Substrate processing method
The PEALD method circulates the supply of silicon precursors and oxidizers in the concave structure of the semiconductor device to form a silicon oxide film, which solves the problems of poor film uniformity and unstable dielectric constant in the concave structure, and realizes the effective formation of low-k-value films and Highly efficient deposition.
Patent Information
- Application Number
- CN202411026210.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-08-02
- Filing Date
- 2024-07-30
- Publication Date
- 2025-02-18
AI Technical Summary
As the critical size of the semiconductor device decreases, the uniformity of the film deposited in the concave structure becomes worse, resulting in an adverse effect on the dielectric constant of the film, and it is difficult to effectively form a film with a lower k value.
Through the plasma enhanced atomic layer deposition (PEALD) method, a variety of silicon precursors and oxidants are supplied, and the silicon oxide film is repeatedly formed in a cycle to ensure that the film is conformally covered along the gap structure and a low-k value film is formed in a narrow gap.
The film with good step coverage characteristics and low k value is formed in the concave structure, which improves the control of the uniformity and dielectric constant of the film, and meets the demand for low k films in semiconductor devices.
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Figure CN119480791A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to a method of forming a low-k film on a substrate, and more particularly, to a method of forming a low-k film in a recess by a plasma enhanced atomic layer deposition (PEALD) method. Background Art
[0002] As the critical dimension (CD) of semiconductor devices shrinks, electrical interference between material layers constituting the device circuit increases. Electrical interference (e.g., resistance) in the circuit leads to RC (resistance-capacitance) delay caused by the insulating layer and becomes one of the main reasons for the slow response time of semiconductor devices. In order to reduce the RC delay in the circuit, films with low k values (i.e., films with low dielectric constants), such as SiO, SiOC, and SiOCH, have been introduced.
[0003] Low-k films are used for lining applications in TSV (Through Silicon Via) processes, in which low-k films are formed thinly and conformally along the surface of recessed areas (e.g., forming vias between metal layers). Low-k films with k values less than 3.9 are obtained by conventional plasma enhanced chemical vapor deposition (PECVD) methods. For example, SiO 2 Or SiN or a combination thereof can be used as a liner layer for low-k films. However, as the critical dimensions of semiconductor devices continue to shrink, the uniformity of the film deposited in the recessed structure deteriorates. For example, during the PECVD process, a protrusion may appear at the upper portion of the recess, resulting in a non-conformal film that adversely affects the k value (i.e., dielectric constant) of the film. In addition, as devices continue to shrink, films with lower k values (e.g., 3.5 or lower) are required.
[0004] Figure 1 Film deposition along the recessed surface by conventional PECVD methods is shown. Figure 1 can be part of a TSV process where SiO 2 A low-k film of Si or SiN can be formed as a lining on the walls of the recess, followed by forming a barrier film such as Ta / TaN thereon, filling the recess with copper, and planarizing the substrate from the top and bottom of the substrate. Figure 1 The PECVD process shows a high film growth rate, but it results in non-conformal film deposition along the surface (eg, protrusions in the upper region of the gap).
[0005] Therefore, it is necessary to conformally form a film having a low-k value of 3.5 or less along the surface of the recess structure. Summary of the invention
[0006] The present invention discloses a method for forming a film having good step coverage characteristics along a gap structure and having a low-k value in a narrow gap structure. Specifically, the present disclosure discloses a PEALD method for forming a low-k film by supplying multiple precursors.
[0007] In one or more embodiments, the method for forming a low-k film includes the following steps: supplying a first silicon precursor to a reactor, supplying a second silicon precursor, and supplying an oxidant to the reactor, and these steps are cyclically repeated multiple times to form a silicon oxide film.
[0008] In one or more embodiments, the first silicon precursor may include a reactive group including an alkylamine and a non-reactive group including an alkyl group and a hydrogen group, and the second silicon precursor may include a reactive group including an alkylamine and a non-reactive group including a hydrogen group.
[0009] In one or more embodiments, the first silicon precursor may be an organic silane amine, and the second silicon precursor may be an aminosilane.
[0010] In one or more embodiments, the first silicon precursor may include at least one of: (dimethylamino)trimethylsilane, bis(dimethylamino)dimethylsilane, N,N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, N,N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, or a combination thereof.
[0011] In one or more embodiments, the second precursor may include at least one of the following: DSMA, (SiH 3 ) 2 NMe; DSEA, (SiH 3 ) 2 NEt;DSIPA,(SiH 3 ) 2 N(iPr);DSTBA,(SiH 3 ) 2 N(tBu);DEAS,SiH 3 Nt 2 ;DTBAS,SiH 3 N(tBu) 2 ; BDEAS,SiH 2 (NEt 2 ) 2 ; BDMAS,SiH 2 (NMe 2 ) 2 ;BTBAS,SiH 2 (NHtBu) 2 ; DIPAS,SiH 3 N(iPr) 2 ;3DMAS,SiH(N(Me) 2 ) 3 ; BEMAS,SiH 2 [N(Et)(Me)]2 ;TEMS,SiH(NEtMe) 3 ;TIPAS,SiH(NHiPr) 3 ;BDIPADS,(N(iPr) 2 )SiH 2 -SiH 2 (N(iPr) 2 );BDEADS,(NEt 2 )SiH 2 -SiH 2 (NEt 2 ); BDPADS, (NPr 2 )SiH 2 -SiH 2 (NPr 2 ) or a combination thereof.
[0012] In one or more embodiments, the oxidant may include oxygen plasma, CO 2 Plasma, N 2 O plasma, ozone, or a combination thereof.
[0013] In one or more embodiments, the method further includes supplying a hydrogen-containing gas in all steps.
[0014] In one or more embodiments, the method further includes performing a post-treatment to remove moisture from the silicon oxide film.
[0015] In one or more embodiments, the post-treatment may be performed by at least one of a thermal treatment and a plasma treatment, a UV treatment, a VUV treatment, or a combination thereof.
[0016] In one or more embodiments, the plasma post-treatment may be performed by providing at least one of argon plasma, helium plasma, hydrogen plasma, or a combination thereof.
[0017] In one or more embodiments, the dielectric constant of the silicon oxide film formed by this method may be 3.5 or less.
[0018] In one or more embodiments, the film growth rate of the silicon oxide film may be 0.1 nm / cycle or more.
[0019] This summary is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the detailed description of the example embodiments disclosed below. This summary is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1Film deposition along the recessed surface by conventional PECVD methods is shown.
[0021] Figure 2 The process flow of forming a low-k film using this method is shown.
[0022] Figure 3 Shows Figure 2 Timing diagram of the process.
[0023] Figure 4 Another process flow for forming a low-k film using this method is shown.
[0024] Figure 5 Shows Figure 4 Timing diagram of the process.
[0025] Figure 6 The film formation mechanism according to this method is explained.
[0026] Figure 7 The membrane structure before and after post-treatment is shown.
[0027] Figure 8 Shown are FT-IR absorbance graphs illustrating the film composition before post-treatment according to process conditions.
[0028] Fig. 9 FIG. 5 shows a TEM image of a low-k film formed on the sidewall of a TSV device using this method.
[0029] Fig.10 A TSV process to which embodiments of the present disclosure may be applied is shown.
[0030] It should be understood that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the size of some elements in the drawings may be exaggerated relative to other elements to help improve the understanding of the illustrated embodiments of the present disclosure. DETAILED DESCRIPTION
[0031] Although certain embodiments and examples are disclosed below, those skilled in the art will appreciate that the invention extends beyond the specifically disclosed embodiments and / or uses of the invention and their obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited by the specifically disclosed embodiments described below.
[0032] As used herein, the term "substrate" may refer to any one or more underlying materials, including any one or more underlying materials that may be modified or on which a device, circuit, or film may be formed. A "substrate" may be continuous or non-continuous; rigid or flexible; solid or porous; and combinations thereof. A substrate may be in any form, such as a powder, a plate, or a workpiece. A plate-like substrate may include wafers of various shapes and sizes. A substrate may be made of semiconductor materials, including, for example, silicon, silicon germanium, silicon oxide, gallium arsenide, gallium nitride, and silicon carbide.
[0033] The continuous substrate may extend beyond the boundaries of the processing chamber in which the deposition process occurs. In some processes, the continuous substrate may be moved through the processing chamber so that the process continues until the end of the substrate is reached. The continuous substrate may be provided from a continuous substrate feed system to allow the continuous substrate to be manufactured and output in any suitable form.
[0034] The illustrations presented herein are not meant to be actual views of any particular material, structure, or device but are merely idealized representations used to describe embodiments of the present disclosure.
[0035] The specific embodiments shown and described are illustrations of the present invention and its best mode and are not intended to limit the scope of these aspects and embodiments in any way. In fact, for the sake of brevity, the traditional manufacturing, connection, preparation and other functional aspects of the system may not be described in detail. In addition, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or physical connections between various elements. Many alternative or additional functional relationships or physical connections may exist in actual systems, and / or may not exist in some embodiments.
[0036] Figure 2 A process flow for forming a low-k film using this method is shown. Each step of the process flow will be described in more detail below.
[0037] exist Figure 2 In step 100, a substrate is provided to a reactor. The substrate may include recessed structures, such as gaps, 3D device structures, and through holes penetrating the substrate. The substrate may be loaded onto a substrate support, such as a pedestal. The pedestal may be part of a heating block that provides thermal energy to the pedestal.
[0038] In step 110, a first silicon precursor is supplied to the reactor. The first silicon precursor may be adsorbed onto the reaction sites formed on the surface of the substrate. For example, the first silicon precursor may be conformally adsorbed onto the surface along the gap structure.
[0039] The first silicon precursor may include a reactive group including an alkylamine and a non-reactive group including an alkyl group and a hydrogen group surrounding the silicon element. For example, the first silicon precursor may include an organic silane amine group. More specifically, the first silicon precursor may be at least one of: (dimethylamino) trimethylsilane, bis (dimethylamino) dimethylsilane, N, N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, N, N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine or a combination thereof.
[0040] In step 120, a second silicon precursor is supplied to the reactor. The second silicon precursor may be adsorbed onto the remaining reaction sites formed on the substrate surface but not occupied by the first silicon precursor. For example, the second silicon precursor may be conformally adsorbed onto the surface along the gap structure.
[0041] The second silicon precursor may include a reactive group including an alkylamine and a non-reactive group including a hydrogen group surrounding a silicon element. For example, the second silicon precursor may include aminosilane. More specifically, the second silicon precursor may be at least one of the following: DSMA, (SiH 3 ) 2 NMe; DSEA, (SiH 3 ) 2 NEt;DSIPA,(SiH 3 ) 2 N(iPr);DSTBA,(SiH 3 ) 2 N(tBu);DEAS,SiH 3 Nt 2 ;DTBAS,SiH 3 N(tBu) 2 ; BDEAS,SiH 2 (NEt 2 ) 2 ; BDMAS,SiH 2 (NMe 2 ) 2 ;BTBAS,SiH 2 (NHtBu) 2 ; DIPAS,SiH 3 N(iPr) 2 ;3DMAS,SiH(N(Me) 2 ) 3 ; BEMAS,SiH 2 [N(Et)(Me)] 2 ;TEMS,SiH(NEtMe) 3 ;TIPAS,SiH(NHiPr) 3 ;BDIPADS,(N(iPr)2 )SiH 2 -SiH 2 (N(iPr) 2 );BDEADS,(NEt 2 )SiH 2 -SiH 2 (NEt 2 ); BDPADS, (NPr 2 )SiH 2 -SiH 2 (NPr 2 ) or a combination thereof.
[0042] After step 120, the film may include a silicon precursor layer including a first silicon precursor and a second silicon precursor. In steps 110 and 120, the non-reactive groups of the first silicon precursor and the non-reactive groups of the second silicon precursor may not participate in the chemical reaction between the first silicon precursor and the second silicon precursor for forming the silicon precursor layer, resulting in the formation of voids in the silicon precursor layer. The voids generated may reduce the k value of the silicon oxide film. The details of the reaction mechanism will be described later.
[0043] In step 130, an oxidant is supplied to the reactor. The oxidant may chemically react with the silicon precursor molecular layer formed in step 120 to form a silicon oxide film. The oxidant may be an oxygen-containing gas activated by RF power applied to the reactor in situ or remotely. The oxidant may include oxygen plasma, CO 2 Plasma, N 2 O plasma, ozone, or a combination thereof.
[0044] Steps 100 to 130 of forming a silicon oxide film may be performed at about 20° C. and about 100° C. or about 35° C. and about 90° C., and RF power between about 30 W and about 200 W or between about 40 W and about 150 W may be applied to dissociate and activate the oxygen-containing gas.
[0045] In step 140, it is measured whether the target thickness of the silicon oxide film is reached. If the target thickness is not reached, steps 110 to 130 may be repeated. If the target thickness is reached, the next step 140 is performed. The target thickness may be defined as a set thickness of the film to be formed on the recess wall.
[0046] Steps 110 to 130 may be repeated multiple times in a cycle. Multiple cycles may be input into a control system (e.g., software) of a substrate processing device. Whether the target thickness is reached is determined by measuring whether the required number of cycles has been performed. The film growth rate of the silicon oxide film formed in steps 110 to 140 may be 0.1 nm / cycle or greater.
[0047] Optionally, in step 150, post-treatment may be performed. The post-treatment may remove reaction byproducts, such as moisture, from the silicon oxide film. The post-treatment may be performed by heat treatment and / or at least one of plasma treatment, UV treatment, VUV treatment (vacuum UV treatment), or a combination thereof in situ or ex situ. In one embodiment, plasma post-treatment may be performed by supplying at least one of argon plasma, helium plasma, hydrogen plasma, or a combination thereof, wherein 500 W or less of RF power is applied between about 300° C. and about 500° C. or between about 350° C. and about 450° C. In another embodiment, in the plasma post-treatment, high frequency plasma power may be applied to improve the treatment effect (i.e., to remove more moisture). For example, a power of 10 MHz or higher may be applied.
[0048] In step 160, the process may end and the substrate may be unloaded from the reactor. In other embodiments, steps 110 to 140 and step 150 may be performed ex situ. In other words, steps 110 to 140 for forming the silicon oxide film may be performed in one reactor, and step 150 for post-processing may be performed in another reactor.
[0049] Figure 3 Shows Figure 2 Each step is described in more detail below.
[0050] Step T1 corresponds to Figure 2 Step 110, wherein a first silicon precursor may be supplied to the reactor.
[0051] Step T2 corresponds to Figure 2 In step 120, a second silicon precursor may be supplied to the reactor. The second silicon precursor may chemically react with the first silicon precursor and form a silicon precursor layer.
[0052] Step T4 corresponds to Figure 2 The step of supplying an oxidant 130 is as follows. The oxidant may chemically react with the silicon precursor layer and may form a silicon oxide film.
[0053] Step T6 corresponds to Figure 2 Step 150, wherein the silicon oxide film may be post-treated. The post-treatment may be performed optionally. The post-treatment is to remove moisture from the silicon oxide film. In one embodiment, plasma treatment may be performed as the post-treatment.
[0054] After step T4 and before step T5, and after step T5, a purge step may be further performed. In another embodiment, the purge step may be performed after step T1 and before step T2.
[0055] Steps T1 to T5 may be repeated multiple times until the silicon oxide film reaches a target thickness (ie, full gap filling), and step T6 may be repeated multiple times.
[0056] Figure 4 Another process flow for forming a low-k film using this method is shown.
[0057] exist Figure 4 In the example, except for step 270, steps 200 to 260 are the same as Figure 2 Therefore, a detailed description of steps 200 to 260 will not be given here. Figure 4 In the present invention, a new step 270 is provided. In step 270, a hydrogen-containing gas is supplied to the reactor throughout steps 200 to 260. Hydrogen helps to form -OH groups as bonding sites along the surface of the silicon precursor layer. Therefore, the step coverage of features and the film growth rate can be improved. The hydrogen-containing gas can be at least one of hydrogen, acyclic hydrocarbons or a combination thereof.
[0058] Figure 5 Shows Figure 4 Timing diagram of the process.
[0059] Figure 5 Similar to Figure 3 , in addition to further supplying hydrogen throughout the process. Hydrogen helps to form bonding sites such as -OH sites along the surface of the silicon precursor layer, thereby improving the step coverage in the gap structure.
[0060] Figure 6 The film formation mechanism according to this method is explained.
[0061] exist Figure 6 In step 1, a first silicon precursor may be supplied to the substrate. The first silicon precursor may include an organic silane amine group, which may include a reactive group R1 and non-reactive groups R2 and R3. More specifically, the first silicon precursor may be at least one of the following: (dimethylamino) trimethylsilane, bis (dimethylamino) dimethylsilane, N, N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, N, N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, or a combination thereof.
[0062] The reactive group R1 may include an alkylamine, the non-reactive group R2 may include an alkyl group (eg, -CH3), and the non-reactive group R3 may include a hydrogen group surrounding a silicon element (eg, -H).
[0063] In step 1, Si-OH and Si-CH 3The sites have already been formed on the substrate by the previous cycle. The reactive group R1 of the first silicon precursor can react with -OH and can form a Si-O-Si bonding structure thereon, but not with -CH 3 reaction, so no Si-O-Si bonding structure can be formed thereon.
[0064] In step 2, a second silicon precursor may be supplied to the substrate. The second silicon precursor may include aminosilane, which may include a reactive group R1 and a non-reactive group R3.
[0065] The reactive group R1 may include an alkylamine, and the non-reactive group R3 may include a hydrogen group (eg, -H) surrounding a silicon element.
[0066] The reactive group R1 can react with the remaining -OH sites formed on the substrate and can form a Si-O-Si bonding structure thereon. However, there may be no reaction with the non-reactive group R2 (i.e., -CH 3 ), and therefore, a Si-O-Si bonding structure may not be formed thereon. The space where the Si-O-Si bonding structure is not formed may become a space resulting in a void, as shown in step 3 later.
[0067] In step 3, the silicon precursor layer may be oxidized. The oxidation may be performed by supplying an oxidant to the reactor. The oxidant may be oxygen plasma, CO 2 Plasma, N 2 At least one of O plasma, ozone, or a combination thereof. The plasma may be generated by applying an RF power between about 30 W and about 200 W or between about 40 W and about 150 W to the reactor. By providing an oxidant, the oxygen element may react with the non-reactive group R3 (i.e., -H) and form an -OH group. The -OH group may react with other -OH groups in the film to form a Si-O-Si network structure and leave H in the film. 2 O is a byproduct, as shown in Formula A below.
[0068] [-Si-H,H-Si-]+oxidant→-Si-O-Si-+H 2 O(A)
[0069] On the other hand, the -OH groups that may have no other -OH groups to react with may remain as -OH sites on the surface of the film as shown in Formula B below, and serve as bonding sites (ie, reaction sites) for the first silicon precursor in the next cycle.
[0070] [-Si-H] + oxidant → -Si-OH (B)
[0071] Steps 1 to 3 may be performed at a temperature of 100° C. or lower, and repeated multiple times until a desired film thickness is obtained.
[0072] As described above, after the silicon oxide film is formed, in the presence of the non-reactive group R1 (-CH 3 ) space, so no Si-O-Si bonding structure is formed. According to the above formula A, in addition to the voids, water (i.e., H 2 O). Therefore, another step can be taken to remove the water therein.
[0073] In step 4, post-treatment may be performed to remove moisture from the silicon oxide film. The post-treatment may be performed at a high temperature, such as between about 300° C. and about 500° C. or between about 350° C. and about 450° C., to evaporate the moisture. In another embodiment, a plasma may be further provided to more effectively remove moisture. The plasma may be at least one of an argon plasma, a helium plasma, a hydrogen plasma, or a combination thereof. The plasma may bombard and destroy the silicon oxide film structure, thereby helping to more effectively drain moisture from the film. The plasma may be generated by applying an RF power between about 200 W and about 600 W or between about 300 W and about 500 W to the reactor and activating a gas such as argon, helium, hydrogen, and a combination thereof.
[0074] Figure 7 The membrane structure before and after post-treatment is shown. Figure 7 As shown, after post-treatment, moisture is removed from the membrane and more voids are formed.
[0075] Figure 8 FT-IR absorbance graphs showing film formation according to various silicon precursor supply sequences before post-treatment are shown.
[0076] exist Figure 8 In the embodiment, four silicon precursor supply sequences are performed: supplying only the first silicon precursor A, supplying only the second silicon precursor B, supplying the first silicon precursor followed by supplying the second silicon precursor C, and supplying the second silicon precursor followed by supplying the first silicon precursor D.
[0077] like Figure 8 As shown, no Si-CH 3 Peak (non-reactive group R2). In other words, no non-reactive group R2 was detected in the potential space for void formation, which means that the space was filled and no void was formed.
[0078] On the other hand, referring to sequence A and sequence C, Si-CH 3peak (non-reactive group R2). In other words, a space in which a void can be formed can be formed, and thus a void can be generated accordingly. More specifically, sequence C (i.e., supplying the first silicon precursor and then supplying the second silicon precursor) shows the highest Si-CH 3 That is, sequence C can generate more voids than sequence A. Therefore, by adopting sequence C as described in the present disclosure (i.e., supplying the first silicon precursor and then supplying the second precursor), a lower k value can be achieved, which is a technical benefit.
[0079] Table 1 shows the SiO formed according to the present disclosure. 2 Film properties of the film. In Table 1, the silicon oxide film is conformally formed along the surface of the gap structure with a width of 5.2um and a depth of 52um. The dielectric constant (k value) is about 3.5, achieving a target k value of 3.5 or less. As described above, post-processing removes moisture from the film, thereby enabling the formation of more voids. Therefore, performing post-processing has the technical benefit of reducing the k value. Test results show that the step coverage reaches 94%, achieving the expected goal.
[0080] Table 1 - SiO formed according to the present disclosure 2 Membrane properties
[0081]
[0082] Table 1 also shows the film growth rate of 0.1 nm or more. Therefore, supplying dual precursors has the technical benefit of increasing film growth rate and yield.
[0083] Fig. 9 TEM image of a low-k film formed on the sidewall of a gap using this method is shown.
[0084] Reference Fig. 9 , a silicon oxide film was conformally formed on the sidewalls of the gap by PEALD, followed by a post-processing step. The step coverage between the top and bottom sides was about 94%, and a k value of 3.42 was obtained, meeting the target range.
[0085] Table 2 shows the dielectric constants (k values) of silicon oxide films at different processing stages.
[0086] Table 2 - Dielectric constants (k values) of silicon oxide films
[0087]
[0088] As shown in Table 2, condition A (as deposited, with / without post-treatment) results in high k values (>5.0). Since the films are formed at low temperature and low RF power, the high k value of condition A may be due to the film network structure ( Figure 6 and Figure 7). Condition B (heat treatment only) also resulted in high k values (>5.0). The high k value of condition B may be caused by the moisture still remaining in the silicon oxide network structure ( Figure 6 and Figure 7 ).
[0089] The k value (~3.5) produced by condition C (heat treatment and plasma treatment) meets the target k value (3.5 or less). That is, simultaneous heat treatment and plasma treatment can further promote the removal of moisture from the membrane network structure and reduce the k value to the target value. In another embodiment, UV or VUV (vacuum UV) treatment can be performed instead of plasma treatment.
[0090] Table 3 shows process conditions for forming a low-k silicon oxide film according to the present disclosure.
[0091] Table 3 - Process Conditions for Forming Low-k Silicon Oxide Films
[0092]
[0093]
[0094] Substrate processing according to the present disclosure can be performed in situ or ex situ. For an in situ process, deposition and post-processing can be performed in one reactor. For an ex situ process, deposition can be performed in one reactor. After deposition is complete, the substrate can be transferred to another reactor and post-processed therein.
[0095] Fig.10 FIG. 2 shows a TSV process to which the embodiments of the present disclosure can be applied. Fig.10 As shown, the substrate processing method according to the embodiment of the present disclosure may then form a barrier film such as Ta / TaN on the silicon oxide film, fill the recessed structure with a conductive film, and planarize the substrate.
[0096] exist Fig.10 In A, a substrate 1 is provided having a recess 2. The recess may be a gap or a through hole.
[0097] exist Fig.10 In B, the liner 3 may be formed along the surface of the recess 2. The liner 3 may be a low-k film formed by the method of the present disclosure.
[0098] exist Fig.10 In FIG. 3 , a barrier film 4 may be formed on the liner 3. The barrier film may prevent the conductive element of the conductive film 5 formed in the next step from diffusing to the substrate 1 through the liner 3. The barrier film 4 may include at least one of Ta, TaN, Ta / TaN and TiN or a mixture thereof. The barrier film may be formed by at least one of ALD, PEALD, CVD or PECVD.
[0099] exist Fig.10 In D, the conductive film 5 may fill the concave portion 2. The conductive film 5 may include at least one of copper, tungsten, and polysilicon or a mixture thereof. The conductive film 5 may be formed by at least one of electrochemical deposition or CVD.
[0100] exist Fig.10 In E, planarization can be performed. In planarization, the substrate 1 can be planarized from the top t1, and ground from the opposite side of the substrate (i.e., the bottom of the substrate) t2. Although Fig.10 Not shown, but in a subsequent process, it can be stacked through Fig.10 A to 10E planarize the plurality of substrates, and thus form long and deep recesses and conductive films filled therein.
[0101] It should be understood that the configuration and / or method described herein are exemplary in nature, and these specific embodiments or examples should not be considered restrictive, because many variations are possible. The specific routine or method described herein can represent one or more of any number of processing strategies. Therefore, the various actions shown can be performed in the order shown, in other orders, or omitted in some cases.
[0102] The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various processes, systems and configurations, and other features, functions, acts and / or properties disclosed herein, and any and all equivalents thereof.
Claims
1. A method for forming a film on a wall of a recessed portion of a substrate in a reactor, comprising the following steps: supplying a first silicon precursor to the reactor; supplying a second silicon precursor to the reactor; as well as supplying an oxidant to the reactor; The first silicon precursor includes: (1) a reactive group including an alkylamine; and (2) a non-reactive group including an alkyl group and a hydrogen group; The second silicon precursor comprises: (1) a reactive group comprising an alkylamine; and (2) a non-reactive group comprising a hydrogen group; Here, these steps are repeated multiple times, and a silicon oxide film is formed on the wall of the concave portion.
2. The method according to claim 1, further comprising supplying a hydrogen-containing gas in all steps.
3. The method according to claim 2, wherein: The hydrogen-containing gas includes at least one of the following: hydrogen, acyclic hydrocarbons, or a combination thereof. 4 . The method according to claim 1 , further comprising performing a post-treatment to remove moisture from the silicon oxide film.
5. The method according to claim 4, wherein: The post-treatment is performed by heat treatment and at least one of plasma treatment, UV treatment, VUV treatment or a combination thereof.
6. The method according to claim 4, wherein: The post-treatment includes heat treatment and plasma treatment by supplying at least one of argon plasma, helium plasma, hydrogen plasma, or a combination thereof.
7. The method according to claim 6, wherein: The plasma is generated by applying about 200 W to about 600 W of RF power to the reactor either in situ or remotely.
8. The method according to claim 7, wherein: The plasma is generated by applying about 300 W to about 500 W of RF power to the reactor either in situ or remotely.
9. The method according to claim 5, wherein: The heat treatment is performed between about 300°C and about 500°C.
10. The method according to claim 9, wherein: The heat treatment is performed between about 350°C and about 450°C.
11. The method according to claim 4, wherein: The steps for forming the membrane and post-treatment are carried out in situ.
12. The method according to claim 4, wherein: The steps for forming the membrane and post-treatment are performed ex situ.
13. The method according to claim 4, wherein: The silicon oxide film has a dielectric constant of 3.5 or less.
14. The method according to claim 4, wherein: The film growth rate of the silicon oxide film is 0.1 nm / cycle or more.
15. The method according to claim 1, wherein: The first silicon precursor includes an organic silane amine group.
16. The method according to claim 13, wherein: The first silicon precursor includes at least one of (dimethylamino)trimethylsilane, bis(dimethylamino)dimethylsilane, N,N-dimethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, N,N-diethyl-2,4,6,8-tetramethyl-cyclotetrasiloxane-2-amine, or a combination thereof.
17. The method according to claim 1, wherein: The second silicon precursor includes aminosilane.
18. The method according to claim 1, wherein: The second silicon precursor includes at least one of the following: DSMA, (SiH3)2NMe; DSEA, (SiH3)2NEt; DSIPA, (SiH3)2N(iPr); DSTBA, (SiH3)2N(tBu); DEAS, SiH3NEt2; DTBAS, SiH3N(tBu)2; BDEAS, SiH2(NEt2)2; BDMAS, SiH2(NMe2)2; BTBAS, SiH2(NHtBu)2; DIPAS, Si H3N(iPr)2; 3DMAS, SiH(N(Me)2)3; BEMAS, SiH2[N(Et)(Me)]2; TEMS, SiH(NEtMe)3; TIPAS, SiH(NHiPr)3; DS, (N(iPr)2)SiH2-SiH2(N(iPr)2); BDEADS, (NEt2)SiH2-SiH2(NEt2); BDPADS, (NPr2)SiH2-SiH2(NPr2) or combinations thereof.
19. The method according to claim 1, wherein: The oxidant includes at least one of oxygen plasma, CO2 plasma, N2O plasma, ozone or a combination thereof.
20. The method according to claim 17, wherein: The plasma is generated by applying between about 30 W and about 200 W of RF power to the reactor either in situ or remotely.
21. The method according to claim 20, wherein: The plasma is generated by applying between about 40 W and about 150 W of RF power to the reactor either in situ or remotely.
22. The method according to claim 1, wherein: The process is carried out at between about 20°C and about 100°C.
23. The method according to claim 1, wherein: The process is carried out at between about 35°C and about 90°C.
24. The method according to claim 1, wherein: The surface of the concave portion includes a hydroxyl group (—OH) and an alkyl group.
25. The method of claim 1, further comprising: forming a barrier film on the silicon oxide film; filling the recess with a conductive film; and Planarize the substrate from the top of the substrate, wherein the barrier layer comprises at least one of Ta, TaN, Ta / TaN, TiN or a mixture thereof; The conductive film includes at least one of copper, tungsten, polysilicon or a mixture thereof.