of 10 sccm is contained in the chamber 1.
Oxygen gas was introduced at a flow rate of 0 sccm. The pressure in the chamber 1 was adjusted to 0.2 Pa. The electrode 2 is supplied with a plasma generating power source 7 at 13.56 MHz, 1.
High-frequency power of 0 kW is supplied, and the electrode 3 is supplied with a plasma generating power source 8 at 13.56 Mhz, 0.3 kW.
Power was applied. The temperature of the substrate 5 was adjusted to 130 ° C. by the heater 6.

Under these conditions, a silicon oxide thin film was formed on the substrate 5. SIMS (Secondary Ion Mass Spe
As a result of measuring the concentration of argon contained in the silicon oxide thin film formed by ctrometry), the argon concentration of the silicon oxide thin film was less than 5 × 10 ²¹ cm ⁻³ .

As in Examples 1 and 2, the use of helium gas as the sputtering gas reduced the concentration of the rare gas contained in the silicon oxide thin film. The rare gas concentration (ie, helium concentration) contained in the silicon oxide thin film is 1 ×
It was reduced to 10 ²¹ cm ⁻³ .

Furthermore, the use of a mixed gas of argon gas and helium gas as the sputtering gas also reduced the concentration of the rare gas contained in the silicon oxide thin film.
The rare gas concentration contained in the silicon oxide thin film is 3 × 10.
It was reduced to ²¹ cm ⁻³ .

(Example 4) In Example 4, a silicon nitride thin film was formed by the sputtering apparatus 10 of FIG. 2 in which the intermediate electrode 9 was inserted.

The conditions for forming the silicon nitride thin film are as follows. Silicon nitride was used as the material of the target 4. The sizes of the electrode 2 and the target 4 were 60 × 70 cm and 50 × 60 cm, respectively. Argon gas was supplied to the chamber 1 at a flow rate of 10 sccm.
Nitrogen gas was introduced at a flow rate of 10 sccm. The pressure in the chamber 1 was adjusted to 0.2 Pa. The electrode 2 has
With the plasma generating power source 7, 13.56 MHz,
High-frequency power of 2.0 kW is supplied to the electrode 3 by the plasma generation power source 8 at 13.56 Mhz, 0.3
Power of kW was applied. The temperature of the substrate 5 was adjusted to 130 ° C. by the heater 6. The intermediate electrode 9 was grounded.

In Example 4, a higher high frequency power is applied to the electrode 2 than in Example 3. This is because formation of a silicon nitride thin film requires more activation energy than formation of a silicon oxide thin film. In Example 4,
A relatively high high frequency power is applied to the electrode 2, and plasma having a high argon ion density is generated in the chamber 1.

At this time, the presence of the intermediate electrode 9 suppresses the argon ion density near the surface of the substrate 5 to a low level, and reduces the argon concentration of the formed silicon nitride thin film. Due to the presence of the intermediate electrode 9, plasma generation is localized between the electrode 2 and the intermediate electrode 9, and the argon ion density near the surface of the substrate 5 is suppressed to be low. Thereby, the argon concentration of the formed silicon nitride thin film is reduced. The insertion of the intermediate electrode 9 is particularly effective for forming a silicon nitride thin film which is suitable for inputting high-frequency power. However, when the high frequency power supplied to the electrode 2 is low, the sputtering apparatus 10 of FIG. 1 without the intermediate electrode 9 can be used.

The silicon nitride thin film formed under these conditions was analyzed by SIMS. The SIMS analysis shows that the silicon nitride thin film has an argon concentration of 5 × 10 5.
It was clarified to be less than ²¹ cm ⁻³ .

As in Example 3, the use of helium gas as the sputtering gas reduced the concentration of the rare gas contained in the silicon nitride thin film. The rare gas concentration (ie, helium concentration) contained in the silicon nitride thin film is 1 × 10.
It was reduced to ²¹ cm ⁻³ .

Furthermore, the use of a mixed gas of argon gas and helium gas as the sputtering gas also reduced the concentration of the rare gas contained in the silicon nitride thin film.
The rare gas concentration contained in the silicon nitride thin film is 3 × 10 5.
It was reduced to ²¹ cm ⁻³ .

(Example 5) In Example 5, a silicon nitride thin film was formed by the sputtering apparatus 10 of FIG. 2 in which the intermediate electrode 9 was inserted.

The conditions for forming the silicon oxynitride thin film are as follows. Silicon oxide was used as the material of the target 4. The sizes of the electrode 2 and the target 4 were 60 × 70 cm and 50 × 60 cm, respectively. Argon gas was supplied to the chamber 1 at a flow rate of 10 sccm.
Nitrogen gas was introduced at a flow rate of 10 sccm. Oxygen gas can be further introduced into the chamber 1. The pressure in the chamber 1 was adjusted to 0.2 Pa.
13.5 is applied to the electrode 2 by the plasma generating power source 7.
High frequency power of 6MHz and 2.0kW is supplied to the electrode 3
The plasma generation power source 8 to 13.56Mh
Power of 0.3 kW was applied. The temperature of the substrate 5 is
The temperature was adjusted to 130 ° C. by the heater 6. The intermediate electrode 9 is
Grounded.

In Example 5, as in Example 4, the electrode 2
A relatively high high frequency power is applied to. This is because the formation of the silicon oxynitride thin film requires more activation energy than the formation of the silicon oxide thin film. In Example 5, a relatively high high frequency power is applied to the electrode 2 and plasma having a high argon ion density is generated in the chamber 1.

At this time, the presence of the intermediate electrode 9 is the same as in Example 4.
Similarly, the argon ion density near the surface of the substrate 5 is suppressed to be low, and the argon concentration of the formed silicon oxynitride thin film is reduced. The insertion of the intermediate electrode 9 is particularly effective for forming a silicon oxynitride thin film which is suitable for inputting high-frequency power. However, when the high frequency power supplied to the electrode 2 is low, the sputtering apparatus 10 of FIG. 1 without the intermediate electrode 9 can be used.

The silicon oxynitride thin film formed under these conditions was analyzed by SIMS. The SIMS analysis shows that the silicon oxynitride thin film has an argon concentration of 5 × 1.
It was clarified that it was less than 0 ^{2 1} cm ^-3 .

As in Example 3, the use of helium gas as the sputtering gas reduced the concentration of noble gas contained in the silicon oxynitride thin film. The rare gas concentration (ie, helium concentration) contained in the silicon oxynitride thin film is 1 ×
It was reduced to 10 ²¹ cm ⁻³ .

Furthermore, the use of a mixed gas of argon gas and helium gas as the sputtering gas also reduced the concentration of the rare gas contained in the silicon oxynitride thin film. The concentration of rare gas contained in the silicon oxynitride thin film is 3 ×
It was reduced to 10 ²¹ cm ⁻³ .

(Example 6) In Example 6, a thin film transistor was manufactured by the thin film transistor manufacturing method of the first embodiment.

Referring to FIG. 3A, the insulating substrate 11
As a glass substrate or a plastic substrate was used. A silicon oxide thin film having a film thickness of 500 nm was formed as the insulating film 12 on the substrate 11. The silicon oxide thin film is formed under the same conditions as in Example 3, and the silicon oxide thin film has an argon concentration of about 1 × 10 ²¹ cm ^−.
It was suppressed to ³ . Subsequently, an amorphous silicon thin film having a film thickness of 50 nm was formed as the amorphous semiconductor thin film 13. The amorphous silicon thin film was formed under the same conditions as in Example 1. As the target 4, a silicon target made of intrinsic silicon was used. The argon concentration of the silicon amorphous silicon thin film was suppressed to about 8 × 10 ¹⁹ cm ⁻³ .

After the amorphous semiconductor thin film 13 was patterned, a photoresist 14 was formed by photolithography, as shown in FIG. 3 (b). Then, the impurity 15 was introduced into the amorphous semiconductor thin film 13.
The introduction of the impurity 15 was performed by exposing the substrate 11 to phosphine (PH ₃ ) plasma or diborane (B ₂ H ₆ ) plasma using the photoresist 14 as a mask.
When forming an N-channel thin film transistor, the substrate 11 was exposed to phosphine plasma. The amorphous semiconductor thin film 13 is doped with phosphorus as the impurity 15 by the phosphine plasma treatment,
17 was formed. The doping amount of phosphorus is 10 ²⁰ -10
It was ²¹ cm ⁻³ . The doping amount of phosphorus was controlled by the acceleration voltage for extracting ions from the plasma to the substrate and the plasma density. When forming a P-channel thin film transistor, the substrate 9 was exposed to diborane plasma. The amorphous semiconductor thin film 13 was doped with boron as the impurity 15 by the diborane plasma treatment.

Subsequently, as shown in FIG. 3C, after removing the photoresist 14, the laser beam 18 was irradiated from the upper surface side of the substrate 11. The laser light 18 was generated by an excimer laser containing xenon (Xe) and chlorine (Cl). The energy density of the laser light 18 is 40
It was 0 mJ / cm ² . By irradiating the laser light 18,
The amorphous semiconductor thin film 13 was crystallized to form a polycrystalline semiconductor thin film 19 of polycrystalline silicon. Furthermore, laser light 1
By the irradiation of 8 the phosphorus (or boron) in the impurity-doped regions 16 and 17 is activated, and the source region 2
0, the drain region 21 was formed. The crystal grain size of the polycrystalline silicon was 100 nm or more, and the resistivity of the source region 20 and the drain region 21 was 5 × 10 ⁻³ Ωcm or less.

Irradiation with the laser beam 18 did not cause film peeling of the insulating film 12, the amorphous semiconductor thin film 13, and the polycrystalline semiconductor thin film 19. This is because the insulating film 12 has an argon concentration of about 1 × 10 ²¹ cm ⁻³ and the amorphous semiconductor thin film 1
This is because the argon concentration of ³ was suppressed to about 8 × 10 ¹⁹ cm ⁻³ .

Subsequently, as shown in FIG. 3D, a gate insulating film 22 covering the polycrystalline semiconductor thin film 19 is formed.
As a result, a silicon oxide thin film having a film thickness of 70 nm was formed. The silicon oxide thin film was formed under the same conditions as in Example 3, and the gate insulating film 22 having a low argon concentration was formed.

The gate electrode 21 is formed on the gate insulating film 22 with a metal such as aluminum or tungsten.
Was formed.

Further, the substrate 11 was exposed to a hydrogen plasma atmosphere. The hydrogen contained in the hydrogen plasma terminated the dangling bonds contained in the polycrystalline silicon forming the polycrystalline semiconductor thin film 19, and the defect density of the polycrystalline silicon was reduced. In order to improve the characteristics of the thin film transistor, it is preferable that the hydrogen plasma has a high plasma density, specifically, 10 ¹⁰ cm ⁻³ or more. Hydrogen plasma having a high plasma density can be generated by an inductively coupled plasma source or a microwave plasma source.

Subsequently, as shown in FIG. 3E, a silicon oxide thin film was formed as the interlayer insulating film 24. The silicon oxide thin film was formed under the same conditions as those described in Example 3.

After forming the contact holes 25 and 26,
The source electrode 27 and the drain electrode 28 were formed of a metal such as aluminum or tungsten, and the structure of the thin film transistor was completed.

Further, laser light having an energy density of about 100 mJ / cm ² generated by an excimer laser was applied to the entire structure of the thin film transistor, and weak laser annealing was performed. This weak laser annealing improves the interface characteristics between the polycrystalline semiconductor thin film 19 and the gate insulating film 22 and improves the characteristics of the thin film transistor. At this time, the insulating film 12, the polycrystalline semiconductor thin film 19, the gate insulating film 22, and the interlayer insulating film 24 all had a low argon concentration, and film peeling due to weak laser annealing did not occur.

N-channel thin film completed by the above steps
Transistor mobility is 50 cm ^TwoV^-1s^-1that's all
And the threshold voltage was 2 V or less. Furthermore, p
The mobility of the channel thin film transistor is 40 cm^TwoV
^-1s^-1And above, the threshold voltage is -2V or more
there were.

In Example 6, the threshold voltage tended to shift to the negative side depending on the irradiation condition of the laser beam 18. This is because, in the polycrystalline semiconductor thin film 19,
The part that constitutes the channel region of the thin film transistor is
It is caused by the fact that it is formed of intrinsic polycrystalline silicon, and due to the level in the energy gap of the polycrystalline silicon, it is made a little n-type.

The shift of the threshold voltage to the negative side is
1 × 10 ¹⁷ −1 × 10 on the silicon target 4
It can be solved by doping a very small amount of boron of about ¹⁸ cm ⁻³ . By doping the target 4 with boron, the polycrystalline semiconductor thin film 19 is doped with boron, and a thin film transistor having a normal threshold voltage can be formed.

The shift of the threshold voltage to the negative side can also be eliminated by introducing a small amount of diborane gas into the chamber 1 during the formation of the amorphous semiconductor thin film 13 by sputtering. The amount of diborane gas added is
It is typically a few ppb. By introducing diborane gas into the chamber 1, the polycrystalline semiconductor thin film 19 is doped with boron, and a thin film transistor having a normal threshold voltage can be formed.

In the sixth embodiment, the gate insulating film 22 and the interlayer insulating film 24 are formed by the sputtering method, but the gate insulating film 22 and the interlayer insulating film 24 are formed of silane gas, oxygen gas, and dinitrogen oxide (N). It can also be formed by a plasma CVD method using a mixed gas of ₂ O) gas. The process after irradiation with the laser light 18 does not include a high temperature process, and the formation of the gate insulating film 22 and the interlayer insulating film 24 by the plasma CVD method does not cause a big problem such as film peeling.

[0126]

The present invention provides a technique for further suppressing the occurrence of film peeling in a semiconductor process.

The present invention also provides a technique for suppressing the occurrence of film peeling of the semiconductor thin film in the semiconductor process, particularly in the manufacturing process of the thin film transistor.

The present invention also provides a technique for suppressing the occurrence of film peeling of the insulator thin film in the semiconductor process, particularly in the manufacturing process of the thin film transistor.

[0129]

[Brief description of drawings]

FIG. 1 shows a sputtering apparatus used in a first embodiment of a thin film manufacturing method according to the present invention.

FIG. 2 shows another sputtering apparatus used in the first embodiment of the thin film manufacturing method according to the present invention.

FIG. 3 shows a method of manufacturing a thin film transistor using the first embodiment of the method of manufacturing a thin film according to the present invention.

FIG. 4 shows an ion plantation apparatus used in a second embodiment of the thin film manufacturing method according to the present invention.

FIG. 5 shows another ion plantation apparatus used in the second embodiment of the method for producing a thin film according to the present invention.

[Explanation of symbols]

1: Chamber 2, 3: Electrode 4: Target 5: substrate 6: heater 7, 8: Power supply for plasma generation 9: Intermediate electrode 10: Sputtering device 11: substrate 12: Insulating film 13: Amorphous semiconductor thin film 14: Photoresist 15: Impurity 16, 17: impurity-doped region 18: Laser light 19: Polycrystalline semiconductor thin film 20: Source area 21: Drain region 22: Gate insulating film 23: Gate electrode 24: Interlayer insulating film 25, 26: Contact hole 27: Source electrode 28: Drain electrode 30: Ion plating device 31: Chamber 32: Crucible 33: Material 34: heater 35: Power supply 36: Electrode 37: substrate 38: DC power supply 39: RF coil 40: High frequency power supply 41: Intermediate electrode

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/316 H01L 21/316 Y 21/336 29/78 618G 29/786 618A 627G 626C F term (reference) 4K029 BA35 BA46 BA58 BB10 BC05 BD01 CA03 CA05 CA13 EA05 GA01 5F052 AA02 BB07 DA01 DA02 DA03 DB07 DB10 EA16 HA07 JA01 5F058 BA10 BC02 BC08 BC11 BF12 BF18 BF38 DDFDD DD01 DD30A01 DD03 DD03A02 DD15 DD03A01A02 DD16 GG02 EE04 FF02 FF28 FF30 GG02 GG13 GG16 GG25 GG32 GG33 GG34 GG35 GG42 GG43 HJ01 HJ04 HJ18 HJ23 HL03 HL04 NN02 NN23 NN34 NN35 PP03 PP27 QQ11 QQ25 QQ30

Claims (29)

[Claims] 1. A PVD (Physical Vapor) using a rare gas.
Deposition) method for forming an amorphous semiconductor thin film on the substrate by a method, wherein the concentration of the rare gas contained in the amorphous semiconductor thin film,
A method for producing a thin film having a ^{thickness of} less than 1 × 10 ²⁰ cm ⁻³ . 2. The thin film manufacturing method, wherein the forming step includes a step of positively decreasing the concentration during the formation of the amorphous semiconductor thin film. 3. The thin film manufacturing method according to claim 1, wherein the amorphous semiconductor thin film contains silicon as a main component. 4. The thin film manufacturing method according to claim 1, wherein the forming step includes a sputtering step of forming the amorphous semiconductor thin film by a sputtering method. 5. The thin film manufacturing method according to claim 4, wherein the sputtering step includes a step of applying a substrate bias to the substrate. 6. The step of generating a plasma of the rare gas by applying a voltage between a first electrode connected to a target made of a semiconductor material and a second electrode in the sputtering step. A step of holding the substrate in a space other than the plasma generation space between the first electrode and the second electrode, and forming the amorphous semiconductor thin film on the substrate by sputtering the target with the plasma The method for producing a thin film according to claim 4, further comprising: 7. The thin film manufacturing method according to claim 1, wherein the forming step includes a step of forming the amorphous semiconductor thin film by an ion plating method. 8. A laser annealing step of forming a polycrystalline semiconductor thin film by irradiating the amorphous semiconductor thin film with laser light to anneal the amorphous semiconductor thin film after forming the amorphous semiconductor thin film. The method for producing a thin film as described in. 9. The rare gas contains helium.
The method for producing a thin film as described in. 10. The method of manufacturing a thin film according to claim 1, wherein the rare gas contains helium and argon. 11. PVD (Physical Vap) using rare gas
or Deposition) method to form an insulator thin film on a substrate by an insulator thin film forming step, wherein the concentration of the rare gas contained in the insulator thin film is 5 × 1.
A method for producing a thin film having a ^{thickness of} less than 0 ²¹ cm ⁻³ . 12. The thin film manufacturing method according to claim 11, wherein the insulating thin film forming step includes a step of positively reducing the concentration during the formation of the insulating thin film. 13. The thin film manufacturing method according to claim 11, wherein the insulator thin film is formed of one material selected from the group consisting of silicon oxide, silicon nitride, and silicon oxynitride. 14. The thin film manufacturing method according to claim 11, wherein the insulating thin film forming step includes a sputtering step of forming the insulating thin film by a sputtering method. 15. The thin film manufacturing method according to claim 14, wherein the sputtering step includes a step of applying a bias to the substrate. 16. The sputtering step comprises applying a voltage between a first electrode and a second electrode connected to a target formed of a material forming the insulator thin film, thereby applying the rare gas. A step of generating plasma; a step of holding the substrate in a space other than the plasma generation space between the first electrode and the second electrode; and a step of sputtering the target with the plasma to insulate the substrate. The thin film manufacturing method according to claim 14, further comprising the step of forming a body thin film. 17. The thin film manufacturing method according to claim 11, wherein the insulating thin film forming step includes a step of forming the insulating thin film by an ion plating method. 18. A first step of forming an insulator thin film on the upper surface side of a substrate by a first PVD method using a first rare gas, and a second step of forming an amorphous semiconductor thin film on the upper surface side of the insulator thin film. And a third step of polycrystallizing the amorphous semiconductor thin film by performing laser annealing of irradiating the amorphous semiconductor thin film with laser light, the first rare gas included in the insulator thin film. The concentration of 5
A method for manufacturing a semiconductor device having a ^{density of} less than × 10 ²¹ cm ⁻³ . 19. The method of manufacturing a semiconductor device according to claim 18, wherein the first PVD method is a sputtering method. 20. In the second step, a second rare gas is used.
The amorphous semiconductor thin film is formed by the second PVD method.
Of the second rare gas contained in the amorphous semiconductor thin film.
Concentration is 1 × 10²⁰cm ^-3In less than 18
A method for manufacturing a semiconductor device as described above. 21. An amorphous semiconductor thin film formed by a PVD method using a rare gas, wherein the concentration of the rare gas contained in the amorphous semiconductor thin film is less than 1 × 10 ²⁰ cm ⁻³ . 22. The amorphous semiconductor thin film according to claim 21, which is formed by a sputtering method using the rare gas as a sputtering gas. 23. The amorphous semiconductor thin film according to claim 21, which contains silicon as a main component. 24. A PVD method using a rare gas, wherein the concentration of the rare gas contained in the insulator thin film is
An insulator thin film having a ^{thickness of} less than 5 × 10 ²¹ cm ⁻³ . 25. The insulator thin film according to claim 24, which is formed by a sputtering method using the rare gas as a sputtering gas. 26. Formed in one of the group consisting of silicon oxide, silicon nitride, silicon oxynitride.
Insulator thin film according to. 27. A substrate and an insulating film formed on the upper surface side of the substrate, wherein the rare gas concentration in the insulating film is positively 5 ×.
A semiconductor device suppressed to less than 10 ²¹ cm ⁻³ . 28. The semiconductor device according to claim 27, further comprising a polycrystalline semiconductor thin film formed on the upper surface side of the insulating film. 29. The insulating film is formed of P using the rare gas.
29. The semiconductor device according to claim 28, which is formed by a VD method.