Process method and process equipment for thin film deposition

Abstract

The invention discloses a process method and process equipment for thin film deposition. The process method comprises the following steps: introducing a precursor into a substrate, wherein the surface of the substrate comprises a plurality of gaps; and sputtering gas is introduced, and first radio frequency energy is provided, so that the sputtering gas is dissociated into plasma to bombard the upper surface of the gap, the precursor on the upper surface of the gap is removed, and the amount of the precursor on the upper surface of the gap is smaller than the amount of the precursor in the gap. By executing the steps, the deposition rate of the upper surface of the gap can be reduced, but the deposition rate in the gap is not influenced, so that the step coverage rate in the gap can be enhanced and the gap filling capability in the deposition process can be improved under the condition of not increasing the reaction source consumption, the time length and the process complexity.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and in particular to a thin film deposition process method, a thin film deposition process equipment, and a computer-readable storage medium. Background Art

[0002] Traditional atomic layer deposition (ALD) technology has excellent gap filling ability due to its special "conformal growth" mechanism, which can achieve precise film thickness control in chip structures and step coverage in conventional structures. However, with the introduction of new chips, for special structures such as gaps with high aspect ratios, traditional ALD technology, and even plasma enhanced atomic layer deposition (PEALD) technology, cannot meet the high demand for seamless gap filling.

[0003] like Figure 1 As shown, for a gap 100 with a high aspect ratio, it usually means that the opening 110 of the gap 100 (such as a hole, a deep groove, a structure) is small and the space 120 inside it is large. Conventional ALD or PEALD deposition has a step coverage of 100%, and deposition will be based on the shape, which will cause the structure opening 110 to be closed in advance, and ultimately lead to the existence of a gap 121 inside the structure 120. Although the gap 121 inside the gap 100 with a high aspect ratio can be improved to a certain extent by simply increasing the amount of reaction sources, it will increase source consumption and purge time, thereby affecting production capacity.

[0004] At present, in order to improve the gap filling ability of the substrate structure, selective deposition can also be used to achieve precise deposition and removal of target materials at specified locations through specific chemical and material interactions. However, selective deposition requires the use of additional chemical sources, such as oxidants, to modify the substrate surface, and then remove the modified substrate surface, so that the reaction gas can be selectively deposited. This undoubtedly increases additional process costs and process operations, and may even require additional improvements to the equipment, increasing the complexity of the process.

[0005] In order to solve the above-mentioned problems existing in the prior art, the art urgently needs a thin film deposition process technology that can reduce the deposition rate on the upper surface of the gap without affecting the deposition rate inside the gap, thereby enhancing the step coverage inside the gap and improving the gap filling ability during the deposition process without increasing the reaction source consumption, time and process complexity. Summary of the invention

[0006] A brief summary of one or more aspects is given below to provide a basic understanding of these aspects. This summary is not an exhaustive overview of all conceived aspects, and is neither intended to identify the key or decisive elements of all aspects nor to define the scope of any or all aspects. Its only purpose is to give some concepts of one or more aspects in a simplified form as a prelude to a more detailed description that will be given later.

[0007] In order to overcome the above-mentioned defects of the prior art, the present invention provides a process method for thin film deposition, a process equipment for thin film deposition, and a computer-readable storage medium, which can reduce the deposition rate on the upper surface of the gap without affecting the deposition rate inside the gap, thereby enhancing the step coverage inside the gap and improving the gap filling ability during the deposition process without increasing the reaction source consumption, time and process complexity.

[0008] Specifically, the above-mentioned thin film deposition process method provided according to the first aspect of the present invention includes the following steps: introducing a precursor into a substrate, wherein the surface of the substrate includes a plurality of gaps; and introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap, so as to remove the precursor on the upper surface of the gap, so that the amount of the precursor on the upper surface of the gap is less than the amount of the precursor inside the gap.

[0009] Furthermore, in some embodiments of the present invention, the step of introducing sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into plasma to bombard the upper surface of the gap includes: introducing the sputtering gas and providing a first low-frequency radio frequency energy to dissociate the sputtering gas into a plasma with a first mean free path within a first time period, bombarding a first depth of the upper surface of the gap.

[0010] Furthermore, in some embodiments of the present invention, the step of introducing sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap includes: introducing the sputtering gas and providing a first high-frequency radio frequency energy to dissociate the sputtering gas into a plasma with a second mean free path within a second time period, bombarding a second depth of the upper surface of the gap, wherein the second time period is shorter than the first time period, the second mean free path is shorter than the first mean free path, and the second depth is shorter than the first depth.

[0011] Furthermore, in some embodiments of the present invention, the step of introducing sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into plasma to bombard the upper surface of the gap also includes: introducing the sputtering gas and providing a first radio frequency energy combining the low frequency and the high frequency to dissociate the sputtering gas into a plasma with a third mean free path within a third time period, bombarding a third depth of the upper surface of the gap, wherein the third time period is between the first time period and the second time period, the third mean free path is between the first mean free path and the second mean free path, and the third depth is between the first depth and the second depth.

[0012] Furthermore, in some embodiments of the present invention, after the step of introducing the precursor into the substrate, the process method further includes the following steps: in response to the precursor being adsorbed on the upper surface of the gap and inside the gap, introducing a purge gas into the substrate to remove excess precursor, wherein the purge gas includes a first inert gas, and the step of introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into plasma to bombard the upper surface of the gap includes: continuously introducing the first inert gas through the gas path of the purge gas, and providing a first radio frequency energy to dissociate the first inert gas into plasma to bombard the upper surface of the gap.

[0013] Furthermore, in some embodiments of the present invention, the step of introducing a sputtering gas and providing a first RF energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap also includes: obtaining a sputtering requirement of the upper surface of the gap; and closing the gas path of the purge gas, opening another gas path of an inert gas to introduce a second inert gas that meets the sputtering requirement, and starting the first RF energy to dissociate the second inert gas into a plasma to bombard the upper surface of the gap.

[0014] Furthermore, in some embodiments of the present invention, after the step of introducing sputtering gas and providing first radio frequency energy to dissociate the sputtering gas into plasma to bombard the upper surface of the gap, it also includes: introducing reaction gas and providing second radio frequency energy to react with the precursor on the upper surface of the gap and inside the gap to form a thin film; and introducing purge gas to remove reaction by-products.

[0015] Furthermore, in some embodiments of the present invention, the first inert gas includes any one or a combination of more of argon, helium and nitrogen, and the second inert gas includes any one or a combination of more of the argon, helium, nitrogen and hydrogen.

[0016] In addition, the above-mentioned thin film deposition process equipment provided according to the second aspect of the present invention includes: a reaction chamber, in which a substrate is placed; a first RF power supply, which provides a high-frequency first RF energy into the reaction chamber; a second RF power supply, which provides a low-frequency first RF energy into the reaction chamber; and a matcher, which connects the first RF power supply, the second RF power supply and the reaction chamber, and provides the first RF energy to the reaction chamber by turning on the first RF power supply and the first RF power supply separately or simultaneously, so as to perform the above-mentioned thin film deposition process method provided by the first aspect of the present invention.

[0017] In addition, according to the third aspect of the present invention, there is also provided a computer-readable storage medium on which computer instructions are stored. When the computer instructions are executed by a processor, the above-mentioned thin film deposition process method provided by the first aspect of the present invention is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above features and advantages of the present invention can be better understood after reading the detailed description of the embodiments of the present disclosure in conjunction with the following drawings. In the drawings, the components are not necessarily drawn to scale, and components with similar related properties or features may have the same or similar reference numerals.

[0019] Figure 1 A schematic diagram of a gap filling process of a high aspect ratio gap in the prior art is shown;

[0020] Figure 2 A flow chart of a thin film deposition process method provided according to some embodiments of the present invention is shown;

[0021] Figure 3 A schematic diagram of the process flow of PEALD in the prior art is shown;

[0022] Figure 4 A schematic diagram of a process flow of thin film deposition according to some embodiments of the present invention is shown;

[0023] Figure 5 A schematic diagram of a process flow of thin film deposition according to some other embodiments of the present invention is shown;

[0024] Figure 6 A schematic diagram of a process flow of thin film deposition according to some further embodiments of the present invention is shown;

[0025] Figure 7 A schematic diagram showing test results of process parameters provided according to some embodiments of the present invention is shown;

[0026] Fig. 8A A schematic diagram showing a gap filling process of a high aspect ratio gap provided in some embodiments of the present invention; and

[0027] Figure 8B A schematic diagram showing a gap filling result of a high aspect ratio gap provided according to an embodiment of the present invention is shown.

[0028] Reference numerals:

[0029] 100 Gap;

[0030] 110 Opening;

[0031] 120 internal;

[0032] 121 gap;

[0033] d spacing;

[0034] Steps S210 to S220;

[0035] Steps S221 to S223; and

[0036] Steps S310~S340. DETAILED DESCRIPTION

[0037] The following specific embodiments illustrate the implementation of the present invention, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this invention are limited to this implementation. On the contrary, the purpose of introducing the invention in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description.

[0038] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In addition, the terms "upper", "lower", "left", "right", "top", "bottom", "horizontal" and "vertical" used in the following description should be understood as the directions shown in the paragraph and the related drawings. Such relative terms are only used for the convenience of description and do not mean that the device described therein must be manufactured or operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0040] It is understood that although the terms "first", "second", "third", etc. may be used herein to describe various components, regions, layers and / or parts, these components, regions, layers and / or parts should not be limited by these terms, and these terms are only used to distinguish different components, regions, layers and / or parts. Therefore, the first component, region, layer and / or part discussed below may be referred to as a second component, region, layer and / or part without departing from some embodiments of the present invention.

[0041] As mentioned above, Figure 1 As shown, the step coverage of conventional ALD or PEALD deposition is 100%, and it will be deposited according to the shape, which will cause the structural opening 110 to be closed in advance, and ultimately cause the gap 121 to still exist inside the structure 120. Although the gap 121 inside the gap 100 with a high aspect ratio can be improved to a certain extent by simply increasing the amount of reaction source, it will increase source consumption and purge time, thereby affecting production capacity. At present, in order to improve the gap filling ability of the substrate structure, selective deposition can also be used to achieve precise deposition and removal of target materials at specified locations through specific chemical and material interactions. However, selective deposition requires the additional use of chemical sources, such as oxidants, to modify the substrate surface, and then remove the modified substrate surface, so that the reaction gas can be selectively deposited. This undoubtedly increases additional process costs and process operations, and may even require additional improvements to the equipment, increasing process complexity.

[0042] In order to solve the above-mentioned problems existing in the prior art, the present invention provides a process method for thin film deposition, a process equipment for thin film deposition, and a computer-readable storage medium, which can reduce the deposition rate on the upper surface of the gap without affecting the deposition rate inside the gap, thereby enhancing the step coverage inside the gap and improving the filling ability during the deposition process without increasing the reaction source consumption, time and process complexity.

[0043] In some non-limiting embodiments, the thin film deposition process provided by the first aspect of the present invention may be implemented by the thin film deposition process equipment provided by the second aspect of the present invention.

[0044] Specifically, in some non-limiting embodiments, the computer-readable storage medium provided in the third aspect of the present invention stores computer instructions, which, when executed by a processor, can be used to implement the thin film deposition process provided in the first aspect of the present invention.

[0045] The following will describe the various steps in the above-mentioned thin film deposition process method in conjunction with some embodiments of thin film deposition process equipment. Those skilled in the art will understand that these embodiments of thin film deposition process methods are only some non-limiting implementation methods provided by the present invention, which are intended to clearly demonstrate the main concept of the present invention and provide some specific solutions that are convenient for the public to implement, rather than to limit all working modes or all functions of the thin film deposition process equipment. Similarly, the thin film deposition process equipment is also only a non-limiting implementation method provided by the present invention, and does not constitute a limitation on the implementation subject of each step in these thin film deposition process methods.

[0046] In some embodiments of the present invention, the process equipment for thin film deposition may include a reaction chamber, in which a substrate may be placed to perform a thin film deposition process on the upper surface of the gap. Further, the process equipment for thin film deposition may cover two frequencies of RF power supplies at the same time. That is to say, the process equipment may also include a first RF power supply, which can be used to provide a first RF energy of high frequency to the reaction chamber, and a second RF power supply, which can be used to provide a first RF energy of low frequency to the reaction chamber. The first RF power supply, the second RF power supply and the reaction chamber are connected by a matcher (match box), and the first RF power supply or the first RF power supply can be turned on separately to provide the first RF energy of high frequency or low frequency to the reaction chamber for a process method of thin film deposition. In addition, the matcher can also turn on the first RF power supply and the second RF power supply at the same time to provide the reaction chamber with a first RF energy combining high frequency and low frequency for a process method of thin film deposition.

[0047] Next, see Figure 2 , Figure 2 A flow chart of a thin film deposition process method provided according to some embodiments of the present invention is shown.

[0048] There are multiple gaps in the three-dimensional upper surface of the substrate, such as deep holes, grooves, etc. During the thin film deposition process, it is usually necessary to completely fill the gaps on the surface of these substrates to form an electrical isolation layer, which is used as an insulating layer between circuits to mask the mutual diffusion and leakage of semiconductor core components, thereby further improving the reliability of semiconductor operating performance.

[0049] like Figure 2As shown, in some embodiments of the present invention, the process method for thin film deposition may include the following steps: step S210: introducing a precursor into a substrate; and step S220: introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap, so as to remove the precursor on the upper surface of the gap, so that the amount of precursor on the upper surface of the gap is less than the amount of precursor inside the gap.

[0050] First, please see Figure 3 , Figure 3 FIG. 2 shows a schematic diagram of the process flow of PEALD in the prior art. Figure 3 As shown, the conventional four-step film-forming reaction of PEALD includes, respectively, step S310: precursor introduction (dose); step S320: precursor purge (dose purge); step S330: RF on (RF on); and step S340: RF purge (RF purge).

[0051] In step S310, ALD precursors, such as bis(diethylamino)silane (BDEAS), diisopropylaminosilane (DIPAS), etc., can be introduced into the reaction chamber. At the same time, reaction gases, such as O2 or a mixture of N2O and O2, and purge gases such as Ar or N2 can also be introduced into the reaction chamber at the same time. Then, when executing step S320, the introduction of the precursor is stopped, and the purge gas can continue to enter the reaction chamber to remove excess reaction precursors and reaction by-products. Afterwards, step S330 can be executed to start the RF energy to convert the reaction precursor into a dense SiO film. Finally, step S340 can be executed to continue to introduce the purge gas to purge the reaction by-products in the chamber to ensure the cleanliness of the reaction chamber. The above steps S310 to S340 are one atomic layer deposition cycle.

[0052] On this basis, see Figure 4 , Figure 4 A schematic diagram of a process flow of thin film deposition provided according to some embodiments of the present invention is shown.

[0053] like Figure 4 As shown, step S210 is the same as step S310, and will not be described again. As for step S320, the embodiment of the present invention adopts step S220 to improve it. Specifically, step S220 can be embodied as steps S221-S222.

[0054] like Figure 4As shown, after step S210 is completed and the precursor has been adsorbed on the upper surface of the gap and inside the gap, step S221 can be performed to stop the introduction of the precursor and introduce a purge gas into the substrate in the reaction chamber to purge the precursor to remove excess precursor and reaction byproducts. Optionally, the purge gas can be a first inert gas.

[0055] Afterwards, step S222 may be performed, wherein the first inert gas is continuously introduced through the gas path of the purge gas, and the first radio frequency energy is provided, and a radio frequency reaction is generally performed for a certain period of time to dissociate the first inert gas into plasma to bombard the upper surface of the gap, thereby modifying the upper surface of the gap. Sputtering is performed to bombard the upper surface of the gap to remove the precursor physically / chemically adsorbed on the upper surface of the gap, so that the amount of precursor on the upper surface of the gap is less than the amount of precursor inside the gap, thereby reducing the deposition rate on the upper surface of the gap, and this process does not affect the deposition rate inside the gap. The "inside of the gap" here may at least include the sidewalls of the gap.

[0056] Alternatively, the first inert gas may include any one or a combination of more than one of argon, helium and nitrogen.

[0057] For example, in Figure 4 In the embodiment shown, the first inert gas used for purging is Ar. Therefore, during the sputtering step S222 after the purging work of step S221 is completed, the first inert gas Ar can continue to be introduced and the first inert gas Ar is used as the sputtering gas. Ar is electrolyzed by the first radio frequency energy to generate plasma to bombard the substrate surface. At the same time, during the execution of this step S222, the reaction gas including O2 (such as O2, or a mixed gas of N2O and O2) and the purging gas (such as N2) are stopped from being introduced.

[0058] Furthermore, since the sputtering effects of ions of different sputtering gases are different, different sputtering gases may be selected according to the sputtering requirements of the upper surface of the gap.

[0059] Specifically, see Figure 5 , Figure 5 A schematic diagram of a process flow of thin film deposition provided according to some other embodiments of the present invention is shown.

[0060] like Figure 5 As shown, in some other embodiments of the present invention, step S210 is the same as step S310, and step S221 has been introduced above and will not be repeated here. In this embodiment, the above step S222 can be replaced by step S223.

[0061] Specifically, if Figure 5As shown, the sputtering requirement of the upper surface of the gap can be obtained first. Then, step S223 is executed, the gas path of the purge gas is closed, and the gas path of another inert gas is opened to introduce a second inert gas that meets the sputtering requirement, and the first RF energy is started, and the RF reaction is generally performed for a certain period of time to dissociate the second inert gas into plasma to bombard the upper surface of the gap, thereby modifying the upper surface of the gap. By introducing the plasma of the second inert gas to bombard the upper surface of the gap, it is used to remove the precursor physically / chemically adsorbed on the upper surface of the gap, so that the amount of precursor on the upper surface of the gap is less than the amount of precursor inside the gap, thereby reducing the deposition rate on the upper surface of the gap, and this process does not affect the deposition rate inside the gap.

[0062] Optionally, the second inert gas may include any one or a combination of argon, helium, nitrogen and hydrogen. Since the first inert gas is also used as a purge gas, the first inert gas used as a purge does not include the active gas hydrogen. However, since there are great differences between the plasmas of active gases and hydrogen has its own special reducing properties, the second inert gas used only for sputtering may include hydrogen.

[0063] For example, in Figure 5 In the embodiment shown, the purge gas used for purging can be Ar (or N2). Therefore, during the sputtering step S223 after the purging work of step S221 is completed, the gas path of the purge gas Ar (or N2) can be closed, and the gas path of the second inert gas He can be opened at the same time, and the second inert gas He is used as the sputtering gas. He is electrolyzed by the first radio frequency energy to generate plasma to bombard the substrate surface. In addition, during the execution of this step S223, the reaction gas including O2 (such as O2, or a mixed gas of N2O and O2) and the purge gas (such as Ar, N2) are stopped from being introduced.

[0064] According to the above Figure 4 and Figure 5 As shown, in the sputtering step, according to the sputtering requirements of the upper surface of the gap, the purge gas path can be continuously opened to continuously introduce an inert purge gas (such as Ar) as a sputtering gas for electrolysis, or it can be switched to another gas path, and another inert gas (such as He) different from the purge gas can be selected as the sputtering gas for electrolysis. Optionally, it can also be switched to another gas path, but the other gas path can still introduce the same inert gas (such as Ar) as the purge gas as the sputtering gas for electrolysis. The switching can be performed by setting the process parameters (recipe) in semiconductor manufacturing.

[0065] In the above-mentioned embodiment of the present invention, when performing the sputtering process of steps S222 and S223, it is necessary to stop the introduction of the reaction gas including O2. The reason is that if oxygen is introduced during the sputtering process, the oxygen will react with the precursor remaining on the surface and form a thin film, and this phenomenon will significantly reduce the sputtering effect. Therefore, the sputtering gas in the present invention is not suitable for selecting a gas that reacts with the precursor to form a thin film, such as O2. Nitrogen, helium, argon, etc. are inert gases, and the plasma generated after ionization will not chemically react with the precursor on the substrate, and the plasma of hydrogen has a strong reducing property and will not chemically react with the precursor on the substrate. Therefore, optionally, the sputtering gas used for sputtering may include but is not limited to one or more of argon, helium, nitrogen, and hydrogen.

[0066] For further information, see Figure 6 , Figure 6 A schematic diagram of a process flow of thin film deposition provided according to some further embodiments of the present invention is shown.

[0067] like Figure 6 As shown, in some optional embodiments, in order to shorten the process time, the Figure 4 or Figure 5 Step S221 in step S220, that is, after step S210, directly execute step S220, introduce sputtering gas, and provide first RF energy, generally initiate RF reaction for a certain period of time to dissociate the sputtering gas into plasma to bombard the upper surface of the gap, modify the upper surface of the gap, and thus further shorten the process time. Similarly, by bombarding the upper surface of the gap by sputtering, the precursor (precursor) physically / chemically adsorbed on the upper surface of the gap is removed, so that the amount of precursor on the upper surface of the gap is less than the amount of precursor inside the gap, thereby reducing the deposition rate on the upper surface of the gap, and this process does not affect the deposition rate inside the gap.

[0068] Furthermore, in some preferred embodiments, Figure 4 or Figure 5 As shown, in the sputtering process of the above step S222 or step S223, after the sputtering gas is introduced, the first radio frequency energy provided to the reaction chamber can be low-frequency radio frequency energy. Since the mean free path of ions is greater at low frequencies than at high frequencies, the energy generated by ions will also increase, and the sputtering effect will be more obvious. In addition, low frequencies can also enable ions to reach deeper into the gap. Therefore, in this embodiment, the sputtering gas can be dissociated into a plasma with a first mean free path within a first time period, bombarding the first depth of the upper surface of the gap.

[0069] In other optional embodiments, during the sputtering process of step S222 or step S223, after the sputtering gas is introduced, the first radio frequency energy provided to the reaction chamber may be high-frequency radio frequency energy. Since the sputtering gas is more easily dissociated to form plasma at high frequencies, the gas dissociation time is shorter and the dissociation is more efficient. In this embodiment, the sputtering gas may be dissociated into a plasma of a second mean free path within a second time period, bombarding a second depth of the upper surface of the gap, wherein the second time period may be less than the first time period, the second mean free path may be less than the first mean free path, and the second depth may be less than the first depth.

[0070] Further, in some other optional embodiments, during the sputtering process of step S222 or step S223, after the sputtering gas is introduced, the first RF energy provided to the reaction chamber can be a RF energy combining low frequency and high frequency. Since the process equipment for thin film deposition can simultaneously include a RF power supply of logn frequency, a first RF power supply providing a high frequency and a second RF power supply providing a low frequency, after the two RF power supplies are simultaneously turned on through a matcher, during the sputtering process of step S222 or step S223, after the high frequency and low frequency RF energies are combined, the above advantages of the two frequencies can be achieved, and different frequencies can be suitable for different process requirements.

[0071] Afterwards, if Figure 4 or Figure 5 or Figure 6 As shown, the thin film deposition process method of the present invention may further include step S230: introducing a reaction gas and providing a second radio frequency energy to react with the precursor on the upper surface of the gap and inside the gap to form a thin film.

[0072] Specifically, in some embodiments, a reaction gas including O2, such as a mixed gas of O2 or N2O and O2, may be introduced, and then a second RF energy may be provided into the reaction chamber to cause the reaction gas adsorbed on the upper surface of the gap and the precursor inside the gap to react, thereby generating a dense SiO film.

[0073] Optionally, the second RF energy provided in step S230 may be lower than or equal to the first RF energy provided in step S220. Figure 4 or Figure 5 or Figure 6 As shown in , the second RF energy may also be higher than the first RF energy in step S220.

[0074] Afterwards, if Figure 4 or Figure 5 or Figure 6As shown in , step S240 may be executed: performing radio frequency purge operation to continue to purge excess reaction gas and reaction by-products in the reaction chamber to ensure cleanliness in the reaction chamber.

[0075] Next, see Figure 7 , Figure 7 A schematic diagram showing test results of process parameters provided according to some embodiments of the present invention is shown.

[0076] like Figure 7 As shown, in some embodiments of the present invention, the deposition results on the upper surface of the gap obtained by different thin film deposition process methods are tested. In the first test, the traditional PEALD technology is used, which does not include a sputtering step (the sputtering time column corresponds to 0). Specifically, in step S310, the precursor is introduced, and optionally, the duration of the precursor introduction can be 0.5s. Then step S320 is executed to purge the precursor. Optionally, the duration of the precursor purge can be 0.5s, and then step S330 is executed to turn on the radio frequency to provide a second radio frequency energy to convert the precursor into a dense film. Optionally, the radio frequency turn-on time can be 0.5s, and the second radio frequency energy can be 500W. Finally, step S340 is executed to perform radio frequency purge. Optionally, the duration of radio frequency purge can be 0.5s. Finally, in the first test, the film thickness generated on the upper surface of the substrate is Since conventional PEALD deposition can achieve 100% step coverage, the film thickness on the gap surface and the sidewall inside the gap is

[0077] In the second test example, steps S210, S230, and S240 are the same as S310, S330, and S340 in the first test, and will not be repeated here, while step S220 is different from step S320 in the first test. In the second test example, an Ar sputtering step is added to step S220, but the first RF energy is not provided during the sputtering process. In addition, in order not to increase the overall duration of the process, optionally, during the precursor purge process of step S221, the precursor purge time can be shortened to 0.1s. After that, Ar sputtering is performed for 1s. Finally, the film thickness generated on the upper surface of the substrate is slightly improved, but the improvement effect is not obvious. The film thickness on the upper surface of the gap is reduced to

[0078] Continue as Figure 7 As shown, in the third, fourth and fifth test examples, an Ar sputtering step is added to step S220, and first RF energies of different frequencies are provided during the sputtering process. And since steps S210, S230, and S240 are the same as the corresponding steps in the first test, they are not repeated here. Similarly, step S220 is different from the above step S320.

[0079] Specifically, in the third test example, during the Ar sputtering step, only the first RF energy of 400W high frequency was provided. In the fourth test example, during the Ar sputtering step, the first RF energy of 400W high frequency and 300W low frequency was provided at the same time. And in the fifth test example, during the Ar sputtering step, the first RF energy of 400W high frequency and 600W low frequency was provided at the same time. The film thickness on the upper surface of the substrate obtained in the third test example, the fourth test example and the fifth test example obviously decreased gradually, from Further reduced to

[0080] According to the above Figure 7 In the second to fourth test examples, it can be seen through the bare silicon substrate that bombarding the adsorbed reaction sources through the sputtering step and knocking them off the adsorption can weaken the physical or chemical adsorption of the reaction sources on the upper surface of the gap, thereby reducing the film thickness on the upper surface of the gap, that is, reducing the deposition rate on the upper surface of the gap.

[0081] Those skilled in the art will appreciate that the above Figure 7 The execution time of each step, as well as the parameters such as the magnitude of the first RF energy and the second RF energy provided, are only a non-limiting implementation method provided by the present invention, which is intended to clearly demonstrate the main concept of the present invention and provide a specific solution that is convenient for the public to implement, rather than to limit the scope of protection of the present invention. Optionally, in other embodiments, those skilled in the art can also determine according to the specific process based on the concept of the present invention to achieve the same technical effect.

[0082] Please see Fig. 8A , Fig. 8A A schematic diagram of a gap filling process for a high aspect ratio gap provided according to some embodiments of the present invention is shown.

[0083] like Fig. 8A As shown, the left figure can correspond to Figure 7 In the first test case, the conventional PEALD process makes the ratio of the film thickness h1 on the top surface to the film thickness h2 on the gap sidewall 1:1, that is, the film thickness in the two regions is the same. Further, Fig. 8A The right picture in the figure can correspond to Figure 7 In the second to fifth test examples, due to the introduction of the sputtering process, the sidewall inside the gap can maintain the original growth rate, while the film thickness on the upper surface of the gap can be reduced, that is, the ratio of the film thickness h1' on the upper surface to the film thickness h2' on the sidewall of the gap h1':h2' can be less than 1:1. Optionally, the film thickness h1' on the upper surface can be reduced to 94% of the original growth rate.

[0084] Furthermore, in the fifth test, by adding the first RF energy combining 400W low frequency and 600W high frequency, the inner sidewall of the gap can maintain the original growth rate while the film thickness on the upper surface of the gap is only 91% of the original growth rate.

[0085] For further information, see Figure 8B , Figure 8B A schematic diagram showing gap filling results of a high aspect ratio gap provided according to some embodiments of the present invention is shown.

[0086] like Figure 8B As shown in FIG. 1 , in a specific embodiment of the present invention, the deposition mode with high step coverage can increase the thickness of the sidewall film, thereby reducing the spacing d between the sidewalls inside the gap to 50%, indicating that the original high aspect ratio gap has been filled before the top is sealed. Since the growth rate of the sidewall inside the gap is greater than the growth rate of the upper surface (top) of the gap, the premature sealing of the opening can be slowed down, and finally the gap is removed. Figure 1 The gap 121 in the gap 100 is shown in FIG. Therefore, the thin film growth mode brought about by the thin film deposition process provided by the present invention can prevent the gap from forming a gap inside after the gap is sealed.

[0087] Although the above methods are illustrated and described as a series of actions for simplicity of explanation, it should be understood and appreciated that these methods are not limited by the order of the actions, because according to one or more embodiments, some actions may occur in a different order and / or concurrently with other actions from those illustrated and described herein or not illustrated and described herein but understandable to those skilled in the art.

[0088] Those skilled in the art will further appreciate that the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, in a software module executed by a processor, or in a combination of the two. The software module may reside in a RAM memory, a flash memory, a ROM memory, an EPROM memory, an EEPROM memory, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor so that the processor can read and write information from / to the storage medium. In an alternative, a storage medium may be integrated into a processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In an alternative, the processor and the storage medium may reside in a user terminal as discrete components.

[0089] In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented as a computer program product in software, each function may be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Computer-readable media include both computer storage media and communication media, including any medium that facilitates the transfer of a computer program from one place to another. Storage media may be any available medium that can be accessed by a computer. As an example and not limitation, such a computer-readable medium may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or any other medium that can be used to carry or store the desired program code in the form of an instruction or data structure and can be accessed by a computer. Any connection is also properly referred to as a computer-readable medium. For example, if the software is transmitted from a website, a server, or other remote source using a coaxial cable, a fiber optic cable, a twisted pair, a digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwaves, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwaves are included in the definition of the medium. Disk and disc as used herein include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc, wherein disk often reproduces data magnetically, while disc reproduces data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0090] In summary, the present invention provides a process method for thin film deposition, a process equipment for thin film deposition, and a computer-readable storage medium, which can reduce the deposition rate on the upper surface of the gap without affecting the deposition rate inside the gap, thereby enhancing the step coverage inside the gap and improving the filling ability during the deposition process without increasing the reaction source consumption, time and process complexity.

[0091] The previous description of the disclosure is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other variations without departing from the spirit or scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A thin film deposition process, characterized in that: The following steps are involved: Passing a precursor into a substrate, wherein a surface of the substrate includes a plurality of gaps; as well as Sputtering gas is introduced and first radio frequency energy is provided to dissociate the sputtering gas into plasma to bombard the upper surface of the gap, so as to remove the precursor on the upper surface of the gap, so that the amount of precursor on the upper surface of the gap is less than the amount of precursor inside the gap.

2. The process according to claim 1, characterized in that: The step of introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap comprises: The sputtering gas is introduced and a low-frequency first radio frequency energy is provided to dissociate the sputtering gas into a plasma with a first mean free path within a first time period to bombard a first depth of the upper surface of the gap.

3. The process according to claim 2, characterized in that: The step of introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap comprises: The sputtering gas is introduced and a high-frequency first radio frequency energy is provided to dissociate the sputtering gas into a plasma with a second mean free path within a second time period to bombard a second depth of the upper surface of the gap, wherein the second time period is shorter than the first time period, the second mean free path is shorter than the first mean free path, and the second depth is shorter than the first depth.

4. The process according to claim 3, characterized in that: The step of introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap also includes: The sputtering gas is introduced and a first radio frequency energy combining the low frequency and the high frequency is provided to dissociate the sputtering gas into a plasma with a third mean free path within a third time period to bombard a third depth of the upper surface of the gap, wherein the third time period is between the first time period and the second time period, the third mean free path is between the first mean free path and the second mean free path, and the third depth is between the first depth and the second depth.

5. The process according to claim 1, characterized in that: After the step of introducing the precursor into the substrate, the process method further comprises the following steps: in response to the precursor being adsorbed on the upper surface of the gap and inside the gap, introducing a purge gas into the substrate to remove excess of the precursor, wherein the purge gas comprises a first inert gas, The step of introducing sputtering gas and providing first radio frequency energy to dissociate the sputtering gas into plasma to bombard the upper surface of the gap includes: continuously introducing the first inert gas through the gas path of the purge gas and providing first radio frequency energy to dissociate the first inert gas into plasma to bombard the upper surface of the gap.

6. The process according to claim 5, characterized in that: The step of introducing a sputtering gas and providing a first radio frequency energy to dissociate the sputtering gas into a plasma to bombard the upper surface of the gap also includes: Obtaining a sputtering requirement of an upper surface of the gap; and The gas path of the purge gas is closed, and another gas path of the inert gas is opened to introduce a second inert gas that meets the sputtering requirement, and the first radio frequency energy is started to dissociate the second inert gas into plasma to bombard the upper surface of the gap.

7. The process according to claim 5, characterized in that: After the step of introducing the sputtering gas and providing the first radio frequency energy to dissociate the sputtering gas into plasma to bombard the upper surface of the gap, the method further includes: Passing a reaction gas and providing a second radio frequency energy to react with the precursor on the upper surface of the gap and inside the gap to form a thin film; and A purge gas is introduced to remove reaction by-products.

8. The process according to claim 6, characterized in that: The first inert gas includes any one or a combination of argon, helium, and nitrogen, and the second inert gas includes any one or a combination of the argon, helium, nitrogen, and hydrogen.

9. A process equipment for thin film deposition, characterized in that: include: a reaction chamber, in which a substrate is placed; A first radio frequency power supply, providing high-frequency first radio frequency energy into the reaction chamber; a second radio frequency power supply, providing low-frequency first radio frequency energy into the reaction chamber; as well as A matcher is provided, connecting the first RF power supply, the second RF power supply and the reaction chamber, and providing the first RF energy to the reaction chamber by turning on the first RF power supply and the second RF power supply separately or simultaneously, so as to perform the process method for thin film deposition as described in any one of claims 1 to 8.

10. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the thin film deposition process method according to any one of claims 1 to 8 is implemented.

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