Method of manufacturing a semiconductor device

Abstract

This specification relates to a method for manufacturing a semiconductor device. A method for manufacturing a semiconductor device according to an embodiment may include a step of forming an insulating layer on a substrate, a step of performing a heat treatment process using microwaves, a step of forming a conductive layer on the insulating layer, and a step of performing a heat treatment process.

Description

Technical Field

[0001] This specification relates to a method for manufacturing a semiconductor device.

Background Art

[0002] As semiconductors are scaled down, the thickness of the gate insulating film becomes thinner than the limit, resulting in a problem of leakage current. To overcome such a problem, in the manufacturing process of semiconductor devices, substances with excellent insulating effects (e.g., SiO2) are widely used. In recent years, High-K (high dielectric constant) substances (e.g., HfO2, HfSi x , HfAl x ) are also used together as the active layer. Defects occur in the deposition process of these insulating substances and High-K substances. Therefore, the defects are cured by a heat treatment process. Therefore, with the development of technology in the semiconductor field, the importance of heat treatment process technology has been increasing.

[0003] However, when high-temperature heat treatment is performed in the manufacturing process of semiconductor devices, the possibility of generating ionized interface charges and trap charges increases, which may reduce the reliability of the semiconductor devices. Also, when high-temperature heat treatment is performed in the manufacturing process of semiconductor devices, the thermal budget may increase. Therefore, it is necessary to develop an efficient and economical heat treatment process applicable in the manufacturing process of semiconductor devices.

[0004] In a prior document (Republic of Korea Registered Patent Publication No. 10-0621776), a method of performing an annealing process on an amorphous silicon film for a short time and applying microwaves is disclosed. However, the prior document does not disclose a method for complementing the disadvantages of microwave heat treatment.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The object of the present specification is to provide a method for manufacturing a semiconductor device that can improve the reliability of the semiconductor device by complex heat treatment and improve electrical characteristics.

[0006] The object of the present specification is not limited to the objects mentioned above, and other objects and advantages of the present specification not mentioned can be more clearly understood from the examples of the present specification described below. Also, the objects and advantages of the present specification can be realized by the components described in the claims and combinations thereof.

Means for Solving the Problems

[0007] A method for manufacturing a semiconductor device according to an embodiment may include a step of forming an insulating layer on a substrate, a step of performing a microwave heat treatment process, a step of forming a conductive layer on the insulating layer, and a step of performing a heat treatment process.

[0008] A method for manufacturing a semiconductor device according to an embodiment may include a step of forming a first insulating layer on a substrate, a step of performing a first microwave heat treatment process, a step of forming a second insulating layer having a higher dielectric constant than the first insulating layer on the first insulating layer, a step of performing a second microwave heat treatment process, a step of forming a conductive layer on the second insulating layer, and a step of performing a heat treatment process.

Effects of the Invention

[0009] According to the embodiment, defects can be healed with a low thermal budget by microwave heat treatment in the manufacturing process of the semiconductor device.

[0010] According to the embodiment, in the manufacturing process of the semiconductor device, damage to the conductive layer can be avoided and interface charges and fixed charges can be passivated in a relatively low temperature state.

[0011] According to the embodiment, the density of interface charges and fixed charges in the semiconductor device is reduced, and excellent charge mobility characteristics can be ensured.

[0012] According to the embodiment, while minimizing the interface reaction by heat treatment at a low temperature, the interface charges and fixed charges can be passivated.

[0013] According to the embodiment, the characteristics of PMOS NBTI (Negative Bias Temperature Instability) of the semiconductor device can be improved.

[0014] According to the embodiment, by applying microwaves to the semiconductor to remove unstable bonds between the atoms remaining at the interface and bonding the atoms remaining at the interface using atoms such as hydrogen (H), fluorine (F), or chlorine (Cl), the characteristics of the semiconductor device can be improved.

Brief Description of the Drawings

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Modes for Carrying Out the Invention

[0016] Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily understand and reproduce them. When it is determined that a specific description of related known functions or configurations obscures the gist of the embodiments of the present invention in explaining the present invention, the detailed description thereof can be omitted. Since the terms used in this specification can be sufficiently deformed according to the intentions, conventions, etc. of the user or operator, each term should be defined based on the content throughout this specification.

[0017] Also, the foregoing and further aspects of the invention will become apparent from the embodiments described hereinafter. The configurations of the optionally described aspects and optionally described embodiments in this specification can be freely combined with each other as long as it is not obvious to those skilled in the art that they are technically contradictory even if they are shown as a single integrated configuration in the drawings, unless otherwise stated.

[0018] Therefore, it should be understood that the embodiments described in this specification and the configurations shown in the drawings are only preferred embodiments of the present invention and do not represent any of the technical ideas of the present invention, so there can be various equivalents and modifications that can replace them at the time of this application.

[0019] FIG. 1 is a diagram showing a method of manufacturing a semiconductor device according to an embodiment.

[0020] A method of manufacturing a semiconductor device according to an embodiment may include: a step (a) of forming a first insulating layer 110 on a substrate 100; a step (b) of performing a heat treatment process of a first microwave (MW); a step (c) of forming a conductive layer 120 on the first insulating layer; and a step (d) of performing a hydrogen heat treatment process.

[0021] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Usually, on the surface of a substrate with a silicon (Si) component, there are silicon atoms with a certain density, and most of them combine with oxygen during the SiO2 formation process. However, among these, at about 1% or less, dangling bonds are formed, and the electrical characteristics of the semiconductor device may deteriorate due to these weak bonds, that is, defects.

[0022] In one embodiment, the step (b) in which the heat treatment process of the first microwave (MW) is performed may be performed in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200 °C to 500 °C. Depending on the embodiment, the step (b) in which the heat treatment process of the first microwave (MW) is performed may be performed in a frequency band range of 1 GHz to 5 GHz. Preferably, the step (b) in which the heat treatment process of the first microwave (MW) is performed may be performed in a frequency band of 2.45 GHz and a temperature range of 250 °C to 450 °C for 0.5 minutes to 120 minutes.

[0023] The temperature conditions can be determined by the intensity of the microwave (MW). The heat treatment with microwave (MW) may not only enable short heat treatment but also selective heating and may have the characteristic of a low thermal budget. The heat treatment with microwave (MW) promotes the rotational and vibrational motions of silicon atoms or oxygen molecules, and defects caused by the formation of dangling bonds can be healed. Also, the dangling bonds that have not been healed by the heat treatment with microwave (MW) can be changed into stable Si-H bonds by the hydrogen treatment process described later.

[0024] In one embodiment, step (c) of forming the conductive layer 120 on the first insulating layer 110 may mean a metallization process. The conductive layer 120 may include a circuit pattern, an electrode, a source / drain, or a wiring. The conductive layer 120 may overlap the entire first insulating layer 110 or may partially overlap it.

[0025] In one embodiment, step (d) of performing a heat treatment process of hydrogen (H2) may be performed after step (c). Step (d) of performing a heat treatment process of hydrogen (H2) is preferably performed in a hydrogen atmosphere of 3% to 10%, in a pressure range of 2 atmospheres to 50 atmospheres, and in a temperature range of 200°C to 500°C (preferably 350°C to 450°C). The gas other than hydrogen may be nitrogen (N2). Although the explosion risk in a flammable environment may increase when the hydrogen concentration becomes 10% or more, it can be used if it is possible in the design of the hydrogen heat treatment apparatus, so the use of hydrogen at a concentration higher than that is not excluded. For example, step (d) of performing a heat treatment process of hydrogen (H2) may be performed in a hydrogen atmosphere of 90% to 100%.

[0026] By these processes, interface charges and fixed charges can be passivated without damaging the conductive layer 120 at a relatively low temperature. As a result, the density of interface charges and fixed charges is reduced, and excellent electron mobility characteristics can be ensured. Hydrogen may include deuterium (D2).

[0027] FIG. 2 is a diagram showing a method of manufacturing a semiconductor device according to another embodiment.

[0028] A method for manufacturing a semiconductor device by heat treatment according to another embodiment may include: a step (a) of forming a first insulating layer 110 on a substrate; a step (b) of performing a heat treatment process of a first microwave (MW); a step (c) of forming a second insulating layer 130 having a dielectric constant higher than that of the first insulating layer on the first insulating layer; a step (d) of performing a heat treatment process of a second microwave; a step (e) of forming a conductive layer 120 on the second insulating layer; and a step (f) of performing a heat treatment process of hydrogen (H2).

[0029] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Usually, there are silicon atoms with a certain density on the surface of a substrate of silicon (Si) component, and most of them are bonded to oxygen by the formation process of SiO2. However, among these, less than about 1% forms dangling bonds, and the electrical characteristics of the semiconductor device may deteriorate due to these weak bonds, that is, defects.

[0030] In one embodiment, the step (b) of performing the heat treatment process of the first microwave (MW) may be performed in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200 °C to 500 °C. According to an embodiment, the step (b) of performing the heat treatment process of the first microwave (MW) may be performed in a frequency band range of 1 GHz to 5 GHz. Preferably, the step (b) of performing the heat treatment process of the first microwave (MW) may be performed in a frequency band of 2.45 GHz and a temperature range of 250 °C to 450 °C for 0.5 minutes to 120 minutes.

[0031] The temperature condition can be determined by the intensity of microwave (MW). The heat treatment with microwave (MW) not only enables short heat treatment but also selective heating, and may have the characteristic of low thermal budget. By the heat treatment with microwave (MW), the rotational and vibrational motions of silicon atoms or oxygen molecules are promoted, and defects caused by the formation of dangling bonds can be healed. Also, the dangling bonds that have not been healed by the heat treatment with microwave (MW) can be changed into stable Si-H bonds by the hydrogen treatment process described later.

[0032] In the step (c) where the second insulating layer 130 having a higher dielectric constant than the first insulating layer is formed on the first insulating layer 110, the dielectric constant of the second insulating layer may be even larger than the dielectric constant of the first insulating layer. For example, the second insulating layer 130 may contain at least one component of HfO2, HfSi x , HfAl x , HfSiO. Preferably, the second insulating layer 130 may contain a component of hafnium oxide (HfO2).

[0033] The step (d) in which the second microwave (MW) heat treatment process is performed may be performed in a frequency band range of 5.7 GHz to 5.9 GHz and a temperature range of 200 °C to 500 °C. In other embodiments, the step (d) in which the second microwave (MW) heat treatment process is performed may be performed in a frequency band range of 4 GHz to 7 GHz. In the second insulating layer 130, the ratio of dangling bonds may be high due to the characteristic of high dielectric constant (Hig-K). Therefore, a high frequency band can be applied. However, this is only one example, and the step (d) in which the second microwave (MW) heat treatment process is performed may be performed in a frequency band range of 2.4 GHz to 2.5 GHz or 1 GHz to 5 GHz.

[0034] In one embodiment, step (e) of forming the conductive layer 120 on the second insulating layer 130 may mean a metallization process. The conductive layer 120 may include a circuit pattern, an electrode, a source / drain, or a wiring. The conductive layer 120 may overlap the entire second insulating layer 130 or may partially overlap it.

[0035] In other embodiments, a third insulating layer (not shown) may be formed between the conductive layer 120 and the second insulating layer 130.

[0036] In one embodiment, step (f) of performing a heat treatment process of hydrogen (H2) may be performed after step (e). Step (f) of performing a heat treatment process of hydrogen (H2) is preferably performed in a hydrogen atmosphere of 3% to 10% and in a pressure range of 2 atmospheres to 50 atmospheres and in a temperature range of 200°C to 500°C (preferably 350°C to 450°C). The gas other than hydrogen may be nitrogen (N2). Although the explosion risk in a flammable environment may increase when the hydrogen concentration becomes 10% or more, it can be used if it is possible in the design of the hydrogen heat treatment apparatus, so the use of hydrogen at a concentration higher than that is not excluded. For example, step (f) of performing a heat treatment process of hydrogen (H2) may be performed in a hydrogen atmosphere of 90% to 100%.

[0037] By performing these steps, interface charges and fixed charges can be passivated without damaging the conductive layer 120 at a relatively low temperature, and defects that have not been healed by microwave heat treatment can be passivated. As a result, the density of interface charges and fixed charges is reduced, and excellent electron mobility characteristics can be ensured. Hydrogen may include deuterium (D2).

[0038] FIG. 3 is a diagram showing the electron mobility characteristics of a semiconductor device manufactured according to the embodiment of FIG. 2.

[0039] Referring to Fig. 3, for a semiconductor device heat-treated in the microwave frequency band of 2.45 GHz, while gradually increasing the hydrogen pressure at a temperature of 400 °C for 10 minutes, the electron mobility of the semiconductor device was measured. As a result, in the pressure range of 2 atmospheres to 50 atmospheres, the electron mobility increases significantly.

[0040] Fig. 4 is a diagram showing a method for manufacturing a semiconductor device according to still another embodiment.

[0041] A method for manufacturing a semiconductor device by heat treatment according to an embodiment may include a step (a) of forming a first insulating layer on a substrate, a step (b) of performing a heat treatment process of a first microwave, a step (c) of forming a conductive layer on the first insulating layer, and a step (d) of performing a heat treatment process of fluorine (F2) or chlorine (Cl).

[0042] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Usually, there are silicon atoms with a certain density on the surface of a substrate containing a silicon (Si) component, and most of them combine with oxygen during the SiO2 formation process. However, among these, less than about 1% form dangling bonds, and the electrical characteristics of the semiconductor device may deteriorate due to these weak bonds, that is, defects.

[0043] In one embodiment, the step (b) of performing the heat treatment process of the first microwave (MW) may be performed in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200 °C to 500 °C. According to an embodiment, the step (b) of performing the heat treatment process of the first microwave (MW) may be performed in a frequency band range of 1 GHz to 5 GHz. Preferably, the step (b) of performing the heat treatment process of the first microwave (MW) may be performed in a frequency band of 2.45 GHz and a temperature range of 250 °C to 450 °C for 0.5 minutes to 120 minutes.

[0044] The temperature condition can be determined by the intensity of microwaves (MW). The heat treatment with microwaves (MW) not only enables short heat treatment but also selective heating, and may have the characteristics of a low thermal budget. The heat treatment with microwaves (MW) promotes the rotational and vibrational motions of silicon atoms or oxygen molecules, and defects caused by the formation of dangling bonds can be healed. Also, the dangling bonds that are not healed by the heat treatment with microwaves (MW) can be changed into stable Si-F bonds or Si-Cl bonds during the heat treatment process of fluorine (F2) or chlorine (Cl) described later.

[0045] The step (c) in which the conductive layer 120 is formed on the first insulating layer 110 according to an embodiment may mean a metallization process. The conductive layer 120 may include a circuit pattern, an electrode, a source / drain, or a wiring. The conductive layer 120 can also overlap the entire first insulating layer 110 or partially overlap it.

[0046] The step (d) in which the heat treatment process of fluorine (F2) or chlorine (Cl) according to an embodiment is performed may be performed after the above step (c). The step (d) in which the heat treatment process of fluorine (F2) or chlorine (Cl) is performed may be performed for 10 to 30 minutes in a concentration range of 0.1% to 1% and a temperature range of 300°C to 500°C. In addition to fluorine (F2) or chlorine (Cl), the gas occupying 99.9% to 99% may be an inert gas (for example, argon (Ar)). It is not necessarily required to use fluorine (F2) gas, and other gases containing fluorine (F) can also be used depending on the embodiment.

[0047] Depending on the embodiment, the concentration of fluorine (F2) or chlorine (Cl) may be 1% or more. For example, the concentration of fluorine (F2) or chlorine (Cl) in the step (d) in which the heat treatment process of fluorine (F2) or chlorine (Cl) is performed may be 90% to 100%.

[0048] Generally, fluorine (F2) and chlorine (Cl) have the characteristic of high reactivity. By performing a heat treatment process of fluorine (F2) or chlorine (Cl), interface charges and fixed charges can be passivated at a relatively low temperature without damaging the conductive layer 120. As a result, the density of interface charges and fixed charges becomes low, ensuring excellent electron mobility characteristics and enabling the manufacture of highly reliable devices.

[0049] FIG. 5 is a diagram showing a method of manufacturing a semiconductor device according to still another embodiment.

[0050] A method of manufacturing a semiconductor device by heat treatment according to an embodiment may include: a step (a) of forming a first insulating layer 110 on a substrate 100; a step (b) of performing a heat treatment process of a first microwave (MW); a step (c) of forming a second insulating layer 130 having a dielectric constant higher than that of the first insulating layer on the first insulating layer 110; a step (d) of performing a heat treatment process of a second microwave (MW); a step (e) of forming a conductive layer 120 on the second insulating layer 130; and a step (f) of performing a heat treatment process of fluorine (F2) or chlorine (Cl).

[0051] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Generally, there are a certain density of silicon atoms on the surface of a substrate of silicon (Si) component, and most of them are bonded to oxygen by the formation process of SiO2. However, among these, less than about 1% forms dangling bonds, and the electrical characteristics of the semiconductor device may deteriorate due to these weak bonds, that is, defects.

[0052] In one embodiment, the step (b) in which the heat treatment process of the first microwave (MW) is performed may be performed in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200 °C to 500 °C. According to an embodiment, the step (b) in which the heat treatment process of the first microwave (MW) is performed may be performed in a frequency band range of 1 GHz to 5 GHz. Preferably, the step (b) in which the heat treatment process of the first microwave (MW) is performed may be performed in a frequency band of 2.45 GHz and a temperature range of 250 °C to 450 °C for 0.5 minutes to 120 minutes.

[0053] The temperature condition can be determined by the intensity of the microwave (MW). The heat treatment with microwave (MW) not only enables short heat treatment but also selective heating, and may have the characteristic of a low thermal budget. By the heat treatment with microwave (MW), the rotational and vibrational motions of silicon atoms or oxygen molecules are promoted, and defects caused by the formation of dangling bonds can be healed. In addition, the dangling bonds not healed by the heat treatment with microwave (MW) can be changed into stable Si-F bonds or Si-Cl bonds in the subsequent heat treatment process with fluorine (F2) or chlorine (Cl).

[0054] In the step (c) in which the second insulating layer 130 having a higher dielectric constant than the first insulating layer is formed on the first insulating layer 110, the dielectric constant of the second insulating layer may be even larger than the dielectric constant of the first insulating layer. For example, the second insulating layer 130 may contain any component of HfO2, HfSi x , HfAl x , HfSiO. Preferably, the second insulating layer 130 may contain a component of hafnium oxide (HfO2).

[0055] The step (d) where the heat treatment process of the second microwave (MW) is performed may be carried out in a frequency band range of 5.7 GHz to 5.9 GHz and a temperature range of 200 °C to 500 °C. The step (d) where the heat treatment process of the second microwave (MW) is performed may be carried out in a frequency band range of 4 GHz to 7 GHz. In the second insulating layer 130, the proportion of dangling bonds may be high due to the characteristics of high permittivity (High-K). Therefore, a high frequency band can be applied. However, this is only one embodiment, and the step (d) where the heat treatment process of the second microwave (MW) is performed may be carried out in a frequency band range of 2.4 GHz to 2.5 GHz or 1 GHz to 5 GHz.

[0056] The step (e) where the conductive layer 120 is formed on the second insulating layer 130 according to one embodiment may mean a metallization process. The conductive layer 120 may include a circuit pattern, an electrode, a source / drain, or a wiring. The conductive layer 120 can also overlap the entire first insulating layer 110 or partially overlap it.

[0057] The step (f) where the heat treatment process of fluorine (F2) or chlorine (Cl) is performed according to one embodiment may be carried out after the above step (e). The step (f) where the heat treatment process of fluorine (F2) or chlorine (Cl) is performed may be carried out in a concentration range of 0.1% to 1% and a temperature range of 300 °C to 500 °C for 10 minutes to 30 minutes. In addition to fluorine (F2) or chlorine (Cl), the gas accounting for 99.9% to 99% may be an inert gas (for example, argon (Ar)). It is not necessarily required to use fluorine (F2) gas, and other gases containing fluorine (F) can also be used according to the embodiment.

[0058] According to the embodiment, the concentration of fluorine (F2) or chlorine (Cl) may be 1% or more. For example, the concentration of fluorine (F2) or chlorine (Cl) in the step (f) where the heat treatment process of fluorine (F2) or chlorine (Cl) is performed may be 90% to 100%.

[0059] By performing these heat treatment steps of fluorine (F2) or chlorine (Cl), it is possible to passivate interface charges and fixed charges at a relatively low temperature without damaging the conductive layer 120. As a result, defects that have not been healed by microwave heat treatment can be passivated. Also, thereby, the density of interface charges and fixed charges is reduced, excellent electron mobility characteristics are ensured, and a highly reliable device can be manufactured.

[0060] According to one embodiment, after the step (f) in which the heat treatment step of fluorine (F2) or chlorine (Cl) is performed, the step (f) in which the heat treatment step of hydrogen (H2) in FIG. 2 is performed may be further performed. Thereby, the passivation effect by hydrogen heat treatment can be further increased.

[0061] FIG. 6 is a diagram showing the electron mobility characteristics of the semiconductor device manufactured according to the embodiment of FIG. 5.

[0062] Referring to FIG. 6, for a semiconductor device heat-treated in a microwave frequency band of 5.8 GHz, while gradually increasing the temperature of the fluorine (F2) environment for 20 minutes, as a result of measuring the electron mobility, in the temperature range of 300°C to 500°C, the electron mobility increases significantly.

[0063] As described above, the embodiments have been described with reference to the exemplary drawings, but the invention is not limited by the embodiments and drawings disclosed in this specification, and various modifications can be made by an ordinary technician. In the embodiments, even if the effects due to the configuration of the invention are not explicitly described, other effects predictable by the configuration should also be recognized.

Claims

1. A step of forming an insulating layer on a substrate; A step of performing a heat treatment process using microwaves; A step of forming a conductive layer on the insulating layer; A step of performing a heat treatment process; comprising: A method for manufacturing a semiconductor device.

2. The insulating layer contains silica (SiO ２ ). The method for manufacturing a semiconductor device according to Claim 1.

3. The step of performing the heat treatment process using microwaves is performed in a temperature range of 200°C to 500°C, The method for manufacturing a semiconductor device according to Claim 1.

4. The heat treatment process is performed in a gas atmosphere containing at least one of hydrogen, fluorine, and chlorine, The method for manufacturing a semiconductor device according to Claim 1.

5. The heat treatment process is performed in a pressure range of 2 atmospheres to 50 atmospheres and a temperature range of 200°C to 500°C, The method for manufacturing a semiconductor device according to Claim 4.

6. A step of forming a first insulating layer on a substrate; A step of performing a heat treatment process using a first microwave; A step of forming a second insulating layer having a higher dielectric constant than the first insulating layer on the first insulating layer; A step of performing a heat treatment process using a second microwave; A step of forming a conductive layer on the second insulating layer; A step of performing a heat treatment process; comprising: A method for manufacturing a semiconductor device.

7. The first insulating layer contains a silica (SiO ２ ), and the second insulating layer contains a hafnium oxide (HfO ２ ). The method for manufacturing a semiconductor device according to Claim 6.

8. The heat treatment process using the first microwave or the heat treatment process using the second microwave is performed in a temperature range of 200°C to 500°C, The method for manufacturing a semiconductor device according to Claim 6.

9. The heat treatment process is performed in a gas atmosphere containing at least one of hydrogen, fluorine, and chlorine, The method for manufacturing a semiconductor device according to Claim 6.

10. The heat treatment process is performed in a pressure range of 2 atmospheres to 50 atmospheres and a temperature range of 200°C to 500°C, The method for manufacturing a semiconductor device according to Claim 9.

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