Deposition method

Abstract

A deposition method comprising: performing multiple seed deposition cycles, each seed deposition cycle comprising: introducing a precursor; performing first scavenging treatment; introducing a co-reactant; performing second scavenging treatment; wherein in each seed deposition cycle, the concentrations of the introduced precursors are different. According to the invention, the uniformity of the deposited film layer is improved.

Description

Technical Field

[0001] This disclosure relates to the field of semiconductor manufacturing, and more particularly to a deposition method. Background Technology

[0002] In the semiconductor field, molybdenum (Mo) is a key material in the manufacture of logic and memory chips due to its excellent electrical conductivity, low coefficient of thermal expansion, and superior mechanical properties. For example, in some advanced 3D memory designs, molybdenum is used to manufacture word lines (WL) to improve signal transmission speed and reduce power consumption.

[0003] Currently, the main methods for growing molybdenum thin films are Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD). PVD molybdenum films exhibit poor step coverage, making it difficult to meet the filling requirements of high aspect ratio structures. In contrast, CVD precursor molecules can diffuse into the interior of high aspect ratio structures and undergo chemical reactions on the surface to form a thin film. This diffusion mechanism allows CVD to uniformly cover complex three-dimensional structures. Atomic Layer Deposition (ALD), derived from CVD, uses alternating pulses of precursors and co-reactants entering the reaction chamber, where a chemical adsorption reaction occurs on the substrate surface. Cyclic deposition is achieved through this process, and its self-limiting surface characteristics allow for precise control of the film thickness, which is dependent on the number of cycles. ALD is not only suitable for large-area uniform growth on planar substrates but is also particularly well-suited for filling complex shapes and deep pores. Summary of the Invention

[0004] The problem addressed by the embodiments of this disclosure is to provide a deposition method that is beneficial for improving the uniformity of the deposited film.

[0005] To address the aforementioned problems, embodiments of this disclosure provide a deposition method comprising: performing multiple sub-deposition cycles, each sub-deposition cycle comprising: introducing a precursor; performing a first scavenging treatment; introducing a co-reactant; and performing a second scavenging treatment; wherein the concentration of the introduced precursor is different in each sub-deposition cycle.

[0006] Optionally, the precursor has deposition and etching properties.

[0007] Optionally, the precursor is a halide.

[0008] Optionally, the precursor includes molybdenum pentachloride.

[0009] Optionally, the various sub-deposition cycles are performed in an increasing or decreasing order of the concentration of the introduced precursor.

[0010] Optionally, in the step of introducing the precursor, a carrier gas is used to carry the precursor in order to introduce it, and the concentration of the introduced precursor is different by adjusting the carrier gas flow rate and / or the carrier gas introduction time.

[0011] Optionally, the step of introducing the precursor includes: using a carrier gas to carry the precursor into a buffer cylinder; and pulse the precursor in the buffer cylinder into the deposition chamber.

[0012] Optionally, in the step of pulsed precursor from the buffer cylinder into the deposition chamber, the pulse times of various sub-deposition cycles correspond to the same trend in the concentration of the precursor.

[0013] Optionally, the duration of the first scavenging treatment corresponds to the same trend in the concentration of the precursor.

[0014] Optionally, the deposition temperature of the sub-deposition cycle is 300°C to 500°C.

[0015] Compared with the prior art, the technical solution of the present disclosure has the following advantages: In the deposition method provided in this disclosure, multiple sub-deposition cycles are performed, and the concentration of the precursor introduced in each sub-deposition cycle is different. In this disclosure, by dynamically adjusting and controlling the concentration of the precursor, sub-deposition cycles with different concentrations of precursor are combined to achieve a dynamic balance of the deposition reaction of different concentrations of precursor, thereby improving the uniformity of the deposited film. Attached Figure Description

[0016] Figures 1 to 5 This is a schematic diagram of each step in an embodiment of the deposition method disclosed herein. Detailed Implementation

[0017] As the background technology indicates, atomic layer deposition (ALD) can achieve high step coverage in high aspect ratio structures by depositing molybdenum thin films. However, the commonly used molybdenum dichlorodioxygenate (MoCl2O2) precursor presents several problems. Firstly, the deposition temperature of the MoCl2O2 precursor needs to exceed 500°C, which can easily damage the substrate material and other structures, or trigger unnecessary element diffusion, thus affecting device performance. Secondly, the oxygen content in the MoCl2O2 precursor leads to a higher impurity content in the film, which is detrimental to reducing the film's resistivity. Furthermore, using other precursors can make the deposition process difficult to control, resulting in uneven film deposition.

[0018] To address the aforementioned technical problems, embodiments of this disclosure provide a deposition method comprising: performing multiple sub-deposition cycles, each sub-deposition cycle comprising: introducing a precursor; performing a first scavenging treatment; introducing a co-reactant; and performing a second scavenging treatment; wherein the concentration of the introduced precursor is different in each sub-deposition cycle.

[0019] In this embodiment of the disclosure, by dynamically adjusting and controlling the concentration of the precursor, sub-deposition cycles with different concentrations of precursor are combined to achieve a dynamic balance of the deposition reaction of different concentrations of precursor, thereby improving the uniformity of the deposited film.

[0020] To make the above-mentioned objects, features and advantages of the embodiments of this disclosure more apparent and understandable, the specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings.

[0021] Figures 1 to 5 This is a schematic diagram of each step in an embodiment of the deposition method disclosed herein.

[0022] refer to Figure 1 100 items are pending processing.

[0023] The deposition process is then carried out on the workpiece 100.

[0024] Specifically, in some embodiments, the deposition method is suitable for atomic layer deposition, chemical vapor deposition, or physical vapor deposition.

[0025] In some embodiments, a high aspect ratio deposited structure 110 is formed on the workpiece 100.

[0026] As an example, the workpiece 100 can be a substrate, and the structure to be deposited 110 can be a trench on the substrate.

[0027] Specifically, in some embodiments, the deposition method on the structure to be deposited 110 is suitable for forming deep trench capacitor electrodes for dynamic random access memory (DRAM), and is also suitable for filling contact plugs or word line edges of vertical channels (Memory Holes) in 3D NAND memory, and is also suitable for forming diffusion barrier layers, seed layers and other films in high aspect ratio vias and through-silicon vias (TSVs) of logic chips.

[0028] In some embodiments, the object to be processed 100 is placed in a deposition reaction chamber to prepare for deposition.

[0029] Specifically, in some embodiments, a base film layer is formed on the surface of the structure to be deposited 110. The material of the base film layer includes titanium nitride (TiN), molybdenum nitride (MoN), and molybdenum (Mo). The structure to be deposited 110 with the base film layer is placed in the deposition reaction chamber for subsequent deposition.

[0030] Reference Figures 2 to 5 Multiple sub-deposition cycles are performed, each including: introducing a precursor; performing a first scavenging treatment; introducing a co-reactant; and performing a second scavenging treatment; wherein the concentration of the introduced precursor is different in each sub-deposition cycle.

[0031] A combination of multiple sub-deposition cycles with different precursor concentrations is used to achieve a flexible and adjustable deposition process.

[0032] Specifically, in some embodiments, in each sub-deposition cycle, a precursor is introduced to achieve chemical adsorption of the precursor on the surface of the structure to be deposited 110; then a first scavenging treatment is performed for physical purification to remove unreacted precursor molecules and generated gaseous byproducts in the chamber; then a co-reactant is introduced, and the co-reactant molecules react with the precursor layer that has been chemically adsorbed on the surface to achieve film growth; then a second scavenging treatment is performed for further physical purification to remove unreacted co-reactant molecules and newly generated gaseous byproducts in the chamber, thereby ensuring the purity and repeatability of each sub-deposition cycle.

[0033] In some embodiments, by dynamically adjusting and controlling the concentration of precursors, sub-deposition cycles with different concentrations of precursors are combined to achieve a dynamic balance of the deposition reactions of different concentrations of precursors, thereby improving the uniformity of the deposited film.

[0034] In some embodiments, there are two to four types of multi-sub-deposition cycles, which is beneficial to combine the deposition of precursors with different concentrations while making the deposition method less complex and easier to operate.

[0035] In some embodiments, the precursor has deposition and etching properties.

[0036] In other words, when the precursor undergoes a deposition reaction on the surface of the structure to be deposited 110, it also has an etching effect. Specifically, in a sub-deposition cycle, when the precursor concentration is low, the etching effect of the introduced precursor is weak, but the deposition effect is also affected by the weak diffusion ability. When the precursor concentration is high, the deposition ability of the introduced precursor is enhanced, but the dissolution etching effect is also enhanced, which will cause the deposition film to be over-etched. Therefore, the concentration of the introduced precursor is different in each sub-deposition cycle. That is, the method of combining the deposition of different concentrations of precursor is conducive to achieving a dynamic balance between the precursor deposition characteristics and etching characteristics, thereby improving the coverage uniformity of the deposition film.

[0037] Specifically, in some embodiments, for a high aspect ratio structure 110, under conditions of low-concentration precursor, the precursor is difficult to diffuse sufficiently into the depth of the structure 110, resulting in insufficient deposition at the bottom of the structure 110. Under conditions of high-concentration precursor, the precursor etching effect is enhanced, causing excessive etching of the surface film near the top of the structure 110. Therefore, this solution, by precisely controlling the precursor concentration of multiple sub-deposition cycles and coordinating with the cycle parameters of multiple sub-deposition cycles, is beneficial to achieving uniform film deposition from top to bottom on the surface of the structure 110, while also suppressing the etching effect of the precursor on the already deposited film.

[0038] In some embodiments, the precursor is a halide.

[0039] Halides are readily sublimated or vaporized at lower temperatures, making them easy to introduce into the reaction chamber. Furthermore, halides have high reactivity, which helps to improve deposition efficiency.

[0040] Specifically, in some embodiments, the precursor is a metal halide.

[0041] Metal halide precursors do not contain impurities such as oxygen and carbon, which helps reduce the content of oxygen and carbon impurities in the deposited film, thereby reducing the resistivity of the deposited film. Moreover, using metal halides as precursors allows for lower deposition temperatures, which helps reduce damage to the structure to be deposited and also helps to avoid unnecessary element diffusion, thus helping to ensure device performance.

[0042] As an example, in some embodiments, the precursor includes molybdenum pentachloride (MoCl5).

[0043] Molybdenum pentachloride possesses both deposition and etching properties, resulting in molybdenum films with good uniformity. It also effectively reduces the influence of oxygen and carbon impurities on the deposited film, thereby lowering the impurity content and thus reducing the resistivity of the deposited molybdenum film.

[0044] In other embodiments, the precursor may also include molybdenum pentafluoride (MoF5) or molybdenum hexafluoride (MoF6).

[0045] In some embodiments, during the step of introducing the precursor, the source temperature of the precursor is 80°C to 120°C.

[0046] The source temperature of the precursor is 80℃ to 120℃, that is, the source bottle of the precursor is heated to 80℃ to 120℃, which makes it easy to flexibly adjust the precursor concentration.

[0047] Specifically, in some embodiments, the saturated vapor pressure of molybdenum pentachloride is relatively low (0.14 torr @ 100°C). Heating the source bottle helps to increase its volatilization rate to maintain a sufficient precursor concentration. Moreover, with the source bottle volume, structure, and filling amount constant, increasing the source bottle temperature can increase the saturated vapor pressure of molybdenum pentachloride, but it will simultaneously enhance its etching activity. Therefore, maintaining the source temperature of the precursor at 80°C to 120°C is beneficial for precisely controlling the source bottle temperature and the precursor transport rate, so as to suppress the etching effect while ensuring the uniformity of the deposited film.

[0048] In some embodiments, multiple sub-deposition cycles are performed in order of increasing or decreasing concentration of the introduced precursor.

[0049] Multiple precursor deposition cycles proceed in an increasing or decreasing order of the introduced precursor concentration, meaning the precursor concentration changes gradually. This is more conducive to gradually adjusting the deposition reaction of different precursor concentrations to achieve dynamic equilibrium, thereby further improving the uniformity of the deposited film.

[0050] As an example, multiple sub-deposition cycles proceed in order of increasing precursor concentration, such as... Figure 2 As shown, a sub-deposition cycle with a low concentration of precursor is first performed. The etching effect of the introduced precursor is weak, but at the same time, the deposition effect is also weak due to its diffusion ability. Along the depth direction of the structure to be deposited 110, as the precursor is consumed, its concentration gradually decreases, and at the same time, the diffusion ability is weak. Therefore, the amount of precursor adsorbed in the middle and bottom of the structure to be deposited 110 is less, and the thickness of the first deposition film 210 formed is thinner. Thus, the first deposition film 210 is deposited on the surface and top of the structure to be deposited 110. Figure 3As shown, a sub-deposition cycle with a medium concentration of precursor is then performed along the depth direction of the structure to be deposited 110. Due to the higher precursor concentration at the surface and top of the structure 110, the precursor's etching effect is stronger, and the deposited film is over-etched by the precursor. In the middle of the structure 110, the precursor's deposition ability is stronger than the etching effect, i.e., the deposition rate is greater than the etching rate, thus allowing deposition in the middle of the structure 110. At the bottom of the structure 110, due to the lower precursor concentration, only a small amount or even no deposition occurs, thus forming a second deposited film 220 only in the middle of the structure 110. Figure 4 As shown, a high-concentration precursor sub-deposition cycle is finally performed. The precursor concentration is high on the surface and top of the structure to be deposited 110, and the deposition rate is lower than the etching rate, which causes the deposited film to be gradually etched. Along the depth direction of the structure to be deposited 110, the precursor concentration decreases slightly, the etching effect weakens, and the deposition rate gradually begins to exceed the etching rate, so that the third deposition film 230 is formed only in the middle and bottom of the structure to be deposited 110.

[0051] In some embodiments, the number of cycles for each sub-deposition cycle is from 10 to 100.

[0052] By controlling the number of each sub-deposition cycle, the deposition effect of each concentration of precursor can be dynamically adjusted, thereby obtaining a film thickness that meets the process requirements.

[0053] As an example, such as Figure 5 As shown, by adopting a precursor concentration gradient-cycle number combination strategy, the synergistic effect of precursor concentration gradient and the number of sub-deposition cycles is precisely controlled, achieving uniform film deposition from top to bottom on the surface of the structure to be deposited 110, forming a uniformly covered high aspect ratio stepped structure deposition layer 200.

[0054] In some embodiments, the deposition temperature of the sub-deposition cycle is 300°C to 500°C.

[0055] That is, the deposition temperature in the reaction chamber is 300℃ to 500℃. The lower deposition temperature is beneficial to reduce the damage to the workpiece 100 to be treated and to reduce the degree of element diffusion.

[0056] Specifically, in some embodiments, metal halides are used as precursors, allowing for lower deposition temperatures and facilitating low-temperature atomic layer deposition processes, thereby further forming high-quality deposited films.

[0057] In some embodiments, the reaction chamber pressure of the sub-deposition cycle is from 0.1 torr to 80 torr.

[0058] The reaction chamber pressure of the sub-deposition cycle is 0.1 torr to 80 torr, which is conducive to better filling. At the same time, it is beneficial to reduce the etching ability of the precursor by adjusting the chamber pressure.

[0059] In some embodiments, during the step of introducing the precursor, a carrier gas is used to carry the precursor in order to introduce it, and the concentration of the introduced precursor is varied by adjusting the carrier gas flow rate and / or the carrier gas introduction time.

[0060] By using a carrier gas to carry the precursor into the reaction chamber, the concentration of the precursor can be adjusted by regulating the carrier gas flow rate and / or the carrier gas introduction time.

[0061] As an example, in some embodiments, the deposition method includes a first sub-deposition cycle, a second sub-deposition cycle, and a third sub-deposition cycle with progressively increasing precursor concentrations; the carrier gas flow rate of the first sub-deposition cycle is 100 sccm to 500 sccm, and the carrier gas introduction time is 1 s to 30 s; the carrier gas flow rate of the second sub-deposition cycle is 500 sccm to 1000 sccm, and the carrier gas introduction time is 30 s to 60 s; the carrier gas flow rate of the third sub-deposition cycle is 1000 sccm to 2000 sccm, and the carrier gas introduction time is 60 s to 120 s.

[0062] By gradually increasing the carrier gas flow rate and carrier gas introduction time in the first, second, and third sub-deposition cycles, the precursor concentration in the first, second, and third sub-deposition cycles can be gradually increased.

[0063] As an example, in some embodiments, argon is used as the carrier gas.

[0064] Specifically, in some embodiments, the step of introducing the precursor includes: using a carrier gas to carry the precursor into a buffer cylinder; and pulse the precursor in the buffer cylinder into the deposition chamber.

[0065] Using buffer cylinders helps stabilize the vapor pressure of precursors and achieve rapid pulses, thereby improving precursor utilization efficiency.

[0066] Accordingly, in some embodiments, in the step of pulsed precursors from the buffer cylinder into the deposition chamber, the pulse duration of multiple deposition cycles corresponds to the precursor concentration and has the same trend.

[0067] In other words, the higher the precursor concentration, the longer the pulse time of the sub-deposition cycle, and the shorter the pulse time of the sub-deposition cycle, the lower the precursor concentration. Adjusting the pulse time can correspondingly adjust the precursor concentration.

[0068] As an example, in some embodiments, the deposition method includes a first sub-deposition cycle, a second sub-deposition cycle, and a third sub-deposition cycle with the precursor concentration increasing sequentially; the pulse time of the first sub-deposition cycle is 0.5 s to 3 s; the pulse time of the second sub-deposition cycle is 3 s to 6 s; and the pulse time of the third sub-deposition cycle is 6 s to 10 s.

[0069] As an example, in some embodiments, argon is used for the first scavenging process.

[0070] In some embodiments, the duration of the first scavenging treatment corresponds to the same trend in the concentration of the precursor.

[0071] The higher the precursor concentration, the more unreacted precursor molecules and gaseous byproducts are generated, and the longer the duration of the first scavenging treatment is. This is beneficial for thoroughly removing unreacted precursor molecules and gaseous byproducts. In other words, the higher the precursor concentration of a sub-deposition cycle, the longer the first scavenging treatment time, and the lower the precursor concentration of a sub-deposition cycle, the shorter the first scavenging treatment time.

[0072] As an example, in some embodiments, the deposition method includes a first sub-deposition cycle, a second sub-deposition cycle, and a third sub-deposition cycle with progressively increasing precursor concentrations; the first scavenging treatment time of the first sub-deposition cycle is not less than 2 seconds; the first scavenging treatment time of the second sub-deposition cycle is not less than 6 seconds; and the first scavenging treatment time of the third sub-deposition cycle is not less than 10 seconds.

[0073] As an example, in some embodiments, hydrogen is used as a co-reactant introduced into the reaction chamber.

[0074] In some embodiments, the process parameters for introducing the co-reactant are the same in each sub-deposition cycle.

[0075] As an example, in some embodiments, argon is used for the second scavenging process.

[0076] Accordingly, in some embodiments, the duration of the second scavenging treatment corresponds to the same trend in the concentration of the precursor.

[0077] As an example, the following illustrates the specific steps of a deposition method, but this disclosure is not limited to the following description.

[0078] In some embodiments, molybdenum pentachloride is used as a metal precursor, hydrogen is used as a co-reactant, and argon is used as a carrier gas and purge gas, wherein the source temperature of molybdenum pentachloride is 100°C.

[0079] In some embodiments, the workpiece 100 is placed in a deposition reaction chamber at a temperature of 300°C to 500°C and a pressure of 0.1 torr to 80 torr, and deposition is initiated according to the following steps.

[0080] Step S1: Using argon as the carrier gas, molybdenum pentachloride vapor is carried from the source bottle to the buffer cylinder. The carrier gas introduction time is 1s to 30s, and the carrier gas flow rate is 100sccm to 500sccm. Then, molybdenum pentachloride vapor is pulsed into the chamber for 0.5s to 3s to allow it to react chemically and be adsorbed on the surface of the structure to be deposited 110. Step S2: Use argon gas to purge the chamber for the first purging treatment to remove excess precursors and byproducts generated by chemical reaction and adsorption in the reaction chamber. The purging time is greater than 2 seconds.

[0081] Step S3: Pulse hydrogen gas, the co-reactant, into the chamber for 0.5s to 10s, with a gas flow rate of 100sccm to 50000sccm, so that it reacts with the metal precursor adsorbed on the surface of the structure to be deposited 110. Step S4: Use argon gas to purge the chamber for a second purging process to remove excess co-reactant gases and byproducts generated by the chemical reaction in the reaction chamber. The purging time is greater than 2 seconds.

[0082] Steps S1 to S4 are the first seed deposition cycle. Steps S1 to S4 are repeated. By controlling the concentration of molybdenum pentachloride, the molybdenum film is controlled to be deposited only on the surface and top of the structure to be deposited 110.

[0083] Step S5: Using argon as the carrier gas, molybdenum pentachloride vapor is carried from the source bottle to the buffer cylinder. The carrier gas introduction time is 30s to 60s, and the carrier gas flow rate is 500sccm to 1000sccm. Then, molybdenum pentachloride vapor is pulsed into the chamber for 3s to 6s to allow it to react chemically and be adsorbed on the surface of the structure to be deposited 110. Step S6: Use argon gas to purge the chamber for the first purging treatment to remove excess precursors and byproducts generated by chemical reaction and adsorption in the reaction chamber. The purging time is greater than 6 seconds.

[0084] Step S7: Pulse hydrogen gas, the co-reactant, into the chamber for 0.5s to 10s, with a gas flow rate of 100sccm to 50000sccm, so that it reacts with the metal precursor adsorbed on the surface of the structure to be deposited 110. Step S8: Use argon gas to purge the chamber for a second purging process to remove excess co-reactant gases and byproducts generated by the chemical reaction in the reaction chamber. The purging time is greater than 4 seconds.

[0085] Steps S5 to S8 are the second seed deposition cycle. Steps S5 to S8 are repeated. By controlling the concentration of molybdenum pentachloride, the molybdenum film is deposited only in the middle of the structure to be deposited 110. On the surface and top of the structure to be deposited 110, the molybdenum film deposition and molybdenum pentachloride etching reach a balance due to the higher concentration of molybdenum pentachloride. At the bottom of the structure sheet, the molybdenum pentachloride concentration is lower, and there is only a small amount or even no molybdenum film deposition.

[0086] Step S9: Using argon as the carrier gas, molybdenum pentachloride vapor is carried from the source bottle to the buffer cylinder. The carrier gas introduction time is 60s to 120s, and the carrier gas flow rate is 1000sccm to 2000sccm. Then, molybdenum pentachloride vapor is pulsed into the cavity for 6s to 10s to allow it to react chemically and be adsorbed on the surface of the structure to be deposited 110. Step S10: Use argon gas to purge the chamber for the first purging treatment to remove excess precursors and byproducts generated by chemical reaction and adsorption in the reaction chamber. The purging time is greater than 10 seconds.

[0087] Step S11: Pulse hydrogen gas, the co-reactant, into the cavity for 0.5s to 10s, with a gas flow rate of 100sccm to 50000sccm, so that it reacts with the metal precursor adsorbed on the surface of the structure to be deposited 110. Step S12: Use argon gas to purge the chamber for a second purging process to remove excess co-reactant gases and byproducts generated by the chemical reaction in the reaction chamber. The purging time is greater than 6 seconds.

[0088] Steps S9 to S12 are the third seed deposition cycle. Steps S9 to S12 are repeated. By controlling the concentration of molybdenum pentachloride, the molybdenum film is controlled to be deposited only at the bottom of the structure to be deposited 110. On the surface and top of the structure to be deposited 110, the molybdenum film is etched by molybdenum pentachloride because the concentration of molybdenum pentachloride is the highest. In the middle of the structure to be deposited 110, the molybdenum film deposition and molybdenum pentachloride etching reach a balance because the concentration of molybdenum pentachloride is lower.

[0089] By controlling the number of sub-deposition cycles (S1-S4, S5-S8, and S9-S12), growth is achieved at the top, middle, and bottom of the high aspect ratio deposition structure 110, respectively. Under three combinations of molybdenum pentachloride concentrations and buffer cylinder pressures, molybdenum films can achieve uniform deposition on the surface, top, middle, and bottom of the high aspect ratio deposition structure 110, thereby obtaining a high step coverage.

[0090] While the above disclosure is provided, it is not limited thereto. Any person skilled in the art may make various alterations and modifications without departing from the spirit and scope of this disclosure; therefore, the scope of protection of this disclosure shall be determined by the scope defined in the claims.

Claims

1. A deposition method, characterized in that, include: Perform multiple sub-deposition cycles, each of which includes: Introduce the precursor; perform the first scavenging treatment; introduce the co-reactant; perform the second scavenging treatment; In each of the sub-deposition cycles, the concentration of the precursor introduced is different.

2. The deposition method as described in claim 1, characterized in that, The precursor has deposition and etching properties.

3. The deposition method as described in claim 2, characterized in that, The precursor is a halide.

4. The deposition method as described in claim 3, characterized in that, The precursor includes molybdenum pentachloride.

5. The deposition method as described in claim 1, characterized in that, The various sub-deposition cycles are carried out in order of increasing or decreasing concentration of the introduced precursor.

6. The deposition method as described in claim 1, characterized in that, In the step of introducing the precursor, a carrier gas is used to carry the precursor in order to introduce it. The concentration of the introduced precursor is different by adjusting the carrier gas flow rate and / or the carrier gas introduction time.

7. The deposition method as described in claim 6, characterized in that, The step of introducing the precursor includes: using a carrier gas to carry the precursor into a buffer cylinder; The precursor in the buffer cylinder is pulsed into the deposition chamber.

8. The deposition method as described in claim 7, characterized in that, In the step of pulsed precursor from the buffer cylinder into the deposition chamber, the pulse times of various sub-deposition cycles correspond to the same trend in the concentration of the precursor.

9. The deposition method as described in claim 1, characterized in that, The duration of the first scavenging treatment corresponds to the same trend in the concentration of the precursor.

10. The deposition method as described in claim 1, characterized in that, The deposition temperature of the sub-deposition cycle is 300°C to 500°C.

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