Film deposition method and film deposition apparatus

Abstract

To provide a technique for selectively forming a film on a top surface of a convex portion in a substrate surface including adjacent concave and convex portions.SOLUTION: The film forming method includes the following steps. A liquid is supplied to the concave portion of a substrate whose surface includes adjacent concave and convex portions. A processing gas that chemically changes the liquid is supplied to the surface of the substrate, and the liquid is moved from the concave portion to the top surface of the convex portion by a reaction between the processing gas and the liquid, thereby selectively forming a film on the top surface of the convex portion of the substrate surface. The liquid is a liquid halide, a liquid metal, or a liquid polymer or ionic liquid supplied to the concave portion by a spin coating method.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This disclosure relates to a film deposition method and a film deposition apparatus. [Background technology]

[0002] Patent Document 1 discloses a method for selectively forming a film on a specific region of a substrate without using photolithography technology. This method involves selectively forming Si adsorption sites on the flat surface of the substrate, rather than on the flat surface of the substrate or on the wall surface of a trench recessed from the flat surface. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2018-117038 [Overview of the project] [Problems that the invention aims to solve]

[0004] One aspect of this disclosure provides a technique for selectively forming a film on the top surface of a convex portion of a substrate surface that includes adjacent concave and convex portions. [Means for solving the problem]

[0005] A film-forming method according to one aspect of the present disclosure includes the following steps: supplying a liquid to a recess of a substrate having adjacent recesses and protrusions on its surface; supplying a processing gas that chemically alters the liquid to the surface of the substrate, and moving the liquid from the recesses to the top surfaces of the protrusions by reaction between the processing gas and the liquid, thereby selectively forming a film on the top surfaces of the protrusions on the surface of the substrate. The liquid is a liquid halide, a liquid metal, or a liquid polymer or ionic liquid supplied to the recesses by a spin-coating method. [Effects of the Invention]

[0006] According to one aspect of this disclosure, a film can be selectively formed on the top surface of a convex portion among the substrate surface which includes adjacent concave and convex portions. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a flowchart showing a film deposition method according to one embodiment. [Figure 2] Figure 2 is a cross-sectional view showing an example of a substrate, where (A) is a cross-sectional view after step S1 and before step S2, (B) is a cross-sectional view showing partway through step S2, and (C) is a cross-sectional view showing after step S2. [Figure 3] Figure 3 is a cross-sectional view showing a film deposition apparatus according to one embodiment. [Figure 4] Figure 4 is a flowchart showing a modified example of the film deposition method in Figure 1. [Figure 5] Figure 5 shows SEM images of the substrate according to Example 1, where (A) is an SEM image after step S1 and before step S2, (B) is an SEM image taken during step S2, and (C) is an SEM image taken after step S2. [Figure 6] Figure 6 shows SEM images of the substrate according to Example 2, where (A) is an SEM image after step S1 and before S2, and (B) is an SEM image after step S2. [Figure 7] Figure 7 shows the relationship between the processing time in step S4 (Table 2) of Example 3 and the thickness of the liquid in the recess. [Figure 8] Figure 8(A) is an SEM image of the substrate after processing according to Example 4, Figure 8(B) is an SEM image of the substrate after processing according to Example 5, Figure 8(C) is an SEM image of the substrate after processing according to Example 6, and Figure 8(D) is an SEM image of the substrate after processing according to Example 7. [Figure 9] Figure 9(A) is an SEM image of the substrate after processing according to Example 8, Figure 9(B) is an SEM image of the substrate after processing according to Example 9, and Figure 9(C) is an SEM image of the substrate after processing according to Example 10. [Figure 10]Figure 10(A) is an SEM image of the substrate after processing according to Example 11, and Figure 10(B) is an SEM image of the substrate after processing according to Example 12. [Figure 11] Figure 11(A) is an SEM image of the substrate after processing according to Example 13, and Figure 11(B) is an SEM image of the substrate after processing according to Example 14. [Figure 12] Figure 12 is an SEM image of the substrate after processing according to Example 17. [Figure 13] Figure 13 is an SEM image of the substrate after processing according to Example 18. [Modes for carrying out the invention]

[0008] Embodiments of this disclosure will be described below with reference to the drawings. In each drawing, the same or corresponding components are denoted by the same reference numerals, and their descriptions may be omitted.

[0009] Referring to Figure 1, an example of a film deposition method will be described. The film deposition method has steps S1 to S2. In step S1, as shown in Figure 2(A), liquid L is supplied to the recess Wb of the recess Wb and the protrusion Wc that constitute the substrate surface Wa. Liquid L may be supplied directly to the recess Wb, or it may be supplied to the recess Wb from the top surface Wd of the protrusion. In addition, liquid L may overflow from the recess Wb and cover the top surface Wd of the protrusion. The substrate surface Wa includes the bottom surface of the recess, the side surface of the recess, and the top surface Wd of the protrusion. The top surface Wd of the protrusion is a flat surface, and the recess Wb is recessed from the top surface Wd of the protrusion.

[0010] The substrate W includes, for example, a base substrate W1 including a silicon wafer, and a textured film W2 formed on the base substrate W1. The textured film W2 forms recesses Wb and protrusions Wc. The recesses Wb are trenches or via holes, etc. In this embodiment, the recesses Wb penetrate the textured film W2, but they do not have to penetrate. The protrusions Wc may be pillars, etc. In this embodiment, the textured film W2 is an insulating film, but it may be a conductive film or a semiconductor film. However, the recesses Wb and protrusions Wc may be formed on the surface of a silicon wafer.

[0011] The liquid L preferably has strong intermolecular forces. The stronger the intermolecular forces, the stronger the cohesive force. If the cohesive force of the liquid L is large, evaporation of the liquid L can be prevented. The intermolecular force of the liquid L is, for example, 30 kJ / mol or more.

[0012] The liquid L is, for example, a halide. The liquid halide is formed, for example, by the reaction of a raw material gas of the halide and a reaction gas that reacts with the raw material gas. Generation of the liquid L may be promoted by plasmaizing both the raw material gas and the reaction gas, or the reaction gas. The gas is, for example, TiCl4 gas, and the reaction gas is, for example, H2 gas.

[0013] TiCl4 gas and H2 gas are generally used for forming a Ti film rather than forming the liquid L. The Ti film is formed, for example, by a CVD (Chemical Vapor Deposition) method or an ALD (Atomoic Layer Deoposition) method. In the CVD method, TiCl4 gas and H2 gas are simultaneously supplied to the substrate W. On the other hand, in the ALD method, TiCl4 gas and H2 gas are alternately supplied to the substrate W. According to the CVD method or the ALD method, the following formulas (1) to (3) are presumed to contribute to the formation of the Ti film. TiCl4 + H2 → TiH x Cl y ···(1) TiH x Cl y → TiCl2 + HCl ···(2) TiCl2 + H2 → Ti + HCl ···(3) In the above formulas (2) and (3), TiCl2 may be TiCl or TiCl3.

[0014] In the formation of the Ti film, the temperature of the substrate W is controlled to 400°C or more. As a result, the reactions of the above formulas (1) to (3) proceed sequentially, and a Ti film is formed.

[0015] On the other hand, in the formation of liquid L, the temperature of the substrate W is controlled to -100°C to 390°C, preferably 20°C to 350°C. As a result, the reaction of equation (2) and the reaction of equation (3) above are suppressed, so TiH x Cl y A liquid L containing the above is formed. The liquid may contain Ti, TiCl, TiCl2, TiCl3, or TiCl4. The temperature of the substrate W should be lower than the decomposition point of the liquid L.

[0016] Note that the raw material gas is not limited to TiCl4 gas. For example, the raw material gas may be silicon halide gases such as SiCl4 gas, Si2Cl6 gas, SiHCl3 gas, or metal halide gases such as WCl4 gas, VCl4 gas, AlCl3 gas, MoCl5 gas, SnCl4 gas, or GeCl4 gas. The raw material gas only needs to contain a halogen, and instead of chlorine (Cl), it may contain bromine (Br), iodine (I), or fluorine (F), etc. As long as the temperature of the substrate W is low, the reaction will mainly proceed in the same manner as in formula (1) above, and a halide liquid L will be formed.

[0017] Furthermore, the reaction gas is not limited to H2 gas. Any reaction gas capable of forming liquid L through reaction with the source gas is acceptable. For example, the reaction gas may be D2 gas. The reaction gas may also be supplied together with an inert gas such as argon gas.

[0018] Step S1 includes, for example, simultaneously supplying a source gas and a reaction gas to a substrate W. In this case, step S1 may further include plasmaizing both the source gas and the reaction gas. Plasmaization can accelerate the reaction between the source gas and the reaction gas. Plasmaization also facilitates the formation of liquid L at a lower substrate temperature.

[0019] In this embodiment, step S1 includes simultaneously supplying the source gas and reaction gas to the substrate W, but it may also include supplying the source gas and reaction gas alternately to the substrate W. In the latter case, step S1 may further include plasmaizing the reaction gas. Plasmaization can accelerate the reaction between the source gas and the reaction gas. Plasmaization also makes it easier to form liquid L at a lower substrate temperature. Furthermore, step S1 may also include supplying only the source gas to the substrate W.

[0020] Liquid L can be any substance with strong intermolecular forces, and may be an ionic liquid, a liquid metal, or a liquid polymer. The metal may be a pure metal or an alloy. The polymer may be, for example, Si2Cl6 gas, SiCl4 gas, SiHCl3 gas, SiH2Cl2 gas, SiH3Cl gas, SiH4 gas, Si2H6 gas, Si3H8 gas, Si4H 10 The liquid L may be an oligomer or polymer formed by polymerizing two or more molecules of gas, cyclohexasilane gas, tetraethoxysilane (TEOS) gas, dimethyldiethoxysilane (DMDEOS) gas, 2,4,6,8-tetramethylcyclotetrasiloxane (TMCTS) gas, or trisilylamine (TSA) gas, for example, a polysiloxane, polysilane, or polysilazane. The liquid L may also be a silanol or the like. These liquids L are supplied to the recesses Wb of the substrate W by a spin coating method, or synthesized inside a processing container containing the substrate W and supplied to the recesses Wb of the substrate W.

[0021] In step S2, as shown in Figures 2(B) and 2(C), a processing gas G that chemically alters the liquid L is supplied to the substrate surface Wa. The reaction between the processing gas G and the liquid L causes the liquid L to move from the recesses Wb to the top surfaces Wd of the protrusions, selectively forming a film W3 on the top surfaces Wd of the protrusions on the substrate surface Wa. A thin film W3 may also be formed on the sides or bottom surfaces of the recesses. The film W3 may be a solid or a viscous material. The thickness of the film W3 can be controlled by the amount of liquid L supplied and the number of cycles, as described later.

[0022] The processing gas G is supplied, for example, from above the substrate surface Wa, and reacts with the liquid L. The liquid L reacts with the processing gas G and undergoes a chemical change. As the chemical change proceeds gradually from the surface of the liquid L, a difference in surface tension is created, and volume expansion or contraction occurs from the surface of the liquid L, making the liquid L unstable and generating convection. The surface of the liquid L changes into a substance with high surface tension due to the reaction with the processing gas G, so the liquid L moves towards the top surface Wd of the convexity. Furthermore, the volume increase or decrease due to the chemical change on the surface of the liquid L also causes the liquid L to move towards the top surface Wd of the convexity. Finally, the liquid L moves to the top surface Wd of the convexity through its reaction with the processing gas G.

[0023] Furthermore, during the chemical change of liquid L, degassing occurs due to the reaction between liquid L and the processing gas G. The movement of liquid L caused by the degassing is also considered to be a contributing factor to the movement of liquid L. In addition, minute vibrations of the substrate W are also considered to be a contributing factor to the movement of liquid L.

[0024] The processing gas G contains elements that are incorporated into liquid L through a reaction with liquid L. In other words, the processing gas G contains elements that are incorporated into film W3. For example, oxygen from the processing gas G is incorporated into liquid L, resulting in film W3 which is an oxide. Alternatively, nitrogen from the processing gas G is incorporated into liquid L, resulting in film W3 which is a nitride. It is sufficient that elements in the processing gas G are incorporated into liquid L, and in the process, elements constituting liquid L may be degassed.

[0025] For example, the processing gas G contains an oxygen-containing gas. The oxygen-containing gas contains oxygen as an element incorporated into liquid L. The oxygen-containing gas may also contain nitrogen as an element incorporated into liquid L. The oxygen-containing gas includes, for example, O2 gas, O3 gas, H2O gas, NO gas, or N2O gas.

[0026] The processing gas G may contain a nitrogen-containing gas. The nitrogen-containing gas contains nitrogen as an element incorporated into the liquid L. The nitrogen-containing gas includes, for example, N2 gas, NH3 gas, N2H4 gas, or N2H2 gas.

[0027] The processing gas G may contain a hydride gas. The hydride gas contains elements bonded to hydrogen, such as Si, Ge, B, C, or P, as elements incorporated into the liquid L. The hydride gas may include hydrocarbon gases such as SiH4 gas, Si2H6 gas, GeH4 gas, B2H6 gas, C2H4 gas, or PH3 gas.

[0028] The treatment gas G may degasse the elements constituting liquid L by reacting with liquid L. For example, the treatment gas G may contain a reducing gas. The reducing gas may be, for example, hydrogen (H2) gas or deuterium (D2) gas.

[0029] The processing gas G may be supplied together with an inert gas such as argon gas.

[0030] Step S2 may include plasma formation of the treatment gas G. Plasma formation can accelerate the reaction between the treatment gas G and the liquid L.

[0031] In the substrate processing method shown in Figure 1, steps S1 and S2 are performed once, but steps S1 and S2 may be repeated multiple times. The number of times steps S1 and S2 are repeated is also called the cycle number. The thickness of the film W3 can be controlled by the cycle number. The cycle number is predetermined.

[0032] Next, the film deposition apparatus 1 will be described with reference to Figure 3. The film deposition apparatus 1 includes a substantially cylindrical, airtight processing container 2. An exhaust chamber 21 is provided in the center of the bottom wall of the processing container 2. The exhaust chamber 21 has a shape that protrudes downward, for example, a substantially cylindrical shape. An exhaust pipe 22 is connected to the exhaust chamber 21, for example, on the side of the exhaust chamber 21.

[0033] An exhaust section 24 is connected to the exhaust piping 22 via a pressure adjustment section 23. The pressure adjustment section 23 includes a pressure adjustment valve, such as a butterfly valve. The exhaust piping 22 is configured to reduce the pressure inside the processing container 2 by the exhaust section 24. A transport port 25 is provided on the side of the processing container 2. The transport port 25 is opened and closed by a gate valve 26. Substrates W are loaded and unloaded between the processing container 2 and a transport chamber (not shown) through the transport port 25.

[0034] A stage 3 is provided inside the processing container 2. The stage 3 is a holding part that holds the substrate W horizontally with its surface Wa facing upward. The stage 3 is formed in a substantially circular shape in plan view and is supported by a support member 31. A substantially circular recess 32 is formed on the surface of the stage 3 for placing a substrate W with, for example, a diameter of 300 mm. The recess 32 has an inner diameter slightly larger than the diameter of the substrate W. The depth of the recess 32 is set to be, for example, approximately the same as the thickness of the substrate W. The stage 3 is formed of a ceramic material such as aluminum nitride (AlN). Alternatively, the stage 3 may be formed of a metallic material such as nickel (Ni). In addition, a guide ring for guiding the substrate W may be provided on the peripheral edge of the surface of the stage 3 instead of the recess 32.

[0035] Stage 3 has, for example, a grounded lower electrode 33 embedded in it. Below the lower electrode 33, a heating mechanism 34 is embedded. The heating mechanism 34 is powered by a power supply unit (not shown) based on a control signal from the control unit 100, and heats the substrate W placed on Stage 3 to a set temperature. If the entire Stage 3 is made of metal, the entire Stage 3 functions as the lower electrode, so it is not necessary to embed the lower electrode 33 in Stage 3. Stage 3 is provided with a plurality (e.g., 3) of lifting pins 41 for holding and raising and lowering the substrate W placed on Stage 3. The material of the lifting pins 41 may be, for example, ceramics such as alumina (Al2O3) or quartz. The lower ends of the lifting pins 41 are attached to a support plate 42. The support plate 42 is connected to a lifting mechanism 44 provided outside the processing container 2 via a lifting shaft 43.

[0036] The lifting mechanism 44 is installed, for example, at the bottom of the exhaust chamber 21. The bellows 45 is provided between the opening 211 for the lifting shaft 43 formed on the lower surface of the exhaust chamber 21 and the lifting mechanism 44. The shape of the support plate 42 may be such that it can move up and down without interfering with the support member 31 of the stage 3. The lifting pin 41 is configured to move up and down between the upper surface of the stage 3 and the lower surface of the stage 3 by the lifting mechanism 44.

[0037] A gas supply unit 5 is provided on the top wall 27 of the processing container 2 via an insulating member 28. The gas supply unit 5 forms the upper electrode and faces the lower electrode 33. A high-frequency power supply 512 is connected to the gas supply unit 5 via a matching unit 511. By supplying high-frequency power of 450 kHz to 2.45 GHz, preferably 450 kHz to 100 MHz, from the high-frequency power supply 512 to the upper electrode (gas supply unit 5), a high-frequency electric field is generated between the upper electrode (gas supply unit 5) and the lower electrode 33, and a capacitively coupled plasma is generated. The plasma generation unit 51 includes the matching unit 511 and the high-frequency power supply 512. Note that the plasma generation unit 51 is not limited to generating capacitively coupled plasma, but may generate other plasmas such as inductively coupled plasma.

[0038] The gas supply unit 5 includes a hollow gas supply chamber 52. Numerous holes 53 are evenly spaced on the lower surface of the gas supply chamber 52 for distributing and supplying the processing gas into the processing container 2. A heating mechanism 54 is embedded above the gas supply chamber 52 in the gas supply unit 5. The heating mechanism 54 is heated to a set temperature by power supplied from a power supply unit (not shown) based on a control signal from the control unit 100.

[0039] A gas supply passage 6 is provided in the gas supply room 52. The gas supply passage 6 is connected to the gas supply room 52. Upstream of the gas supply passage 6, gas sources G61, G62, G63, and G64 are connected via gas lines L61, L62, L63, and L64, respectively.

[0040] The gas source G61 is a source of TiCl4 gas and is connected to the gas supply line 6 via the gas line L61. The gas line L61 is equipped with a mass flow controller M61, a storage tank T61, and a valve V61 in that order from the gas source G61 side. The mass flow controller M61 controls the flow rate of TiCl4 gas flowing through the gas line L61. The storage tank T61 can store TiCl4 gas supplied from the gas source G61 via the gas line L61 and increase the pressure of the TiCl4 gas in the storage tank T61 when the valve V61 is closed. The valve V61 controls the supply and cut off of TiCl4 gas to the gas supply line 6 by opening and closing.

[0041] Gas source G62 is an Ar gas source and is connected to gas supply line 6 via gas line L62. A mass flow controller M62 and a valve V62 are installed in gas line L62 in this order from the gas source G62 side. The mass flow controller M62 controls the flow rate of Ar gas flowing through gas line L62. Valve V62 supplies and shuts off Ar gas to gas supply line 6 by opening and closing.

[0042] The gas source G63 is an O2 gas source and is connected to the gas supply passage 6 via the gas line L63. The gas line L63 is equipped with a mass flow controller M63 and a valve V63 in that order from the gas source G63 side. The mass flow controller M63 controls the flow rate of O2 gas flowing through the gas line L63. The valve V63 opens and closes to supply and shut off O2 gas to the gas supply passage 6.

[0043] Gas source G64 is an H2 gas source and is connected to gas supply line 6 via gas line L64. Gas line L64 is equipped with a mass flow controller M64 and a valve V64 in that order from the gas source G64 side. The mass flow controller M64 controls the flow rate of H2 gas flowing through gas line L64. Valve V64 controls the supply and cut off of H2 gas to gas supply line 6 by opening and closing.

[0044] The film forming apparatus 1 includes a control unit 100 and a storage unit 101. The control unit 100 includes a CPU, a RAM, a ROM, etc. (none of which are shown in the figures), and comprehensively controls the film forming apparatus 1 by causing the CPU to execute a computer program stored in, for example, the ROM or the storage unit 101. Specifically, the control unit 100 causes the CPU to execute the control program stored in the storage unit 101 to control the operations of the respective components of the film forming apparatus 1, thereby performing a film forming process or the like on the substrate W.

[0045] Next, referring to FIG. 3 again, the operation of the film forming apparatus 1 will be described. First, the control unit 100 opens the gate valve 26 and conveys the substrate W into the processing chamber 2 by the conveyance mechanism, and places it on the stage 3. The substrate W is placed horizontally with the surface Wa facing upward. After retreating the conveyance mechanism from the inside of the processing chamber 2, the control unit 100 closes the gate valve 26. Next, the control unit 100 heats the substrate W to a predetermined temperature by the heating mechanism 34 of the stage 3, and adjusts the inside of the processing chamber 2 to a predetermined pressure by the pressure adjustment unit 23.

[0046] Next, in step S1 of FIG. 1, the control unit 100 opens the valves V61, V62, V64, and simultaneously supplies TiCl4 gas, Ar gas, and H2 gas into the processing chamber 2. The valve V63 is closed. Due to the reaction between the TiCl4 gas and the H2 gas, a liquid L such as TiH x Cl y is supplied to the concave portion Wb of the substrate W.

[0047] The specific processing conditions in step S1 are as follows, for example. Flow rate of TiCl4 gas: 1 sccm to 100 sccm Flow rate of Ar gas: 10 sccm to 100000 sccm, preferably 100 sccm to 20000 sccm Flow rate of H2 gas: 1 sccm to 50000 sccm, preferably 10 sccm to 10000 sccm Processing time: 1 second to 1800 seconds Processing temperature: -100°C to 390°C, preferably 20°C to 350°C Processing pressure: 0.1 Pa to 10000 Pa, preferably 0.1 Pa to 2000 Pa.

[0048] In step S1, the control unit 100 may generate plasma using the plasma generation unit 51 to promote the reaction between TiCl4 gas and H2 gas. If TiCl4 gas and H2 gas are supplied simultaneously, the control unit 100 will plasmaize both TiCl4 gas and H2 gas.

[0049] In step S1, the control unit 100 may supply TiCl4 gas and H2 gas alternately to the processing container 2 instead of supplying them simultaneously. In this case, the control unit 100 may plasmaize only the H2 gas out of the TiCl4 gas and H2 gas.

[0050] After step S1, valves V61 and V64 are closed. At this time, valve V62 is open, so Ar is supplied into the processing container 2, the gas remaining in the processing container 2 is discharged to the exhaust pipe 22, and the atmosphere inside the processing container 2 is replaced with an Ar atmosphere.

[0051] Next, in step S2 of Figure 1, the control unit 100 opens valve V63 and supplies O2 gas together with Ar gas into the processing container 2. Due to the reaction between the O2 gas and liquid L, liquid L moves from the recess Wb to the top surface Wd of the convex portion, and a film W3 is selectively formed on the top surface Wd of the convex portion.

[0052] The specific processing conditions for step S2 are as follows, for example: O2 gas flow rate: 1 sccm to 100,000 sccm, preferably 1 sccm to 10,000 sccm Ar gas flow rate: 10 sccm to 100,000 sccm, preferably 100 sccm to 20,000 sccm Processing time: 1 second to 1800 seconds Processing temperature: -100°C to 390°C, preferably 20°C to 350°C Processing pressure: 0.1 Pa to 10000 Pa, preferably 0.1 Pa to 2000 Pa.

[0053] In step S2, the control unit 100 may generate plasma using the plasma generation unit 51 to promote the reaction between the O2 gas and the liquid L.

[0054] After step S2, the control unit 100 removes the substrate W from the processing container 2 in the reverse order of loading the substrate W into the processing container 2. The control unit 100 may repeat steps S1 and S2 a predetermined number of times.

[0055] Next, a modified version of the film formation method will be described with reference to Figure 4. This modified version of the film formation method includes step S3 in addition to steps S1 and S2 shown in Figure 1. In step S3, the film W3 formed in step S2 is modified. The modified film W3 has superior chemical resistance compared to the film W3 before modification. For example, the modified film W3 has a lower etching rate to dilute hydrofluoric acid (DHF) compared to the film W3 before modification.

[0056] The modification of the membrane W3 includes, for example, at least one of the following (A) to (B): (A) reducing halogen or hydrogen elements in the membrane W3; (B) increasing the density of the membrane W3. Increasing the density of the membrane W3 can be achieved, for example, by terminating the unbonded ends of the membrane W3 with elements contained in the reformed gas, or by promoting bonding between existing elements in the membrane W3.

[0057] In step S3, a reforming gas may be supplied to the membrane W3. If the reforming gas in S3 and the processing gas G in S2 are the same gas, they are supplied under different conditions. Specifically, for example, the reforming gas may be plasma-activated while the processing gas G is not. Alternatively, the reforming gas may be supplied at a higher temperature or pressure than the processing gas G.

[0058] However, the reformed gas S3 and the treatment gas G S2 may be different gases. For example, the treatment gas G may be nitrogen gas that is plasma-treated, while the reformed gas may be ammonia (NH3) gas that is plasma-treated, or hydrazine (N2H4) gas. Alternatively, the treatment gas G may be oxygen (O2) gas, while the treatment gas G may be ozone (O3) gas, or water vapor (H2O).

[0059] In step S2, the liquid L is moved to the top surface Wd of the protrusion, and in step S3, the film W3 is made to the desired performance. The control unit 100 may repeat steps S1 to S3 a predetermined number of times.

[0060] [Examples] Next, we will describe some examples.

[0061] <Examples 1-2> In Examples 1 and 2, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3, under the processing conditions shown in Table 1.

[0062] [Table 1]

[0063] In Table 1, "Convex Top Surface" refers to the material of the convex top surface Wd, which is the material of the uneven film W2. The material of the concave side surface is the same as the material of the convex top surface Wd. "Concealed Bottom Surface" refers to the material of the concave bottom surface, which is the material of the upper surface of the base substrate W1. Furthermore, "〇" for each gas indicates that the gas was supplied, and "ON" for "RF" indicates that the gas was plasma-generated by high-frequency power. In addition, "Cycle Count" is the number of repetitions of steps S1 and S2. The same applies to Tables 2 to 8 described later.

[0064] Figure 5 shows an SEM image of the substrate W-1 according to Example 1. As shown in Figure 5(A), liquid L-1 was supplied to the recess Wb-1 in step S1. The amount of liquid L-1 supplied was sufficient to fit inside the recess Wb-1. Furthermore, as shown in Figure 5(B), when the process was interrupted midway through step S2, specifically when the processing time for step S2 was 10 seconds, the same behavior as in Figure 2(B) was observed, that is, liquid L-1 crawled up from the recess Wb-1 toward the top surface Wd-1 of the protrusion. In addition, as shown in Figure 5(C), a film W3-1 was selectively formed on the top surface Wd-1 of the protrusion in step S2.

[0065] Figure 6 shows an SEM image of the substrate W-2 according to Example 2. As shown in Figure 6(A), in step S1, liquid L-2 was supplied to the recess Wb-2. In Example 2, the processing time of step S1 was longer and the amount of liquid L-2 supplied was greater than in Example 1, so liquid L-2 was supplied not only to the recess Wb-2 but also to the top surface Wd-2 of the convex portion. Furthermore, as shown in Figure 6(B), in step S2, a film W3-2 was selectively formed on the top surface Wd-2 of the convex portion.

[0066] <Example 3> In Example 3, using the film deposition apparatus 1 shown in Figure 3, step S1 was performed under the processing conditions shown in Table 2. Then, without performing step S2, step S4 was performed under the processing conditions shown in Table 2. In step S4, only Ar gas was supplied into the processing container 2, and the change in liquid L in the recess Wb was observed.

[0067] [Table 2]

[0068] Figure 7 shows the relationship between the processing time of step S4 in Example 3 and the thickness of liquid L in the recess Wb. As is clear from Figure 7, no movement or decrease of liquid L in the recess Wb was observed even when left for a long time under a reduced pressure atmosphere. This means that movement of liquid L does not occur until the reaction between liquid L and processing gas G begins, and that liquid L is difficult to evaporate due to strong intermolecular forces and cohesive forces.

[0069] <Examples 4-7> In Examples 4-7, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3, under the processing conditions shown in Table 3.

[0070] [Table 3]

[0071] Figure 8(A) shows an SEM image of substrate W-4 after processing according to Example 4. In Example 4, steps S1 and S2 were performed once each, similar to Example 1. As a result, film W3-4 was selectively formed on the top surface Wd-4 of the convex portion, rather than on the recess Wb-4.

[0072] Figure 8(B) shows an SEM image of the substrate W-5 after processing according to Example 5. Unlike Example 1, in Example 5, steps S1 and S2 were performed 10 times each. As a result, the film W3-5 was selectively formed on the convex top surface Wd-5 of the recessed Wb-5 and the convex top surface Wd-5.

[0073] Figure 8(C) shows an SEM image of the substrate W-6 after processing according to Example 6. In Example 6, unlike Example 1, H2O gas was supplied to the processing container 2 instead of O2 gas in step S2. As a result, the film W3-6 was selectively formed on the convex top surface Wd-6 of the recess Wb-6 and the convex top surface Wd-6.

[0074] Figure 8(D) shows an SEM image of the substrate W-7 after processing according to Example 7. In Example 7, unlike Example 1, N2 gas was supplied to the processing container 2 instead of O2 gas in step S2. The N2 gas was also plasma-generated. As a result, the film W3-7 was selectively formed on the convex top surface Wd-7 of the recess Wb-7 and the convex top surface Wd-7.

[0075] As is clear from Examples 4 to 7, a film W3 could be selectively formed on the top surface Wd of the convex portion using various types of processing gas G.

[0076] <Examples 8-12> In Examples 8 to 12, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3, under the processing conditions shown in Table 4.

[0077] [Table 4]

[0078] Figure 9(A) shows an SEM image of substrate W-8 after processing according to Example 8. In Example 8, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the material of the top surface of the convex portion and the bottom surface of the concave portion was changed to titanium oxide (TiO2). As a result, film W3-8 was selectively formed on the top surface of the convex portion Wd-8, rather than on the concave portion Wb-8.

[0079] Figure 9(B) shows an SEM image of substrate W-9 after processing according to Example 9. In Example 9, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the material of the top surface of the convex portion and the bottom surface of the concave portion was changed to silicon nitride (SiN). As a result, film W3-9 was selectively formed on the top surface of the convex portion Wd-9, rather than on the concave portion Wb-9.

[0080] Figure 9(C) shows an SEM image of the substrate W-10 after processing according to Example 10. In Example 10, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the material of the top surface of the convex portion and the bottom surface of the concave portion was changed to silicon (Si). As a result, the film W3-10 was selectively formed on the top surface of the convex portion Wd-10, rather than on the concave portion Wb-10.

[0081] Figure 10(A) shows an SEM image of the substrate W-11 after processing according to Example 11. In Example 11, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the material of the top surface of the convex portion and the bottom surface of the concave portion was changed to carbon (C). As a result, the film W3-11 was selectively formed on the top surface of the convex portion Wd-11, rather than on the concave portion Wb-11.

[0082] Figure 10(B) shows an SEM image of the substrate W-12 after processing according to Example 12. In Example 12, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the material of the top surface of the protrusion was changed to ruthenium (Ru). As a result, the film W3-12 was selectively formed on the top surface of the protrusion Wd-12, rather than on the recessed surface Wb-12.

[0083] As is clear from Examples 8 to 12, a film W3 could be selectively formed on the top surface Wd of the convex portion using substrates W made of various materials.

[0084] <Examples 13-14> In Examples 13 and 14, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3, under the processing conditions shown in Table 5.

[0085] [Table 5]

[0086] Figure 11(A) shows an SEM image of substrate W-13 after processing according to Example 13. In Example 13, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the substrate temperature was changed to 80°C. As a result, film W3-13 was selectively formed on the convex top surface Wd-13 of the recessed Wb-13 and the convex top surface Wd-13.

[0087] Figure 11(B) shows an SEM image of the substrate W-14 after processing according to Example 14. In Example 14, steps S1 and S2 were performed once each under the same conditions as in Example 4, except that the substrate temperature was changed to 200°C. As a result, the film W3-14 was selectively formed on the convex top surface Wd-14, rather than on the recessed Wb-14.

[0088] As is clear from Examples 13-14, the film W3 could be selectively formed on the top surface Wd of the convex portion at various substrate temperatures.

[0089] <Examples 15-16> In Example 15, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3 under the processing conditions shown in Table 6. On the other hand, in Example 16, steps S1 to S3 were performed using the film deposition apparatus 1 shown in Figure 3 under the processing conditions shown in Table 6.

[0090] [Table 6]

[0091] In Example 15, when the film W3 formed on the top surface Wd of the convex portion was etched with an aqueous solution with an HF concentration of 0.5 mass%, the etching rate was 762.8 Å / min. On the other hand, when the film W3 formed on the top surface Wd of the convex portion in Example 16 was etched with an aqueous solution with an HF concentration of 0.5 mass%, the etching rate was 81.3 Å / min. Therefore, the film W3 was modified by step S3.

[0092] <Example 17> In Example 17, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3, under the processing conditions shown in Table 7.

[0093] [Table 7]

[0094] Figure 12 shows an SEM image of substrate W-17 after processing according to Example 17. In Example 17, unlike Example 1, in step S1, Si2Cl6 (HCD) was supplied to the processing container 2 as the raw material gas instead of TiCl4. Also, in step S2, Ar gas and O2 gas were plasma-generated. Steps S1 and S2 were performed twice each. Furthermore, the material of the top surface of the convex portion and the bottom surface of the concave portion was changed to TiO2. As a result, of the concave portion Wb-17 and the top surface of the convex portion Wd-17, the film W3-17 was selectively formed on the top surface of the convex portion Wd-17. Similar results were obtained when the material of the top surface of the convex portion and the bottom surface of the concave portion was changed to SiO2.

[0095] <Example 18> In Example 18, steps S1 and S2 were performed using the film deposition apparatus 1 shown in Figure 3, under the processing conditions shown in Table 8.

[0096] [Table 8]

[0097] Figure 13 shows an SEM image of the substrate W-18 after processing according to Example 18. In Example 18, unlike Example 1, in step S1, SnCl4 was supplied to the processing container 2 as the raw material gas instead of TiCl4. As a result, the film W3-18 was selectively formed on the convex top surface Wd-18 of the concave Wb-18 and convex top surface Wd-18.

[0098] As is clear from Examples 17-18, a film W3 could be selectively formed on the top surface Wd of the convex portion using various source gases.

[0099] While embodiments of the film deposition method and film deposition apparatus relating to this disclosure have been described above, this disclosure is not limited to the above embodiments. Various changes, modifications, substitutions, additions, deletions, and combinations are possible within the scope of the claims. These, too, naturally fall within the technical scope of this disclosure. [Explanation of symbols]

[0100] W board Wa surface Wb recess Wc protrusion Wd convex top surface W3 membrane L liquid

Claims

1. The process involves supplying liquid to the recesses of a substrate whose surface includes adjacent recesses and protrusions, The process involves supplying a processing gas that chemically alters the liquid to the surface of the substrate, moving the liquid from the recess to the top surface of the protrusion through a reaction between the processing gas and the liquid, and selectively forming a film on the top surface of the protrusion on the surface of the substrate. A method for forming a film, wherein the liquid is a liquid halide, a liquid metal, or a liquid polymer or ionic liquid supplied to the recess by a spin coating method.

2. The aforementioned liquid is a liquid halide, The method for forming a film according to claim 1, wherein supplying the liquid to the recess is to form the liquid by a reaction between the source gas of the halide and a reaction gas that reacts with the source gas.

3. Supplying the liquid into the recess means When the raw material gas and the reaction gas are supplied simultaneously, the process includes plasma formation of both the raw material gas and the reaction gas. The film formation method according to claim 2, further comprising plasma formation of the reaction gas when the raw material gas and the reaction gas are supplied alternately.

4. The film-forming method according to any one of claims 1 to 3, wherein the processing gas that chemically alters the liquid contains elements that are incorporated into the liquid.

5. The film-forming method according to claim 4, wherein the processing gas used to chemically change the liquid includes an oxygen-containing gas.

6. The film-forming method according to claim 4, wherein the processing gas used to chemically change the liquid includes a nitrogen-containing gas.

7. The film-forming method according to claim 4, wherein the processing gas used to chemically change the liquid includes a hydride gas.

8. The method for forming a film according to claim 7, wherein the hydride comprises Si, Ge, B, C, or P.

9. The film-forming method according to any one of claims 1 to 3, wherein the processing gas that chemically alters the liquid degasses the elements constituting the liquid.

10. The film-forming method according to claim 9, wherein the processing gas used to chemically change the liquid includes a reducing gas.

11. The method for forming a film according to claim 10, wherein the reducing gas is hydrogen gas or deuterium gas.

12. The method for forming a film according to any one of claims 1 to 11, wherein selectively forming the film on the top surface of the convex portion includes plasma-forming the processing gas that chemically alters the liquid.

13. A method for forming a film according to any one of claims 1 to 12, comprising repeatedly supplying the liquid to the recess and selectively forming the film on the top surface of the protrusion.

14. The method for forming a film according to any one of claims 1 to 13, further comprising modifying the film formed on the top surface of the convex portion.

15. The film-forming method according to any one of claims 1 to 14, wherein when the liquid is supplied to the recess, the temperature of the substrate is lower than the decomposition point of the liquid.

16. Processing container and Inside the processing container, there is a holding part that holds the substrate horizontally with the surface including the recess and protrusion facing upward, A gas supply unit supplies a raw material gas, a reaction gas that reacts with the raw material gas, and a processing gas that chemically alters the liquid formed by the reaction between the raw material gas and the reaction gas to the surface of the substrate held by the holding unit. It includes a control unit that controls the gas supply unit, The control unit, The liquid formed by the reaction between the raw material gas and the reaction gas is supplied to the recess of the substrate, The process gas is supplied to the surface of the substrate, and the reaction between the process gas and the liquid causes the liquid to move from the recess to the top surface of the protrusion, thereby selectively forming a film on the top surface of the protrusion on the surface of the substrate. We will implement the following: A film-forming apparatus in which the liquid is a liquid halide or a liquid metal.

17. Processing container and Inside the processing container, there is a holding part that holds the substrate horizontally with the surface including the recess and protrusion facing upward, A gas supply unit supplies a processing gas to the surface of the substrate held by the holding unit, which chemically alters the liquid previously supplied to the recess by a spin coating method, It includes a control unit that controls the gas supply unit, The control unit, The substrate, which has had the liquid supplied to the recesses in advance by a spin coating method, is held in the holding part, The process gas is supplied to the surface of the substrate, and the reaction between the process gas and the liquid causes the liquid to move from the recess to the top surface of the protrusion, thereby selectively forming a film on the top surface of the protrusion on the surface of the substrate. We will implement the following: The aforementioned liquid is a liquid polymer or an ionic liquid, in a film-forming apparatus.

18. The film deposition apparatus according to claim 16 or 17, further comprising a plasma generation unit that generates plasma inside the processing vessel.

Images