Manufacturing method for semiconductor devices

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 (for example, SiO2) are widely used. In recent years, High-K (high dielectric constant) substances (for example, HfO2, HfSi x , HfAl x ) are also used together as active layers. Defects in the structure occur during the deposition process of these insulating substances and High-K substances. Therefore, the defects are cured by a heat treatment process. Thus, 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 during 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 during 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 during the manufacturing process of semiconductor devices.

[0004] In a prior art document (Republic of Korea Patent Registration Bulletin 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 art 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 objective of this specification is to provide a method for manufacturing a semiconductor device that can improve the reliability and electrical properties of the semiconductor device through a complex heat treatment.

[0006] The purposes of this specification are not limited to those mentioned above. Other purposes and advantages of this specification not mentioned can be better understood from the examples described below. Furthermore, the purposes and advantages of this specification can be achieved by the components and combinations thereof described in the claims. [Means for solving the problem]

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

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

[0009] According to the examples, defects can be cured with a low thermal budget by microwave heat treatment during the manufacturing process of semiconductor devices.

[0010] According to the examples, in the manufacturing process of a semiconductor device, it is possible to passivate the interface charge and fixed charge without damaging the conductive layer at a relatively low temperature.

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

[0012] According to the examples, interfacial reactions can be minimized by low-temperature heat treatment, while interfacial charges and fixed charges can be passivated.

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

[0014] According to the examples, the properties of a semiconductor device can be improved by applying microwaves to a semiconductor to remove unstable bonds between atoms remaining at the interface, and then using atoms such as hydrogen (H), fluorine (F), or chlorine (Cl) to bond the remaining atoms at the interface. [Brief explanation of the drawing]

[0015] [Figure 1] This figure shows a method for manufacturing a semiconductor device according to one embodiment. [Figure 2] This figure shows a method for manufacturing a semiconductor device according to another embodiment. [Figure 3] This figure shows the electron mobility characteristics of a semiconductor device manufactured according to the embodiment shown in Figure 2. [Figure 4] This figure shows a method for manufacturing a semiconductor device according to another embodiment. [Figure 5] This figure shows a method for manufacturing a semiconductor device according to another embodiment. [Figure 6] This figure shows the electron mobility characteristics of a semiconductor device manufactured according to the embodiment shown in Figure 5. [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 depending on the intention of the user or operator, conventions, etc., 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 selectively described aspects and the configurations of the selectively described embodiments in this specification should be understood to be freely combinable with each other as long as they are not technically contradictory to those skilled in the art, even if they are shown as a single integrated configuration in the drawings and unless otherwise stated.

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

[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 bond with oxygen during the SiO2 formation process. However, among these, at about 1% or less, dangling bonds are formed, and the electrical characteristics of semiconductor devices may deteriorate due to these weak bonds, that is, defects.

[0022] In one embodiment, the stage (b) where the heat treatment process of the first microwave (MW) is performed may be carried out 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 stage (b) where the heat treatment process of the first microwave (MW) is performed may be carried out in a frequency band range of 1 GHz to 5 GHz. Preferably, the stage (b) where the heat treatment process of the first microwave (MW) is performed may be carried out 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 change into stable Si-H bonds through the hydrogen treatment process described later.

[0024] In one embodiment, step (c) in which the conductive layer 120 is formed on the first insulating layer 110 may mean a metallization process. The conductive layer 120 may include circuit patterns, electrodes, sources / drains, or wiring. The conductive layer 120 may overlap the entire first insulating layer 110 or it may partially overlap it.

[0025] In one embodiment, step (d) in which the hydrogen (H2) heat treatment process is performed may be performed after step (c). The hydrogen (H2) heat treatment process (d) is preferably performed in a 3% to 10% hydrogen atmosphere, in a pressure range of 2 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 risk of explosion in a flammable environment may increase when the hydrogen concentration exceeds 10%, this does not preclude the use of higher concentrations of hydrogen, as they can be used if it is possible in the design of the hydrogen heat treatment apparatus. For example, the hydrogen (H2) heat treatment process (d) may be performed in a 90% to 100% hydrogen atmosphere.

[0026] These processes allow for passivation of interfacial charges and fixed charges at relatively low temperatures without damaging the conductive layer 120. This reduces the density of interfacial charges and fixed charges, ensuring excellent electron mobility characteristics. The hydrogen may also contain deuterium (D2).

[0027] Figure 2 shows a method for 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 the steps of: (a) forming a first insulating layer 110 on a substrate; (b) performing a first microwave (MW) heat treatment process; (c) forming a second insulating layer 130 having an even higher dielectric constant than the first insulating layer on the first insulating layer; (d) performing a second microwave heat treatment process; (e) forming a conductive layer 120 on the second insulating layer; and (f) performing a hydrogen (H2) heat treatment process.

[0029] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Normally, the surface of a silicon (Si) substrate has a certain density of silicon atoms, and most of them bond with oxygen during the SiO2 formation process. However, dangling bonds are formed in about 1% or less of these atoms, and these weak bonds, or defects, can degrade the electrical properties of the semiconductor device.

[0030] In one embodiment, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200°C to 500°C. In the embodiment, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out in a frequency band range of 1 GHz to 5 GHz. Preferably, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out 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 conditions can be determined by the intensity of the microwaves (MW). Microwave (MW) heat treatment may not only allow for short heat treatments but also enable selective heating and have a low thermal budget. Microwave (MW) heat treatment can promote the rotational and vibrational motion of silicon atoms or oxygen molecules, thereby healing defects caused by the formation of dangling bonds. Furthermore, dangling bonds that have not been healed by microwave (MW) heat treatment can be transformed into stable Si-H bonds by the hydrogen treatment process described later.

[0032] In step (c), where a second insulating layer 130 having an even 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 greater than that of the first insulating layer. For example, the second insulating layer 130 may be made of HfO2, HfSi x , HfAl x It may also contain at least one component of HfSiO. Preferably, the second insulating layer 130 may contain a component of hafnium oxide (HfO2).

[0033] The second microwave (MW) heat treatment step (d) 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 second microwave (MW) heat treatment step (d) may be performed in a frequency band range of 4 GHz to 7 GHz. The second insulating layer 130 may have a high proportion of dangling bonds due to its high dielectric constant (Hig-K) characteristic. Therefore, a high frequency band can be applied. However, this is only one embodiment, and the second microwave (MW) heat treatment step (d) 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 circuit patterns, electrodes, source / drain, or wiring. The conductive layer 120 may overlap the entire second insulating layer 130 or partially.

[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) in which the hydrogen (H2) heat treatment step is performed may be performed after step (e). The step (f) in which the hydrogen (H2) heat treatment step is performed is preferably carried out in a 3% to 10% hydrogen atmosphere, in a pressure range of 2 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 risk of explosion in a flammable environment may increase when the hydrogen concentration exceeds 10%, it can be used if it is possible in the design of the hydrogen heat treatment apparatus, so this does not preclude the use of higher concentrations of hydrogen. For example, the step (f) in which the hydrogen (H2) heat treatment step is performed may be carried out in a 90% to 100% hydrogen atmosphere.

[0037] By performing these processes, interfacial charges and fixed charges can be passivated at relatively low temperatures without damaging the conductive layer 120, and defects that have not been healed by microwave heat treatment can be passivated. This reduces the density of interfacial charges and fixed charges, ensuring excellent electron mobility properties. Hydrogen may also contain deuterium (D2).

[0038] Figure 3 shows the electron mobility characteristics of a semiconductor device manufactured according to the embodiment shown in Figure 2.

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

[0040] Figure 4 shows a diagram illustrating a method for manufacturing a semiconductor device according to yet another embodiment.

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

[0042] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Normally, the surface of a silicon (Si) substrate has a certain density of silicon atoms, and most of them bond with oxygen during the SiO2 formation process. However, dangling bonds are formed in about 1% or less of these atoms, and these weak bonds, or defects, can degrade the electrical properties of the semiconductor device.

[0043] In one embodiment, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200°C to 500°C. In the embodiment, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out in a frequency band range of 1 GHz to 5 GHz. Preferably, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out 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 conditions can be determined by the intensity of the microwave (MW). Microwave (MW) heat treatment may not only allow for short heat treatment times but also enable selective heating and have a low thermal budget. Microwave (MW) heat treatment can promote the rotational and vibrational motion of silicon atoms or oxygen molecules, thereby healing defects caused by the formation of dangling bonds. Furthermore, dangling bonds that have not been healed by microwave (MW) heat treatment can be transformed into stable Si-F bonds or Si-Cl bonds during the fluorine (F2) or chlorine (Cl) heat treatment process described later.

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

[0046] Step (d) in which the fluorine (F2) or chlorine (Cl) heat treatment step according to one embodiment is performed may be performed after step (c) above. Step (d) in which the fluorine (F2) or chlorine (Cl) heat treatment step is performed may be carried out for 10 to 30 minutes at 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 making up 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) may be used depending on the embodiment.

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

[0048] Typically, fluorine (F2) and chlorine (Cl) are highly reactive. By performing a heat treatment process with fluorine (F2) or chlorine (Cl), interfacial charges and fixed charges can be passivated at relatively low temperatures without damaging the conductive layer 120. This reduces the density of interfacial charges and fixed charges, ensuring excellent electron mobility characteristics and enabling the manufacture of highly reliable devices.

[0049] Figure 5 shows a method for manufacturing a semiconductor device according to yet another embodiment.

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

[0051] The substrate 100 may contain a silicon (Si) component. The first insulating layer 110 may contain a silica (SiO2) component. Normally, the surface of a silicon (Si) substrate has a certain density of silicon atoms, and most of them bond with oxygen during the SiO2 formation process. However, dangling bonds are formed in about 1% or less of these atoms, and these weak bonds, or defects, can degrade the electrical properties of the semiconductor device.

[0052] In one embodiment, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out in a frequency band range of 2.4 GHz to 2.5 GHz and a temperature range of 200°C to 500°C. In the embodiment, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out in a frequency band range of 1 GHz to 5 GHz. Preferably, step (b) in which the first microwave (MW) heat treatment process is performed may be carried out 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 conditions can be determined by the intensity of the microwaves (MW). Microwave (MW) heat treatment may not only allow for short heat treatments but also enable selective heating and have a low thermal budget. Microwave (MW) heat treatment can promote the rotational and vibrational motion of silicon atoms or oxygen molecules, thereby healing defects caused by the formation of dangling bonds. Furthermore, dangling bonds that have not been healed by microwave (MW) heat treatment may be transformed into stable Si-F bonds or Si-Cl bonds during the fluorine (F2) or chlorine (Cl) heat treatment process described later.

[0054] In step (c), where a second insulating layer 130 having an even 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 greater than that of the first insulating layer. For example, the second insulating layer 130 may be made of HfO2, HfSi x , HfAl x It may contain either HfSiO or another component. Preferably, the second insulating layer 130 may contain hafnium oxide (HfO2).

[0055] The second microwave (MW) heat treatment step (d) 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. The second microwave (MW) heat treatment step (d) may also be performed 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 high dielectric constant (High-K) characteristic. Therefore, a high frequency band can be applied. However, this is only one embodiment, and the second microwave (MW) heat treatment step (d) may also be performed in a frequency band range of 2.4 GHz to 2.5 GHz or a frequency band range of 1 GHz to 5 GHz.

[0056] Step (e) in which 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 circuit patterns, electrodes, source / drain, or wiring. The conductive layer 120 may overlap the entire first insulating layer 110 or partially.

[0057] Step (f) in which the fluorine (F2) or chlorine (Cl) heat treatment step is performed according to one embodiment may be performed after step (e) above. Step (f) in which the fluorine (F2) or chlorine (Cl) heat treatment step is performed may be carried out for 10 to 30 minutes at 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 making up 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) may be used depending on the embodiment.

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

[0059] These fluorine (F2) or chlorine (Cl) heat treatment processes allow for passivation of interfacial and fixed charges at relatively low temperatures without damaging the conductive layer 120. This enables the passivation of defects that have not been cured by microwave heat treatment. Furthermore, this reduces the density of interfacial and fixed charges, ensuring excellent electron mobility characteristics and enabling the manufacture of highly reliable devices.

[0060] In one embodiment, after the step (f) in which a fluorine (F2) or chlorine (Cl) heat treatment step is performed, the step (f) in which a hydrogen (H2) heat treatment step shown in Figure 2 is performed may be further carried out. This may further increase the passivation effect due to the hydrogen heat treatment.

[0061] Figure 6 shows the electron mobility characteristics of a semiconductor device manufactured according to the embodiment shown in Figure 5.

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

[0063] As described above, the embodiments have been explained with reference to the illustrative drawings, but the invention is not limited by the embodiments and drawings disclosed herein, and various modifications can be made by those skilled in the art. Even if the effects of the configuration of the invention are not explicitly described in the embodiments, other effects that can be predicted by such configurations should also be recognized.

Claims

1. The step of forming an insulating layer on the substrate, The step after the step in which the insulating layer is formed is followed by a step in which a microwave heat treatment process is performed. Following the step in which the microwave heat treatment process is performed, a step is taken in which a conductive layer is formed on the insulating layer. After the step in which the conductive layer is formed, a heat treatment step is performed, including, A method for manufacturing a semiconductor device.

2. The insulating layer is made of silica (SiO ２ ) Contains the following ingredients A method for manufacturing a semiconductor device according to claim 1.

3. The step in which the microwave heat treatment process is carried out is: It is carried out in a temperature range of 200°C to 500°C. A method for manufacturing a semiconductor device according to claim 1.

4. The aforementioned heat treatment step is The process is carried out in a gas atmosphere containing at least one of hydrogen, fluorine, or chlorine. A method for manufacturing a semiconductor device according to claim 1.

5. The aforementioned heat treatment step is It is performed in a pressure range of 2 to 50 atmospheres and a temperature range of 300°C to 500°C. The method for manufacturing a semiconductor device according to claim 4.

6. The step of forming a first insulating layer on the substrate, The step after the step in which the first insulating layer is formed is followed by a step in which a first microwave heat treatment step is performed, The process includes the step of forming a second insulating layer having an even higher dielectric constant than the first insulating layer on the first insulating layer, after the first microwave heat treatment step has been performed, The process is followed by a step in which a second microwave heat treatment step is performed after the step in which the second insulating layer is formed, After the second microwave heat treatment step is performed, a conductive layer is formed on the second insulating layer. After the step in which the conductive layer is formed, a heat treatment step is performed, including, A method for manufacturing a semiconductor device.

7. The first insulating layer is silica (SiO ２ The second insulating layer contains the component hafnium oxide (HfO ２ ) Contains the following ingredients The method for manufacturing a semiconductor device according to claim 6.

8. The first microwave heat treatment step or the second microwave heat treatment step is It is carried out in a temperature range of 200°C to 500°C. The method for manufacturing a semiconductor device according to claim 6.

9. The aforementioned heat treatment step is The process is carried out in a gas atmosphere containing at least one of hydrogen, fluorine, or chlorine. The method for manufacturing a semiconductor device according to claim 6.

10. The aforementioned heat treatment step is It is performed in a pressure range of 2 to 50 atmospheres and a temperature range of 300°C to 500°C. The method for manufacturing a semiconductor device according to claim 9.

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