Topography-selective and area-selective ALD using fluorocarbon barrier layers

Abstract

A method for selectively depositing a film comprises: a) placing a substrate in a process chamber. The substrate comprises a first material and a second material, wherein the first material is exposed and comprises silicon oxide (SiO z ), the second material is exposed and is selected from silicon (Si) and silicon nitride (Si x N y ), wherein z, x and y are numbers defining a chemical ratio of elements. The method comprises: b) supplying a first gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the substrate; d) removing the first gas mixture from the process chamber; e) supplying an inert gas mixture and energizing a plasma for a second predetermined period of time to perform an activation step; and f) removing the inert gas mixture from the process chamber.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 62 / 650,351, filed on March 30, 2018. The entire disclosures of the above-referenced applications are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to substrate processing systems, and more particularly to substrate processing systems for selectively depositing dielectric or metal films using a fluorocarbon stop layer. Background Art

[0004] The background description provided here is for the purpose of generally presenting the context of the present disclosure. The work of the presently designated inventors is neither explicitly nor implicitly admitted to be prior art against the present disclosure to the extent that it is described in this background section and in aspects of the description that could not be determined as prior art at the time the application was filed.

[0005] Substrate processing systems have been used to deposit, etch, ash, clean, or otherwise process films on substrates (e.g., semiconductor wafers). For example, atomic layer deposition (ALD) can be used to deposit a monolayer on a substrate. During ALD, a substrate is placed in a processing chamber and exposed to a precursor gas for a predetermined period of time. The processing chamber is purged. Then, the substrate is exposed to a reactant gas for a predetermined period of time, and the processing chamber is purged. The ALD process can be repeated one or more times to deposit additional monolayers.

[0006] In some processes, dielectric or metal films need to be selectively deposited on silicon dioxide (SiO2 or SiO x ) film without depositing the film on exposed silicon (Si) or silicon nitride (identified here as Si3N4 or SiN) on the substrate. Current processes require photolithography and patterning to produce a selective film only on one type of exposed surface, which is a top-down etching method. However, it is desirable to have a bottom-up deposition method rather than a top-down etching method to minimize the complexity and cost of the patterning step and reduce edge placement errors. Summary of the invention

[0007] A method for selectively depositing a film comprises: a) placing a substrate in a process chamber. The substrate comprises a first material and a second material, wherein the first material is exposed and comprises silicon oxide (SiO z ), the second material is exposed and is selected from silicon (Si) and silicon nitride (Si x N y), wherein z, x and y are numbers defining chemical ratios of elements. The method comprises: b) supplying a first gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the substrate; d) removing the first gas mixture from the process chamber; e) supplying a second gas mixture and energizing a plasma for a second predetermined period of time to perform an activation step; and f) removing the second gas mixture from the process chamber.

[0008] In other features, the activating step preferentially removes the fluorocarbon layer on the first material over the fluorocarbon layer on the second material. The method includes: g) repeating b) through f) N times, where N is an integer; and h) depositing a film on the first material and substantially preventing film deposition on the second material using the fluorocarbon layer.

[0009] In other features, the activating step preferentially removes the fluorocarbon layer on the sidewalls of the substrate compared to the fluorocarbon layer on the planar surface of the substrate. The method includes: g) repeating b) through f) N times, where N is an integer; and h) depositing a film on the sidewalls and substantially preventing the film from being deposited on the planar surface using the fluorocarbon layer.

[0010] In other features, the activating step preferentially removes the fluorocarbon layer on the planar surface of the substrate compared to the fluorocarbon layer on the sidewalls of the substrate. The method includes: g) repeating b) through f) N times, where N is an integer; and h) depositing a film on the planar surface and substantially preventing the film from being deposited on the sidewalls using the fluorocarbon layer.

[0011] In other features, the method includes: g) repeating b) to f) N times, where N is an integer; and h) selectively depositing a film on the substrate and substantially preventing the film from being deposited on the substrate using a fluorocarbon layer.

[0012] In other features, the first gas mixture comprises a gas selected from the group consisting of fluorocarbon gases (C a F b ), hydrocarbon gas (H c C d ), hydrofluorocarbon gases (C e F f H g), molecular hydrogen gas (H2) and a combination thereof, wherein a, b, c, d, e, f and g are numbers defining the chemical ratio of the elements. The first gas mixture further comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar). The second gas mixture comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

[0013] In other features, h) includes performing atomic layer deposition (ALD). The method also includes, after g) and before h): g1) supplying a third gas mixture including an oxygen species; and g2) exciting the plasma for a predetermined period of time. The method also includes: g3) repeating a) to g2) one or more times.

[0014] In other features, the third gas mixture comprises one or more gases selected from the group consisting of molecular oxygen (O2), ozone (O3), water (H2O), carbon dioxide (CO2), carbon monoxide (CO) and nitrous oxide (N2O). The predetermined time period is in the range from 0.5 seconds to 30 seconds.

[0015] In other features, the substrate includes a first silicon dioxide layer, a silicon nitride layer disposed above the first silicon dioxide layer, and a second silicon dioxide layer disposed above the silicon nitride layer. The fluorocarbon layer is selectively deposited on sidewalls of the silicon nitride layer and the second silicon dioxide layer. The film is selectively deposited on planar regions of the first silicon dioxide layer and the second silicon dioxide layer and is substantially stopped by the fluorocarbon layer on the sidewalls of the silicon nitride layer and the second silicon dioxide layer.

[0016] In other features, the substrate includes a first silicon nitride layer, a silicon dioxide layer disposed above the first silicon nitride layer, and a second silicon nitride layer disposed above the silicon dioxide layer. The fluorocarbon layer is selectively deposited on sidewalls of the silicon dioxide layer and the second silicon nitride layer. The film is deposited on planar areas of the first silicon nitride layer and the second silicon nitride layer and is substantially stopped by the fluorocarbon layer on the sidewalls of the silicon dioxide layer and the second silicon nitride layer.

[0017] In other features, the substrate includes a first silicon dioxide layer, a silicon nitride layer disposed above the first silicon dioxide layer, and a second silicon dioxide layer disposed above the silicon nitride layer. The fluorocarbon layer is selectively deposited on planar surfaces of the first silicon dioxide layer and the second silicon dioxide layer. The film is deposited on sidewalls of the silicon nitride layer and the second silicon dioxide layer and is substantially stopped by the fluorocarbon layer on the planar surfaces of the first silicon dioxide layer and the second silicon dioxide layer.

[0018] In other features, the substrate includes a first silicon nitride layer, a silicon dioxide layer disposed over the first silicon nitride layer, and a second silicon nitride layer disposed over the silicon dioxide layer. The fluorocarbon layer is selectively deposited on planar surfaces of the first silicon nitride layer and the second silicon nitride layer. The film is deposited on the sidewalls of the silicon dioxide layer and the second silicon nitride layer and is substantially stopped by the fluorocarbon layer on the planar surfaces of the first silicon nitride layer and the second silicon nitride layer.

[0019] In other features, the film includes an ALD dielectric layer. The film includes an ALD metal layer.

[0020] A method for selectively depositing a film comprises: a) placing a substrate in a process chamber. The substrate comprises silicon oxide (SiO z ) and a first exposed material selected from silicon (Si) and silicon nitride (Si x N y ), wherein z, x, and y are numbers defining chemical ratios of elements. The method further comprises: b) supplying a gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the substrate; d) removing the gas mixture from the process chamber; e) performing ion bombardment to remove a portion of the fluorocarbon layer from a planar portion of the substrate; and f) selectively depositing a film on the planar portion of the substrate and substantially preventing the film from being deposited on a sidewall of the substrate using the fluorocarbon layer.

[0021] In other features, the gas mixture comprises a gas selected from the group consisting of fluorocarbon gases (C a F b ), hydrocarbon gas (H c C d ), hydrofluorocarbon gases (C e F f H g ), molecular hydrogen gas (H2), and combinations thereof, wherein a, b, c, d, e, f, and g are numbers defining the chemical ratios of the elements.

[0022] In other features, the gas mixture further comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr), and argon (Ar). f) comprises performing atomic layer deposition (ALD). The film comprises an ALD dielectric layer. The film comprises an ALD metal layer.

[0023] A method for selectively depositing a film comprises: a) placing a substrate in a process chamber. The substrate comprises silicon oxide (SiO z ) and a first exposed material selected from silicon (Si) and silicon nitride (Si x N y ), wherein z, x and y are numbers defining the chemical ratio of the elements. The method comprises: b) supplying a first gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) exciting a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the second exposed material of the substrate; d) removing the gas mixture from the process chamber; e) depositing a film on the first exposed material using atomic layer deposition; f) removing reactants from the process chamber; g) repeating the depositing of the fluorocarbon layer in b) to e) and the depositing of the film in e) and f) one or more times to deposit the film on the first exposed material without causing the film to mushroom.

[0024] In other features, the gas mixture comprises a gas selected from the group consisting of fluorocarbon gases (C a F b ), hydrocarbon gas (H c C d ), hydrofluorocarbon gases (C e F f H g ), molecular hydrogen gas (H2) and a combination thereof, wherein a, b, c, d, e, f and g are numbers defining the chemical ratio of the elements. The gas mixture comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

[0025] A method for selectively depositing a film comprises: a) placing a substrate in a process chamber. The substrate comprises silicon oxide (SiO z ) and a first exposed material selected from silicon (Si) and silicon nitride (Si x N y), wherein z, x and y are numbers defining chemical ratios of elements. The method comprises: b) supplying a first gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the second exposed material of the substrate; d) removing the gas mixture from the process chamber; e) depositing a film on the first exposed material using atomic layer deposition; f) removing reactants from the process chamber; g) supplying a second gas mixture and energizing a plasma for a second predetermined period of time to perform an activation step; and h) removing the inert gas mixture from the process chamber.

[0026] In other features, the activating step preferentially removes the fluorocarbon layer on the first material over the fluorocarbon layer on the second material. The method comprises repeating at least one of the following: depositing the fluorocarbon layer in b) to d); depositing the film in e) and f); and the activating steps in g) and h). The activating steps in g) and h) are used to remove nucleation defects in the fluorocarbon layer. The second gas mixture further comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr), and argon (Ar).

[0027] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0029] Figure 1 According to the present disclosure, the use of advanced mixed mode pulse modulation (AMMP) TM ) process, a graph showing an example of the relationship between the thickness of a planar SiN, a planar SiO2 and a fluorocarbon (referred to as FC) film on the sidewall surface as a function of time during the deposition (D), activation (A) and oxygen flash steps performed by the process;

[0030] FIG. 2A to FIG. 2D is a side cross-sectional view of an example of a substrate during selective ALD using a FC stop layer according to the present disclosure;

[0031] Figure 3A and Figure 3B is a side cross-sectional view of an example of a substrate during selective ALD using a FC stop layer and defect removal or repair according to the present disclosure;

[0032] FIG. 4A to FIG. 4C is a side cross-sectional view of a substrate during selective ALD using a FC stop layer and preventing mushrooming during ALD deposition according to the present disclosure;

[0033] FIG. 5A to FIG. 5C is a side cross-sectional view of an example of a substrate during deposition of a FC stop layer on a sidewall according to the present disclosure;

[0034] FIG. 6A to FIG. 6E is a side cross-sectional view of a substrate during deposition of a FC stop layer according to an example of the present disclosure;

[0035] Figure 7 is a graph showing an example of FC film thickness as a function of time on planar SiN, planar SiO2, and sidewall surfaces using fewer deposition and activation steps between oxygen flash steps in accordance with the present disclosure;

[0036] Fig. 8A and Figure 8B is a side cross-sectional view of an example of a substrate during selective ALD on sidewalls using a FC stop layer on a planar surface according to the present disclosure;

[0037] Fig.9A and Fig. 9B is a side cross-sectional view of an example of a substrate during selective ALD on the sidewalls using a FC stop layer on a flat area according to the present disclosure;

[0038] Fig.10 is a graph showing an example of FC film thickness as a function of time on sidewalls, planar SiN, planar SiO2 surfaces for a process with fewer oxygen flash steps according to the present disclosure;

[0039] Fig.11A and Fig. 11B is a side cross-sectional view of a substrate during selective ALD on a flat area using a FC stop layer on the sidewalls according to the present disclosure;

[0040] FIG. 12A to FIG. 12B is a side cross-sectional view of a substrate during selective ALD on a flat area using a FC stop layer on the sidewalls according to the present disclosure;

[0041] FIG. 13A to FIG. 13C is a side cross-sectional view of a substrate during ALD using a FC stop layer and bombarding a planar region with ions according to an example of the present disclosure;

[0042] Figures 14 to 16 is a flow chart illustrating an exemplary method according to the present disclosure.

[0043] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0044] Systems and methods according to the present disclosure are useful for using fluorocarbons (CF x , referred to as FC) polymer barrier layer to selectively deposit dielectric or metal films. The systems and methods described herein are relatively simple to manufacture with respect to surfaces based primarily on silicon nitride (Si x N y , where x and y are numbers defining the chemical ratios of the elements or SiN) or silicon (Si) surfaces, for surfaces based primarily on silicon oxide (SiO x ) surface. x and Si x N y It refers to the fact that a small amount of H or C or H, C or O may also exist in the film. x Selectively depositing dielectric or metal films on substrates is challenging due to the similar surface chemistry between these materials.

[0045] After depositing the FC stop layer, ALD of the metal film or dielectric film is performed. In some examples, the FC stop layer slows down or substantially stops ALD nucleation on the SiN and / or Si surface, while the SiO x Growth on the surface is relatively uninhibited. As used herein, substantially preventing can refer to preventing more than 90%, 95%, or 99% of deposition from occurring at other locations not prevented by the FC stop layer. After ALD, the FC stop layer can be removed immediately or after further substrate processing.

[0046] The systems and methods described herein can also support topographically selective growth, where growth occurs on planar (or horizontal) surfaces but not on vertical sidewalls, or vice versa. For example, a FC stop layer can be deposited on both planar and vertical surfaces, and then selectively removed from the planar surfaces relative to the sidewalls using ion bombardment that primarily impinges on the planar surfaces. The FC stop layer remains on the sidewalls, thereby enabling selective ALD of films on planar regions of the substrate.

[0047] Alternatively, the FC stop layer can be selectively deposited on the flat areas of Si or SiN. The process can be adjusted so that the FC deposition rate on the flat surface is greater relative to the sidewalls. The thinner sidewall FC deposits can be completely removed by flash plasma, which means exciting the plasma with an oxygen-containing species for a very short pulse time, such as molecular oxygen (O2) or a mixture of oxygen (O2) and hydrogen (H2), or a mixture of oxygen (O2) and an inert gas such as argon (Ar), helium (He), nitrogen (N2), xenon (Xe) and krypton (Kr). The FC stop layer remains at the thicker flat surface, thereby enabling preferential ALD on the sidewalls. In some examples, the flash oxygen plasma is maintained for a predetermined time period in the range of 0.5 seconds to 30 seconds. In some examples, the oxygen-containing species is selected from the group consisting of molecular oxygen (O2), ozone (O3), water (H2O), carbon dioxide (CO2), carbon monoxide (CO) and nitrous oxide (N2O).

[0048] In some examples, the FC-blocking layer is deposited by providing a gas mixture comprising a fluorocarbon species and a hydrogen species. In some examples, the gas mixture includes a fluorocarbon gas (C x F y ), hydrocarbon gas (H x C y ), hydrofluorocarbon gases (C x F y H z ), molecular hydrogen gas (H2), and / or combinations thereof. In some examples, an inert gas such as argon, helium, molecular nitrogen (N2), xenon (Xe), and krypton (Kr) is also added to the gas mixture. In some examples, the deposition is performed in an inductively coupled plasma (ICP) substrate processing system. In some examples, the deposition is performed in a transformer coupled plasma (TCP) substrate processing system. In some examples, the substrate processing system further includes an electrostatic chuck (ESC) that can apply an RF bias to enhance ion bombardment. The plasma is energized for a predetermined deposition time period. The FC stop layer is deposited on the SiO x , SiN and / or Si surfaces.

[0049] After deposition, an activation step may be used to remove SiO from the SiN and / or Si surface. x The FC blocking layer is selectively or preferentially removed from the surface. In some examples, the activation step includes using a plasma containing argon (Ar) or helium (He). Repeated cycles of the FC deposition step, the activation step, and / or the oxygen flash step and their corresponding processing cycles determine where the FC blocking layer remains on the substrate before the ALD step.

[0050] If ALD is needed on the sidewalls, oxygen flash is used (using a plasma containing an oxygen species). In some examples, the oxygen plasma is pulsed using RF pulse modulation and / or RF continuous wave (CW) is used to remove thinner FC sidewall buildup. The oxygen flash step removes FC from all surfaces, including planar surfaces and sidewall surfaces. If you start with a thinner FC layer on the sidewalls, the sidewall surfaces will be removed, while some FC remains on the planar surfaces.

[0051] As will be further described below, different effects can be achieved by changing process parameters such as the relative number of FC deposition and activation steps, the duration of the deposition or activation cycle, the duration and frequency of the oxygen flash, and process parameters such as the RF power or the magnitude of the ESC bias or process pressure during deposition, activation oxygen flash steps, etc.

[0052] An example of the deposition of a FC blocking layer and the use of Ar activation is shown and described in "Surface Phenomena During Plasma-Assisted Atomic Layer Etching of SiO2", Ryan J. Gasvoda, Alex W. van der Steeg, Ranadeep Bhowmick, Eric A. Hudson, and Sumit Agarwal, Applied Materials and Interfaces, 9, pp. 31067-31075 (2017). As described therein, a fluorocarbon (CF) is deposited on the SiO2 layer. x ) film layer. CF x The F atoms in the film combine with Si in the SiO2 film to form volatile SiF4. x The C atoms in the film combine with oxygen (O) to form volatile carbon monoxide (CO) and carbon dioxide (CO2). At low bombardment energy (<25 eV), CF x The film deposition rate is greater than the ion-assisted removal rate, and a CF film with a thickness greater than a predetermined thickness is deposited on the surface. x When the film thickness is greater than the predetermined thickness, CF x The film inhibits etching of the underlying SiO2 layer by preventing volatile etch products from diffusing to the surface and preventing ions from reaching the CFx / SiO2 interface. In some examples, the predetermined thickness is in the range of 0.7-10 nm, depending on the plasma conditions.

[0053] The process can also be used for topography selective ALD. The technique can be used to perform ALD on planar surfaces relative to sidewalls, and vice versa, regardless of their chemical composition, as described below. Due to the directional control of the FC film thickness, the technique may be particularly suitable for SiO x The planar areas of SiN and / or Si prevent SiN and Si films from being deposited on the sidewalls.

[0054] For example, selective ALD growth on planar surfaces relative to sidewalls may be desirable in certain semiconductor manufacturing applications. Due to the anisotropy of the ion-mediated activation step (where ions preferentially strike planar surfaces to a greater extent than sidewalls), the FC deposition process can be tuned to more efficiently remove the FC stop layer from planar surfaces than from vertical surfaces, regardless of its composition. This effect can be used to achieve selective ALD growth on planar SiO2 relative to sidewalls. x The process can be adjusted so that the vertical surfaces of SiN and / or Si are blocked by the FC blocking layer to form an ALD film on the SiO x ALD growth is achieved on flat surfaces.

[0055] On the other hand, if the planar surface comprises SiN and / or Si, and sidewall ALD growth is desired, one or more oxygen-containing plasma flash steps can be periodically used to reduce the sidewall buildup of the FC barrier layer. Unless significant ion impact or ion bombardment is used in the activation step, the thickness of the FC film is generally thicker on the planar surface than on the sidewalls. The oxygen-containing flash step will first remove the thinner FC layer, thereby reducing the sidewall buildup. This effect can be used to deposit the FC barrier layer selectively on the SiN and / or Si planar surfaces relative to the sidewalls. As a result, as will be further described below, the technology has the flexibility to achieve various morphology-selective ALD configurations through process adjustments.

[0056] Depending on the chemistry of the ALD film, periodic re-deposition of the FC stop layer during the ALD process may be beneficial. In one example, the FC stop layer may be deposited after every x ALD cycles, where x is defined as between 1 and 100 cycles depending on the ALD precursor and reactant chemistry. The process may also include a step of removing ALD nuclei formed on the FC stop layer. The defect removal step may include a chemical etching process, a plasma enhanced etching process, or removal of the top surface of the FC layer. Mushrooming or "mushrooming" of the ALD film during deposition may be prevented by depositing the FC on the sidewalls of the growth layer, or by continuous growth of the FC stop layer along with the height of the ALD layer, where the ALD film grows laterally above the surface of the FC stop layer starting from the interface of the ALD / FC film.

[0057] Now refer to Figure 1 , showing a first example of a process for forming a FC barrier layer. In some examples, the process includes advanced mixed mode pulse modulation (AMMP TM During the first phase, alternating deposition (D) and activation (A) steps are performed to increase the relative molecular mass of SiO due to differences in chemical bonding and reactivity. x The FC film is deposited preferentially on Si or SiN surfaces. After a predetermined number of iterations, an oxygen flash step can be performed to remove some of the FC film. Where the FC film is thinnest, it can be completely removed while still retaining the FC film in areas where it is thicker. This process can be repeated one or more times to deposit FC films on SiN and Si surfaces but not on SiO x The thickness of the FC layer is increased on the surface.

[0058] Reference now FIG. 2A to FIG. 2D , shows the substrate 10 during selective ALD using the FC stop layer as described above. Figure 2A In the embodiment, the substrate 10 includes one or more underlying layers 12, a first film 14 mainly composed of SiN or silicon (Si), and a second film 14 mainly composed of SiO x The second film 16 is composed of a FC blocking layer 18 preferably deposited on SiN or Si. Figure 2B In FIG. 1 , the ALD layer 22 is selectively deposited on the second film 16 relative to the first film 14 due to the FC stop layer 18 .

[0059] In some examples, ALD layer 22 comprises a monolayer. In other examples, ALD layer 22 is less than a monolayer, such as 0.4 monolayers, or greater than a monolayer, such as greater than 1 monolayer to 4 monolayers. The FC layer significantly reduces ALD nucleation or prevents ALD film deposition due to chemical and / or physical inhibition. Figure 2C In the process, a further ALD layer 24 is deposited to form Figure 2D An ALD film 30 is shown.

[0060] Reference now Figure 3A and 3B , shows a substrate 10 during selective ALD using a FC stop layer and defect removal or repair. Figure 3A In the ALD process, nucleation defects 34 may be formed on top of or within the FC layer 18 during ALD. When the ALD film 30 is deposited using alternating FC deposition and activation steps, the defects 34 may be removed during the deposition of the FC stop layer 18. Figure 3B, the FC stop layer 18 is shown after removing nucleation defects. In some examples, process parameters such as the number of activation cycles, duration of activation cycles, and / or process parameters such as RF power or ESC bias or process pressure during activation cycles are adjusted to remove defects.

[0061] Reference now FIG. 4A to FIG. 4C , shows a substrate during selective ALD using a FC stop layer. Figure 4A In the embodiment of the present invention, mushroom-like portions 33 of the ALD film 30 may appear during processing. As used herein, mushroom-shaped growth refers to the growth of the ALD film in a horizontal or lateral direction (from the surface level outward of the sidewalls of the ALD film) in addition to the desired vertical direction. According to the present disclosure, there are two mechanisms for removing or compensating for mushroom-shaped growth of the ALD film 30. In Figure 4B , the FC deposition and activation steps are cycled to continue deposition of the FC stop layer as the thickness of the ALD film 30 increases. In other words, the process switches from an ALD cycle to a FC deposition / activation cycle and then back one or more times.

[0062] exist Figure 4C In the embodiment of the present invention, the FC deposition and activation can be adjusted to be highly directional. A small amount of FC film is deposited on the sidewalls of the ALD film 30 to slow down the lateral growth of the ALD film 30.

[0063] Reference now FIG. 5A to FIG. 5C , showing the main Si or SiN sidewall (relative to the main SiO x FC is selectively deposited on the sidewalls of the substrate 100 to substantially block ALD during subsequent deposition steps. Figure 5A In the invention, the substrate 100 comprises SiO x Layer 112, deposited on SiO x The SiN layer 114 on the layer 112 and the SiO deposited on the SiN layer 114 x Layer 118. Figure 5B In the embodiment, the FC stop layer 120 is deposited on the exposed sidewall surfaces of the SiN layer 114. Figure 5C In the embodiment of the present invention, deposition of the ALD layer 121 is substantially prevented in the region where the FC stop layer 120 is present.

[0064] Reference now FIG. 6A to FIG. 6E , shows the substrate 130 during the selective deposition of the FC stop layer. Fig. 6A In the embodiment, the substrate 130 includes a SiN layer 142, a SiO layer deposited on the SiN layer 142, x layer 144 and deposited on SiO x SiN layer 148 on layer 144. FC blocking layer relative to SiO xThe surface is preferentially deposited on the SiN surfaces at the flat and sidewalls. Then, due to the ion-mediated directionality of the activation step, the FC stop layer is removed faster from the flat surfaces than from the sidewalls. Therefore, the activation step (such as duration, frequency or process parameters) is changed to leave the FC stop layer on the SiN sidewalls 150 and on the SiN flat surfaces at 152, as shown in FIG. Figure 6B After ALD, Figure 6C As shown, SiO2 is deposited at 153 in the area where the FC barrier layer does not exist.

[0065] exist Fig.6D In the example of FIG. 1 , the activation step is changed to leave the FC stop layer only on the sidewalls 150 of the SiN. After ALD, SiO2 is deposited at 155 in the area where the FC stop layer does not exist, as shown in FIG. Fig. 6E shown.

[0066] Now refer to Figure 7 The number and duration of the deposition, activation and / or oxygen flash steps can be varied to achieve different effects. Figure 7 In the embodiment of the present invention, the deposition of the FC stop layer is performed using a shorter activation step and ends with a longer deposition step. In other words, the relative time periods and number of activation steps and deposition steps can be varied. Figure 7 There is only one activation step, and D>>A, for Figure 1 Not so. Figure 1 The duration D=A in the process. The FC stop layer is deposited on the flat areas of SiO2 or SiN at a greater rate than the rate of deposition on the sidewalls. Then, an oxygen flash step is used to remove the FC layer from the sidewalls. Subsequently, selective ALD is performed on the unstopped sidewalls. The activation step can be used to address the formation of nucleation defects or the adjustment of the FC stop layer. This process allows for larger FC accumulation on the flat areas, thereby enabling selective ALD to be performed on the sidewalls relative to the flat areas.

[0067] Reference now Fig. 8A , the substrate 160 includes SiO x Layer 172, deposited on SiO x The SiN layer 174 on the layer 172 and the SiO x Layer 178. Used in Figure 7 The method shown deposits FC blocking layers 180, 182 on SiO x On a flat surface. Figure 8B , the substrate 160 is shown after selective deposition of an ALD film 190 on the sidewalls and removal of the FC stop layers 180 , 182 on the flat surfaces.

[0068] Reference now Fig.9A and 9B, shows a substrate 200 during selective ALD using a FC stop layer. Fig.9A In the embodiment, the substrate 200 includes a SiN layer 212, a SiO layer deposited on the SiN layer 212, x layer 214 and deposited on SiO x SiN layer 218 on layer 214. Figure 7 The method shown deposits FC blocking layers 220, 222 on a flat SiN surface. Fig. 9B , the substrate 160 is shown after the ALD film 230 is selectively deposited on the sidewalls and the FC stop layers 220 , 222 on the flat surfaces are removed.

[0069] Reference now Fig.10 , showing the FC film thickness as a function of time. FC buildup is shown for a process with multiple deposition (D) and activation (A) cycles and few or no intermediate oxygen flash steps. Deposition and activation cycles can continue throughout the AMMP period. In some examples, if the duration of the activation period is long enough, it is possible to generate FC from SiN and SiO x The FC stop layer is removed from the surface (not shown). Due to the ion-mediated and directional nature of the activation step, more material is removed from the flat surfaces compared to the sidewall surfaces. This process allows more sidewall deposits to be used to perform selective ALD on the flat areas relative to the stopped sidewalls.

[0070] exist FIG. 11A to FIG. 11B In the embodiment, the substrate 260 includes SiO x Layer 272, deposited on SiO x The SiN layer 274 on the layer 272 and the SiO deposited on the SiN layer 274 x Layer 278. Use Fig.10 In the process shown, the FC blocking layer 280 is deposited on the SiN layer 274 and the SiO x On the sidewall surface of layer 272, as Fig.11A As shown. ALD films 292 and 290 are selectively deposited on SiO x Layer 272 and SiO x The flat surface of layer 278 and FC blocking layer 280 are removed, as shown in FIG. Fig. 11B shown.

[0071] exist Fig. 12A and 12B In the embodiment, the substrate 300 includes a SiN layer 312, a SiO layer deposited on the SiN layer 312, x layer 314 and deposited on SiO x SiN layer 318 on layer 314. Fig.10In the process shown, the FC blocking layer 320 is deposited on the SiO x On the sidewall surfaces of the SiN layer 314 and the SiN layer 312, as Fig. 12A As shown, the ALD films 330 and 332 are selectively deposited on the SiO x Layer 312 and SiO x The flat surface of layer 318 is formed, and the FC blocking layer 320 is removed, as shown in FIG. Fig. 12B shown.

[0072] exist Fig.13A In the embodiment, the substrate 400 includes a SiN layer 412, a SiO layer deposited on the SiN layer 412, x layer 414 and deposited on SiO x The SiN layer 418 is deposited on the SiN layer 412, the SiO x The FC layer 420 in the planar region of the substrate is removed by ion bombardment. Fig. 13B After the ion bombardment shown, the FC blocking layer 420 remains on the sidewalls of the substrate 400. Subsequently, ALD films 430 and 432 are selectively deposited on the planar surfaces of the SiN layers 412 and 418. The FC blocking layer 420 is removed, as shown in FIG. Fig. 13C shown.

[0073] Reference now Fig.14 , a method 600 for selectively depositing an ALD dielectric layer or a metal layer on a substrate is shown. At 610, a substrate is arranged on a substrate support in a processing chamber. At 614, processing chamber parameters, such as temperature, RF plasma power, ESC bias power, pressure and / or gas flow, are set. At 618, a FC blocking layer is deposited on a selected portion of the substrate. As described herein, the FC blocking layer can be deposited using a combination of deposition, activation and / or oxygen flash steps as described above. Alternatively, as described above, the FC blocking layer can be deposited using a deposition step and using an additional ion bombardment treatment. Ion bombardment also occurs during the activation step.

[0074] At 624, an ALD dielectric layer or metal layer is selectively deposited on the exposed portions of the substrate, but not on the areas of the substrate where the FC stop layer remains. At 630, the FC stop layer is removed.

[0075] Reference now Fig.15, a method 650 for selectively depositing an FC stop layer is shown. At 660, a plasma gas mixture is supplied to a process chamber. In some examples, the plasma gas mixture includes a combination of one or more of a fluorocarbon species, a hydrocarbon species, an inert gas species, and a hydrogen species. At 664, a plasma is ignited in the chamber. At 668, the plasma is sustained for a predetermined period of time, and the FC stop layer is deposited onto the substrate. At 670, the plasma is extinguished and the process chamber is purged.

[0076] At 671, an activation gas mixture is optionally supplied to the process chamber. At 672, a plasma is optionally energized for a predetermined period of time to perform an activation plasma treatment. At 674, after a predetermined activation period of time, the plasma is extinguished and the chamber is purged. At 676, the deposition and activation steps may be repeated one or more times by returning to 660.

[0077] At 677, an oxygen flash gas mixture is optionally supplied to the process chamber. At 678, a plasma is optionally energized for a predetermined period of time to perform an oxygen-containing flash treatment. At 680, the plasma is extinguished after the oxygen flash treatment period, and the chamber is purged. At 682, the process may be repeated one or more times by returning to 660. Thereafter, a mask repair may be optionally performed at 684. A mask repair step may be applied to the FC layer to remove nucleation sites for ALD. For example, a plasma treatment step may be performed. The plasma treatment step may include applying H2 plasma to the FC film. Then, ALD may be performed.

[0078] Reference now Fig.16 , another method 700 for depositing a FC stop layer is shown. At 660, a plasma gas mixture is supplied to a processing chamber. In some examples, the plasma gas mixture includes a fluorocarbon substance. At 664, a plasma is energized in the chamber. At 668, the plasma is sustained for a predetermined period of time, and the FC stop layer is deposited onto the substrate. At 670, the plasma is extinguished and the processing chamber is purged. At 719, an etching gas mixture is supplied to the chamber. At 720, the plasma is energized and ion bombardment is used to etch the flat areas of the FC stop layer faster than the FC stop layer on the sidewalls. Thereafter, ALD can be performed.

[0079] The foregoing description is merely illustrative in nature and is by no means intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because when studying the drawings, the specification and the appended claims, other modifications will become apparent. It should be understood that one or more steps in the method can be performed in different orders (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more of those features described relative to any embodiment of the present disclosure can be implemented in the features of any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and the replacement of one or more embodiments with each other remains within the scope of the present disclosure.

[0080] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "above," "below," and "disposed." Unless the relationship between a first and a second element is explicitly described as "direct," when such a relationship is described in the above disclosure, the relationship can be a direct relationship, in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship, in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B, and C" should be interpreted to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be interpreted to mean "at least one of A, at least one of B, and at least one of C."

Claims

1. A method for selectively depositing a film, comprising: a) arranging a substrate in a process chamber, wherein the substrate comprises a first material and a second material, the first material being exposed and comprising silicon oxide (SiO z ), the second material is exposed and is selected from silicon (Si) and silicon nitride (Si x N y ), where z, x and y are numbers defining the chemical ratios of the elements; b) supplying a first gas mixture comprising a fluorocarbon species and a hydrogen species; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the substrate; d) removing the first gas mixture from the process chamber; e) supplying a second gas mixture and energizing the plasma for a second predetermined period of time to perform the removing step; and f) removing the second gas mixture from the process chamber.

2. The method according to claim 1, wherein: The removing step preferentially removes the fluorocarbon layer on the first material over the fluorocarbon layer on the second material.

3. The method according to claim 2, further comprising: g) repeat b) to f) N times, where N is an integer; as well as h) depositing a film on said first material and substantially preventing film deposition on said second material using said fluorocarbon layer.

4. The method according to claim 1, wherein: The removing step preferentially removes the fluorocarbon layer on the sidewalls of the substrate compared to the fluorocarbon layer on the planar surface of the substrate.

5. The method according to claim 4, further comprising: g) repeat b) to f) N times, where N is an integer; as well as h) depositing a film on the sidewalls and substantially preventing the film from depositing on the planar surface using the fluorocarbon layer.

6. The method according to claim 1, wherein: The removing step preferentially removes the fluorocarbon layer on the planar surface of the substrate compared to the fluorocarbon layer on the sidewalls of the substrate.

7. The method according to claim 6, further comprising: g) repeat b) to f) N times, where N is an integer; as well as h) depositing a film on said planar surface and substantially preventing said film from depositing on said sidewalls using said fluorocarbon layer.

8. The method according to claim 1, further comprising: g) repeat b) to f) N times, where N is an integer; as well as h) selectively depositing a film on exposed portions of the first material and the second material of the substrate and substantially preventing the film from being deposited on the substrate using a fluorocarbon layer.

9. The method according to claim 1, wherein: The first gas mixture comprises a gas selected from fluorocarbon gases (C a F b ), hydrocarbon gas (H c C d ), hydrofluorocarbon gases (C e F f H g ), molecular hydrogen gas (H2), and combinations thereof, wherein a, b, c, d, e, f, and g are numbers defining the chemical ratios of the elements.

10. The method according to claim 1, wherein: The first gas mixture further comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

11. The method according to claim 1, wherein: The second gas mixture includes one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

12. The method of claim 8, wherein h) comprises performing atomic layer deposition (ALD).

13. The method of claim 8, further comprising, after g) and before h): g1) supplying a third gas mixture including an oxygen species; and g2) Exciting a plasma for a predetermined period of time.

14. The method according to claim 13, further comprising: g3) Repeat a) to g2) one or more times.

15. The method according to claim 13, wherein: The third gas mixture contains one or more gases selected from the group consisting of molecular oxygen (O2), ozone (O3), water (H2O), carbon dioxide (CO2), carbon monoxide (CO) and nitrous oxide (N2O).

16. The method according to claim 13, wherein: The predetermined time period is in the range from 0.5 seconds to 30 seconds.

17. The method of claim 12, wherein: The substrate includes a first silicon dioxide layer, a silicon nitride layer disposed above the first silicon dioxide layer, and a second silicon dioxide layer disposed above the silicon nitride layer, The fluorocarbon layer is selectively deposited on the sidewalls of the silicon nitride layer and the second silicon dioxide layer, The film is selectively deposited on planar regions of the first and second silicon dioxide layers and is substantially stopped by the fluorocarbon layer on the sidewalls of the silicon nitride and second silicon dioxide layers.

18. The method of claim 8, wherein: The substrate includes a first silicon nitride layer, a silicon dioxide layer disposed above the first silicon nitride layer, and a second silicon nitride layer disposed above the silicon dioxide layer; The fluorocarbon layer is selectively deposited on the sidewalls of the silicon dioxide layer and the second silicon nitride layer, and The film is deposited on planar regions of the first and second silicon nitride layers and is substantially stopped by the fluorocarbon layer on the sidewalls of the silicon dioxide layer and the second silicon nitride layer.

19. The method of claim 8, wherein: The substrate includes a first silicon dioxide layer, a silicon nitride layer disposed above the first silicon dioxide layer, and a second silicon dioxide layer disposed above the silicon nitride layer, The fluorocarbon layer is selectively deposited on the planar surfaces of the first silicon dioxide layer and the second silicon dioxide layer, and The film is deposited on sidewalls of the silicon nitride layer and the second silicon dioxide layer and is substantially stopped by the fluorocarbon layer on the planar surfaces of the first silicon dioxide layer and the second silicon dioxide layer.

20. The method of claim 8, wherein: The substrate includes a first silicon nitride layer, a silicon dioxide layer disposed above the first silicon nitride layer, and a second silicon nitride layer disposed above the silicon dioxide layer; The fluorocarbon layer is selectively deposited on the planar surfaces of the first silicon nitride layer and the second silicon nitride layer, and The film is deposited on sidewalls of the silicon dioxide layer and the second silicon nitride layer and is substantially stopped by the fluorocarbon layer on planar surfaces of the first silicon nitride layer and the second silicon nitride layer.

21. The method according to claim 12, wherein: The film includes an ALD dielectric layer.

22. The method according to claim 12, wherein: The film includes an ALD metal layer.

23. A method for selectively depositing a film, comprising: a) placing a substrate in a processing chamber, wherein the substrate comprises silicon oxide (SiO z ) and a first exposed material selected from silicon (Si) and silicon nitride (Si x N y ), wherein z, x, and y are numbers defining chemical ratios of the elements; b) supplying a gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the substrate; d) removing the gas mixture from the process chamber; e) performing ion bombardment to remove portions of the fluorocarbon layer from planar portions of the substrate; and f) selectively depositing a film on said planar surface portion of said substrate and substantially preventing said film from being deposited on sidewalls of said substrate using said fluorocarbon layer.

24. The method according to claim 23, wherein: The gas mixture comprises a gas selected from fluorocarbon gases (C a F b ), hydrocarbon gas (H c C d ), hydrofluorocarbon gases (C e F f H g ), molecular hydrogen gas (H2), and combinations thereof, wherein a, b, c, d, e, f, and g are numbers defining the chemical ratios of the elements.

25. The method according to claim 23, wherein: The gas mixture further comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

26. The method of claim 23, wherein: f) includes performing atomic layer deposition (ALD).

27. The method according to claim 26, wherein: The film includes an ALD dielectric layer.

28. The method according to claim 26, wherein: The film includes an ALD metal layer.

29. A method for selectively depositing a film, comprising: a) placing a substrate in a processing chamber, wherein the substrate comprises silicon oxide (SiO z ) and a first exposed material selected from silicon (Si) and silicon nitride (Si x N y ), wherein z, x, and y are numbers defining chemical ratios of the elements; b) supplying a gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the second exposed material of the substrate; d) removing the gas mixture from the process chamber; e) depositing a film on the first exposed material using atomic layer deposition; f) removing reactants from the process chamber; g) repeating depositing the fluorocarbon layer in b) to e) and depositing the film in e) and f) one or more times to deposit the film on the first exposed material without mushrooming the film.

30. The method of claim 29, wherein: The gas mixture comprises a gas selected from fluorocarbon gases (C a F b ), hydrocarbon gas (H c C d ), hydrofluorocarbon gases (C e F f H g ), molecular hydrogen gas (H2), and combinations thereof, wherein a, b, c, d, e, f, and g are numbers defining the chemical ratios of the elements.

31. The method of claim 29, wherein: The gas mixture further comprises one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

32. A method for selectively depositing a film, comprising: a) placing a substrate in a processing chamber, wherein the substrate comprises silicon oxide (SiO z ) and a first exposed material selected from silicon (Si) and silicon nitride (Si x N y ), wherein z, x, and y are numbers defining chemical ratios of the elements; b) supplying a gas mixture comprising a fluorocarbon substance and a hydrogen substance; c) energizing a plasma for a first predetermined period of time to deposit a fluorocarbon layer on the second exposed material of the substrate; d) removing the gas mixture from the process chamber; e) depositing a film on the first exposed material using atomic layer deposition; f) removing reactants from the process chamber; g) supplying a second gas mixture and energizing the plasma for a second predetermined period of time to perform the removing step; and h) removing the second gas mixture from the process chamber.

33. The method of claim 32, wherein: The removing step preferentially removes the fluorocarbon layer on the first exposed material over the fluorocarbon layer on the second exposed material.

34. The method of claim 32, further comprising repeating at least one of the following: Depositing the fluorocarbon layer in b) to d); depositing the films in e) and f); and The removal steps in g) and h).

35. The method of claim 32, wherein: The removal steps in g) and h) are used to remove nucleation defects in the fluorocarbon layer.

36. The method of claim 32, wherein: The second gas mixture includes one or more gases selected from the group consisting of helium (He), nitrogen (N2), xenon (Xe), krypton (Kr) and argon (Ar).

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