Semiconductor device manufacturing method and semiconductor device manufacturing system

Abstract

To form a cavity of a desired shape in a recess.SOLUTION: A method for manufacturing a semiconductor device includes a deposition step, a processing step, and a removal step. The deposition step deposits an organic film composed of a polymer including an urea bond in a recess by supplying amine and isocyanate to a surface of a substrate having a recess. The processing step performs predetermined processing for a substrate in which an organic film is deposited in the recess. The removal step removes an organic film in a recess by depolymerizing the organic film by heating the substrate for which the predetermined processing was performed. Amine and isocyanate are a terminal bifunctional straight-chain structure having two functional groups at both ends of the straight-chain structure. At least any of amine and isocyanate has a side chain connected to a straight chain included in the straight-chain structure.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] Various aspects and embodiments of the present disclosure relate to a method and a system for manufacturing a semiconductor device. [Background technology]

[0002] For example, Patent Document 1 below discloses a technology in which an organic film is embedded in a recess formed in a substrate, a sealing film is formed on the recess with the embedded organic film, and the substrate is heated to thermally decompose the organic film through the sealing film, thereby forming an air gap in the recess. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-174915 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a method and system for manufacturing a semiconductor device that can form a cavity of a desired shape in a recess. [Means for solving the problem]

[0005] One aspect of the present disclosure is a method for manufacturing a semiconductor device, including a film-forming step, a processing step, and a removal step. In the film-forming step, an amine and an isocyanate are supplied to a surface of a substrate having a recess, thereby forming an organic film composed of a polymer having a urea bond in the recess. In the processing step, a predetermined process is performed on the substrate on which the organic film has been formed in the recess. In the removal step, the substrate that has been subjected to the predetermined process is heated to depolymerize the organic film, thereby removing the organic film in the recess. In addition, the amine and the isocyanate have a terminally bifunctional linear structure having two functional groups at both ends of the linear structure, and at least one of the amine and the isocyanate has a side chain connected to the linear chain included in the linear structure. [Effects of the Invention]

[0006] According to various aspects and embodiments of the present disclosure, a cavity of a desired shape can be formed within the recess. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a system configuration diagram showing an example of a manufacturing system. [Figure 2] FIG. 2 is a schematic diagram showing an example of a film forming apparatus. [Figure 3] FIG. 3 is a schematic diagram showing an example of a heat treatment apparatus. [Figure 4] FIG. 4 is a schematic diagram showing an example of a plasma processing apparatus. [Figure 5] FIG. 5 is a flowchart showing an example of a method for manufacturing a semiconductor device. [Figure 6] FIG. 6 is a schematic diagram showing an example of a manufacturing process of a semiconductor device. [Figure 7] FIG. 7 is a schematic diagram showing an example of a manufacturing process of a semiconductor device. [Figure 8] FIG. 8 is a schematic diagram showing an example of a manufacturing process of a semiconductor device. [Figure 9] FIG. 9 is a schematic diagram showing an example of a manufacturing process of a semiconductor device. [Figure 10]FIG. 10 is a schematic diagram showing an example of a manufacturing process of a semiconductor device. [Figure 11] FIG. 11 shows an example of a combination of isocyanate and amine that are materials for the organic film. [Figure 12] FIG. 12 is a diagram showing an example of the MDSC measurement results for the organic film of Example 1. [Figure 13] FIG. 13 is a diagram showing an example of the MDSC measurement results for the organic film of Example 2. [Figure 14] FIG. 14 is a diagram showing an example of the MDSC measurement results for the organic film of Example 3. [Figure 15] FIG. 15 is a diagram showing an example of the MDSC measurement results for the organic film of Example 4. [Figure 16] FIG. 16 is a diagram showing an example of the MDSC measurement results for the organic film of Example 5. [Figure 17] FIG. 17 is a diagram showing an example of the MDSC measurement results for the organic film of Comparative Example 1. [Figure 18] FIG. 18 is a diagram showing an example of the MDSC measurement results for the organic film of Comparative Example 2. [Figure 19] FIG. 19 is a diagram showing an example of the molecular structure of the amine of Example 1. [Figure 20] FIG. 20 is a diagram showing an example of the molecular structure of the amine of Example 2. [Figure 21] FIG. 21 is a diagram showing an example of a generalized molecular structure of the amines in Examples 1 and 2. [Figure 22] FIG. 22 is a diagram showing an example of the molecular structure of the amine of Example 3. [Figure 23] FIG. 23 is a diagram showing an example of the molecular structure of the amine of Example 4. [Figure 24] FIG. 24 is a diagram showing an example of the molecular structure of the amine of Example 5. [Figure 25] FIG. 25 is a diagram showing an example of a molecular structure obtained by generalizing the structures of the amines in Examples 3 to 5. [Figure 26]FIG. 26 is a diagram showing an example of the relationship between the substrate temperature and the film formation rate. [Figure 27] FIG. 27 is a diagram showing an example of a molecular structure in which the structures of amines and isocyanates are generalized. [Figure 28] FIG. 28 is a diagram showing an example of the change in mass of an organic film with respect to temperature. [Figure 29] FIG. 29 is a schematic diagram showing another example of the manufacturing process of a semiconductor device. [Figure 30] FIG. 30 is a schematic diagram showing another example of the manufacturing process of a semiconductor device. [Figure 31] FIG. 31 is a schematic diagram showing another example of the manufacturing process of a semiconductor device. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the disclosed semiconductor device manufacturing method and semiconductor device manufacturing system will be described in detail with reference to the drawings. Note that the disclosed semiconductor device manufacturing method and semiconductor device manufacturing system are not limited to the following embodiments.

[0009] When an organic film is formed inside a recess by vapor deposition polymerization, the organic film is formed isotropically not only on the bottom of the recess but also on the sidewalls and opening of the recess. Therefore, if the organic film has low fluidity, the opening of the recess may become blocked before the organic film is fully formed inside the recess, resulting in the formation of voids or seams in the organic film formed in the recess. If voids or seams occur in the organic film in the recess, a film formed in a subsequent process may penetrate into the voids or seams. Therefore, when the organic film is removed in a subsequent process to form a cavity in the recess, the shape of the cavity may differ from the desired shape. As a result, when the cavity is used as an air gap around the wiring, the size of the parasitic capacitance formed by the air gap may differ from the desired size.

[0010] Therefore, the present disclosure provides a technique that can form a cavity of a desired shape in a recess.

[0011] [Configuration of manufacturing system 10] FIG. 1 is a system configuration diagram showing an example of a manufacturing system 10. The manufacturing system 10 includes a film forming apparatus 200, a heat treatment apparatus 300-1, a plasma processing apparatus 400, and a heat treatment apparatus 300-2. The manufacturing system 10 is a multi-chamber type vacuum processing system. The manufacturing system 10 uses the film forming apparatus 200, the heat treatment apparatus 300-1, the plasma processing apparatus 400, and the heat treatment apparatus 300-2 to form an air gap in a substrate W on which elements used in a semiconductor device are formed. The heat treatment apparatuses 300-1 and 300-2 have the same configuration. Note that, hereinafter, the heat treatment apparatuses 300-1 and 300-2 will be collectively referred to as the heat treatment apparatus 300 when they are not distinguished from each other.

[0012] The film forming apparatus 200 deposits a thermally decomposable organic film on the surface of the substrate W in which a recess is formed. In this embodiment, the thermally decomposable organic film is a polymer having a urea bond produced by polymerization of multiple types of monomers. The heat treatment apparatus 300-1 removes the organic film deposited around the recess of the substrate W by heating the substrate W to a first temperature. The plasma treatment apparatus 400 deposits a sealing film on the organic film deposited in the recess of the substrate W using microwave plasma. The heat treatment apparatus 300-2 heats the substrate W to a second temperature higher than the first temperature, thereby thermally decomposing the organic film below the sealing film and detaching the organic film below the sealing film through the sealing film. This forms an air gap between the sealing film and the recess.

[0013] The film forming apparatus 200, the heat treatment apparatus 300-1, the plasma treatment apparatus 400, and the heat treatment apparatus 300-2 are connected to the four side walls of a vacuum transfer chamber 101, which has a heptagonal planar shape, via gate valves G. Three load lock chambers 102 are connected to the other three side walls of the vacuum transfer chamber 101 via gate valves G1. Each of the three load lock chambers 102 is connected to an atmospheric transfer chamber 103 via gate valves G2.

[0014] The vacuum transfer chamber 101 is evacuated by a vacuum pump and maintained at a predetermined vacuum level. A transfer mechanism 106 such as a robot arm is provided inside the vacuum transfer chamber 101. The transfer mechanism 106 transfers substrates W between the film formation apparatus 200, the heat treatment apparatus 300-1, the plasma treatment apparatus 400, the heat treatment apparatus 300-2, and their respective load lock chambers 102. The transfer mechanism 106 has two arms 107a and 107b that can move independently.

[0015] A plurality of ports 105 are provided on the side of the atmospheric transfer chamber 103 for attaching a container (e.g., a FOUP (Front-Opening Unified Pod)) C for accommodating the substrate W. An alignment chamber 104 is also provided on the side wall of the atmospheric transfer chamber 103 for aligning the substrate W. A downflow of clean air is also formed within the atmospheric transfer chamber 103.

[0016] A transfer mechanism 108 such as a robot arm is provided in the atmospheric transfer chamber 103. The transfer mechanism 108 transfers the substrate W between each container C, each load lock chamber 102, and the alignment chamber 104.

[0017] The control device 100 has a memory, a processor, and an input / output interface. The memory stores programs executed by the processor, recipes including conditions for each process, and the like. The processor executes the programs read from the memory and controls each part of the manufacturing system 10 via the input / output interface based on the recipes stored in the memory.

[0018] [Configuration of Film Forming Apparatus 200] 2 is a schematic diagram showing an example of a film formation apparatus 200. The film formation apparatus 200 includes a container 201, an exhaust device 202, a shower head 206, and a mounting table 207. In this embodiment, the film formation apparatus 200 is, for example, a CVD (Chemical Vapor Deposition) apparatus.

[0019] The exhaust device 202 exhausts gas from the container 201. The inside of the container 201 is controlled by the exhaust device 202 to a vacuum atmosphere at a predetermined pressure.

[0020] A plurality of types of raw material monomers are supplied to the container 201 via a shower head 206. In this embodiment, the plurality of types of raw material monomers are, for example, isocyanate and amine. A raw material supply source 203a containing an isocyanate in liquid form is connected to the shower head 206 via a supply pipe 204a. In addition, a raw material supply source 203b containing an amine in liquid form is connected to the shower head 206 via a supply pipe 204b.

[0021] Isocyanate liquid supplied from raw material supply source 203a is vaporized by vaporizer 205a provided in supply pipe 204a. The isocyanate vapor vaporized by vaporizer 205a is introduced into shower head 206, which is a gas discharge unit, via supply pipe 204a. Furthermore, amine liquid supplied from raw material supply source 203b is vaporized by vaporizer 205b provided in supply pipe 204b. The amine vapor vaporized by vaporizer 205b is introduced into shower head 206 via supply pipe 204b.

[0022] The shower head 206 is provided, for example, on the upper part of the container 201, and has a large number of outlet holes formed on the bottom surface thereof. The shower head 206 discharges the isocyanate vapor and the amine vapor introduced via the supply pipes 204a and 204b into the container 201 in a shower-like manner from the separate outlet holes.

[0023] A mounting table 207 having a temperature control mechanism (not shown) is provided within the container 201. A substrate W having a recess formed on its surface is mounted on the mounting table 207. The mounting table 207 uses the temperature control mechanism to control the temperature of the substrate W so that the temperature is suitable for vapor deposition polymerization of the raw material monomers supplied from the raw material supply sources 203a and 203b. The temperature suitable for vapor deposition polymerization can be determined depending on the type of raw material monomer. The temperature suitable for vapor deposition polymerization is, for example, within a range of 60°C to 100°C.

[0024] Using such a film forming apparatus 200, an organic film is deposited on the surface of the substrate W having recesses formed thereon by causing a vapor deposition polymerization reaction of two types of raw material monomers on the surface of the substrate W. When the two types of raw material monomers are isocyanate and amine, a polyurea polymer film is deposited on the surface of the substrate W.

[0025] [Configuration of Heat Treatment Device 300] 3 is a schematic diagram showing an example of a heat treatment apparatus 300. The heat treatment apparatus 300 includes a container 301, an exhaust pipe 302, a supply pipe 303, a mounting table 304, a lamp house 305, and an infrared lamp 306.

[0026] A mounting table 304 on which a substrate W is placed is provided within the container 301. A lamp house 305 is provided at a position opposite to the surface of the mounting table 304 on which the substrate W is placed. An infrared lamp 306 is disposed within the lamp house 305.

[0027] An inert gas is supplied into the container 301 via a supply pipe 303. In this embodiment, the inert gas is, for example, N2 gas.

[0028] With the substrate W placed on the mounting table 304 and inert gas being supplied into the container 301 via the supply pipe 303, the infrared lamp 306 is turned on to heat the substrate W, with an organic film laminated in the recessed portion, to a first temperature. When the organic film laminated in the recessed portion of the substrate W reaches the first temperature, a portion of the surface of the organic film on the substrate W is thermally decomposed into two types of raw material monomers. This removes the organic film laminated around the recessed portion of the substrate W. When the organic film is polyurea, heating the organic film to the first temperature depolymerizes a portion of the organic film into the raw material monomers, isocyanate and amine. In this embodiment, when the organic film is polyurea, the first temperature is, for example, within a range of 230°C to 300°C.

[0029] [Plasma processing apparatus 400] 4 is a schematic diagram showing an example of a plasma processing apparatus 400. The plasma processing apparatus 400 includes a processing container 401 and a microwave output device 404.

[0030] The processing vessel 401 is formed in a substantially cylindrical shape using, for example, aluminum whose surface is anodized, and provides a substantially cylindrical processing space S therein. The processing vessel 401 is safety grounded. The processing vessel 401 has a sidewall 401a and a bottom 401b. The central axis of the sidewall 401a is defined as axis Z. The bottom 401b is provided on the lower end side of the sidewall 401a. The bottom 401b is provided with an exhaust port 401h for exhaust. The upper end of the sidewall 401a is open.

[0031] A dielectric window 407 is provided at the upper end of the side wall 401a, and the opening at the upper end of the side wall 401a is closed from above by the dielectric window 407. The lower surface of the dielectric window 407 faces the processing space S. An O-ring 406 is disposed between the dielectric window 407 and the upper end of the side wall 401a.

[0032] A stage 402 is provided in a processing vessel 401. The stage 402 is provided to face a dielectric window 407 in the direction of the axis Z. The space between the stage 402 and the dielectric window 407 is a processing space S. A substrate W is placed on the stage 402.

[0033] The stage 402 includes a base 402a and an electrostatic chuck 402c. The base 402a is formed in a substantially disk shape from a conductive material such as aluminum. The base 402a is disposed in the processing chamber 401 such that the central axis of the base 402a substantially coincides with the axis Z.

[0034] The base 402a is made of a conductive material and is supported by a cylindrical support 420 extending in a direction along the axis Z. A conductive cylindrical support 421 is provided on the outer periphery of the cylindrical support 420. The cylindrical support 421 extends from the bottom 401b of the processing vessel 401 toward the dielectric window 407 along the outer periphery of the cylindrical support 420. An annular exhaust path 422 is formed between the cylindrical support 421 and the sidewall 401a.

[0035] An annular baffle plate 423 having a plurality of through holes formed in the thickness direction is provided at the top of the exhaust path 422. The above-mentioned exhaust port 401h is provided below the baffle plate 423. An exhaust device 431 having a vacuum pump such as a turbo molecular pump and an automatic pressure control valve is connected to the exhaust port 401h via an exhaust pipe 430. The exhaust device 431 can reduce the pressure in the processing space S to a predetermined vacuum level.

[0036] The base 402a also functions as a radio-frequency electrode. An RF power supply 440 that outputs an RF signal for RF bias is electrically connected to the base 402a via a power feed rod 442 and a matching unit 441. The RF power supply 440 supplies bias power of a predetermined frequency (e.g., 13.56 MHz) suitable for controlling the energy of ions attracted to the substrate W to the base 402a via the matching unit 441 and the power feed rod 442.

[0037] The matching unit 441 contains a matching box for matching the impedance on the RF power supply 440 side with the impedance on the load side, mainly consisting of the electrodes, plasma, and processing vessel 401. The matching box contains a blocking capacitor for generating a self-bias.

[0038] An electrostatic chuck 402c is provided on the upper surface of the base 402a. The electrostatic chuck 402c attracts and holds the substrate W by electrostatic force. The electrostatic chuck 402c has a substantially disc-shaped outer shape and has a heater 402d embedded therein. A heater power supply 450 is electrically connected to the heater 402d via wiring 452 and a switch 451. The heater 402d heats the substrate W placed on the electrostatic chuck 402c with power supplied from the heater power supply 450. An edge ring 402b is provided on the base 402a. The edge ring 402b is arranged to surround the substrate W and the electrostatic chuck 402c. The edge ring 402b is also called a focus ring.

[0039] A flow path 402g is formed inside the base 402a. A coolant is supplied to the flow path 402g from a chiller unit (not shown) via a pipe 460. The coolant supplied to the flow path 402g is returned to the chiller unit via a pipe 461. The coolant, whose temperature is controlled by the chiller unit, circulates through the flow path 402g of the base 402a, thereby controlling the temperature of the base 402a. The temperature of the substrate W on the electrostatic chuck 402c is controlled by the coolant flowing inside the base 402a and the heater 402d in the electrostatic chuck 402c.

[0040] The stage 402 is also provided with a pipe 462 for supplying a heat transfer gas such as He gas between the electrostatic chuck 402c and the substrate W.

[0041] The microwave output device 404 outputs microwaves for exciting the processing gas supplied into the processing chamber 401. The microwave output device 404 generates microwaves with a frequency of, for example, 2.4 GHz.

[0042] The microwave output device 404 is connected to a mode converter 409 via a waveguide 408. The mode converter 409 converts the mode of the microwaves output from the microwave output device 404, and supplies the mode-converted microwaves to the antenna 405 via a coaxial waveguide 410.

[0043] The coaxial waveguide 410 includes an outer conductor 410a and an inner conductor 410b. The outer conductor 410a and the inner conductor 410b have a substantially cylindrical shape and are disposed above the antenna 405 so that the central axes of the outer conductor 410a and the inner conductor 410b substantially coincide with the axis Z.

[0044] The antenna 405 includes a cooling jacket 405a, a dielectric plate 405b, and a slot plate 405c. The slot plate 405c is formed in a substantially circular plate shape from a conductive metal. The slot plate 405c is provided on the upper surface of the dielectric window 407 so that the central axis of the slot plate 405c coincides with the axis Z. A plurality of slot holes are formed in the slot plate 405c. The plurality of slot holes are arranged in pairs around the central axis of the slot plate 405c.

[0045] The dielectric plate 405b is formed in a substantially disk shape from a dielectric material such as quartz. The dielectric plate 405b is placed on the slot plate 405c so that the central axis of the dielectric plate 405b substantially coincides with the axis Z. The cooling jacket 405a is provided on the dielectric plate 405b.

[0046] The cooling jacket 405a is formed of a material having a conductive surface, and a flow path 405e is formed inside the cooling jacket 405a. A refrigerant is supplied into the flow path 405e from a chiller unit (not shown). The lower end of the outer conductor 410a is electrically connected to the upper surface of the cooling jacket 405a. The lower end of the inner conductor 410b is electrically connected to the slot plate 405c through an opening formed in the center of the cooling jacket 405a and the dielectric plate 405b.

[0047] The microwaves propagating through the coaxial waveguide 410 propagate through the dielectric plate 405b and then through the multiple slot holes in the slot plate 405c to the dielectric window 407. The microwaves propagating through the dielectric window 407 are radiated into the processing space S from the bottom surface of the dielectric window 407.

[0048] A gas pipe 411 is provided inside the inner conductor 410b of the coaxial waveguide 410. A through-hole 405d through which the gas pipe 411 can pass is formed in the center of the slot plate 405c. The gas pipe 411 extends through the inside of the inner conductor 410b and is connected to a gas supply unit 412.

[0049] The gas supply unit 412 supplies a process gas for depositing a sealing film on the substrate W to the gas pipe 411. The gas supply unit 412 includes a gas supply source 412a, a valve 412b, and a flow rate controller 412c. The gas supply source 412a supplies the process gas for depositing the sealing film. The process gas includes a nitrogen-containing gas, a silicon-containing gas, and a rare gas. In this embodiment, the nitrogen-containing gas is, for example, NH3 gas or N2 gas, the silicon-containing gas is, for example, SiH4 gas, and the rare gas is, for example, He gas or Ar gas.

[0050] The valve 412b controls the supply and stop of the processing gas from the gas supply source 412a. The flow rate controller 412c is, for example, a mass flow controller, and controls the flow rate of the processing gas from the gas supply source 412a.

[0051] An injector 413 is provided within the dielectric window 407. The injector 413 injects the processing gas supplied via the gas pipe 411 into the processing space S through a through-hole 407h formed in the dielectric window 407. The processing gas injected into the processing space S is excited by microwaves radiated into the processing space S through the dielectric window 407. This converts the processing gas into plasma in the processing space S, and a sealing film is deposited on the substrate W by ions, radicals, and the like contained in the plasma.

[0052] [Method of manufacturing a semiconductor device] Fig. 5 is a flowchart showing an example of a method for manufacturing a semiconductor device. The process illustrated in Fig. 5 is started when a substrate W having a recess 50 formed therein, such as that shown in Fig. 6, is loaded into a film forming apparatus 200 by a transfer mechanism 106. In this embodiment, the aspect ratio of the recess 50 is, for example, 0.5 or more.

[0053] First, an organic film is deposited in the recess 50 by the film deposition apparatus 200 (S10). Step S10 is an example of a film deposition process. In step S10, a thermally decomposable organic film is deposited on the substrate W while the substrate W is heated to a first temperature. The temperature of the substrate W in step S10 is higher than the glass transition temperature of the organic film and lower than 150°C. Specifically, the temperature of the substrate W in step S10 is, for example, within a range of 60°C to 130°C. As a result, an organic film 51 is deposited in and around the recess 50 of the substrate W, as shown in FIG. 7, for example. In step S10, the organic film 51 is isotropically formed not only on the bottom of the recess 50 but also on the sidewalls and openings of the recess 50. However, since the organic film 51 in this embodiment has fluidity at the first temperature, it flows to the bottom of the recess 50. This makes it possible to prevent voids and seams from occurring in the organic film 51 in the recess 50. Then, the substrate W is carried out of the film forming apparatus 200 by the transport mechanism 106 and carried into the heat treatment apparatus 300-1.

[0054] Next, the substrate W is heated by the heat treatment device 300-1, and excess organic film 51 is removed (S11). In step S11, the substrate W is heated by the heat treatment device 300-1 to a temperature in the range of, for example, 230°C to 300°C. As a result, the organic film 51 deposited around the recess 50 is thermally decomposed and removed, as shown in FIG. 8, for example. Then, the substrate W is carried out of the heat treatment device 300-1 by the transfer mechanism 106 and carried into the plasma treatment device 400.

[0055] Next, the plasma processing apparatus 400 deposits a sealing film 52 on the substrate W (S12). Step S12 is an example of a processing step. In step S12, the sealing film 52 is deposited on the substrate W using microwave plasma, for example, as shown in FIG. 9. The process of depositing the sealing film 52 on the substrate W is an example of a predetermined process. Then, the substrate W is unloaded from the plasma processing apparatus 400 by the transport mechanism 106 and loaded into the heat treatment apparatus 300-2.

[0056] Next, the organic film 51 in the recess 50 is removed by the heat treatment device 300-2 (S13). Step S13 is an example of a removal process. In step S13, the substrate W is heated by the heat treatment device 300-2 to a second temperature higher than the first temperature. The second temperature is, for example, 400°C or higher. As a result, the organic film 51 below the sealing film 52 is thermally decomposed and detached through the sealing film 52. As a result, an air gap 53 corresponding to the shape of the organic film 51 is formed below the sealing film 52 in the recess 50, as shown in FIG. 10, for example. Then, the substrate W is transported out of the heat treatment device 300-2 by the transport mechanism 106, and the process shown in this flowchart is completed.

[0057] Steps S10 and S11 may be repeated multiple times in this order, thereby removing the organic film 51 deposited around the recess 50 and increasing the thickness of the organic film 51 inside the recess 50.

[0058] [Example] 11 is a diagram showing an example of a combination of isocyanate and amine that are materials for the organic film 51. In the combinations of Examples 1 to 5 and Comparative Example 1, isocyanates with the same molecular structure are used. In the combinations of Comparative Examples 1 and 2, amines with the same molecular structure are used.

[0059] Fig. 12 is a diagram showing an example of the results of temperature-modulated differential scanning calorimetry (MDSC) measurement of organic film 51 formed by vapor deposition polymerization using the combination of isocyanate and amine in Example 1. As shown in Fig. 12, the glass transition temperature of organic film 51 formed by the combination in Example 1 was approximately -39°C.

[0060] Fig. 13 is a diagram showing an example of the MDSC measurement results of organic film 51 formed by vapor deposition polymerization using the combination of isocyanate and amine in Example 2. As shown in Fig. 13, the glass transition temperature of organic film 51 formed by the combination in Example 2 is approximately -21°C.

[0061] Fig. 14 is a diagram showing an example of the MDSC measurement results of organic film 51 formed by vapor deposition polymerization using the combination of isocyanate and amine in Example 3. As shown in Fig. 14, the glass transition temperature of organic film 51 formed by the combination in Example 3 is approximately -28°C.

[0062] Fig. 15 is a diagram showing an example of the MDSC measurement results of organic film 51 formed by vapor deposition polymerization using the combination of isocyanate and amine in Example 4. As shown in Fig. 15, the glass transition temperature of organic film 51 formed by the combination in Example 4 is approximately -34°C.

[0063] Fig. 16 is a diagram showing an example of the MDSC measurement results of organic film 51 formed by vapor deposition polymerization using the combination of isocyanate and amine in Example 5. As shown in Fig. 16, the glass transition temperature of organic film 51 formed by the combination in Example 5 is approximately -20°C.

[0064] Fig. 17 is a diagram showing an example of the MDSC measurement results of organic film 51 formed by vapor deposition polymerization using the combination of isocyanate and amine in Comparative Example 1. As shown in Fig. 17, the glass transition temperature of organic film 51 formed using the combination in Comparative Example 1 is approximately 160°C.

[0065] Fig. 18 is a diagram showing an example of the MDSC measurement results of organic film 51 formed by vapor deposition polymerization using a combination of isocyanate and amine in Comparative Example 2. As shown in Fig. 18, no glass transition temperature was detected in organic film 51 formed using the combination in Comparative Example 2.

[0066] The amine in this embodiment has a terminally bifunctional linear structure having amino groups, which are functional groups, at both ends of the linear structure, and has a side chain connected to the linear chain contained in the linear structure. For example, as shown in FIG. 19, the amine in Example 1 has a linear chain containing a hydrocarbon, nitrogen atoms connected to both ends of the linear chain, and a side chain containing an alkyl group connected to the nitrogen atom. In the example in FIG. 19, the alkyl group is an ethyl group. In the amine in Example 1, the two functional groups at the ends of the linear chain are secondary amines. Also, in the example in FIG. 19, the side chain is connected to the linear chain via the nitrogen atom contained in the secondary amine.

[0067] The amine in Example 2 has a linear chain containing a hydrocarbon and side chains containing alkyl groups connected to nitrogen atoms at both ends of the linear chain, as shown in Figure 20. In the example in Figure 20, the alkyl groups are methyl groups. In the amine in Example 2, the two functional groups at the ends of the linear chain are secondary amines.

[0068] The structure of the amine in Examples 1 and 2 can be generalized to a molecular structure such as that shown in FIG. 21. Specifically, as shown in FIG. 21, the amine in Examples 1 and 2 has a linear chain containing hydrocarbon, nitrogen atoms connected to both ends of the linear chain, and a side chain containing a substituent X connected to the nitrogen atom. In the example in FIG. 21, the substituent X is an alkyl group such as a methyl group or an ethyl group. In addition, in the example in FIG. 21, the value of n is an integer from 0 to 3.

[0069] The amine in Example 3 has a linear chain containing a hydrocarbon and a nitrogen atom, amino groups attached to both ends of the linear chain, and a side chain containing an alkyl group attached to the nitrogen atom in the linear chain, as shown in Figure 22. In the example of Figure 22, the alkyl group is a methyl group.

[0070] The amine in Example 4 has a linear chain containing a hydrocarbon and a nitrogen atom, nitrogen atoms attached to both ends of the linear chain, side chains containing alkyl groups attached to the nitrogen atoms, and side chains containing alkyl groups attached to the nitrogen atoms in the linear chain, as shown in Figure 23. In the example of Figure 23, the alkyl groups are methyl groups.

[0071] Furthermore, as shown in FIG. 24, for example, the amine in Example 5 has a linear chain containing a hydrocarbon and a nitrogen atom, amino groups connected to both ends of the linear chain, and a side chain containing a hydrogen atom connected to the nitrogen atom contained in the linear chain.

[0072] The structures of the amines in Examples 3 to 5 can be generalized to molecular structures such as those shown in FIG. 25. In the amines in Examples 3 to 5, a side chain is connected to an atom (e.g., a nitrogen atom) contained in a linear chain structure. Specifically, as shown in FIG. 25, the amines in Examples 3 to 5 have a linear chain containing a hydrocarbon and a nitrogen atom, a side chain containing a substituent X connected to a nitrogen atom connected to both ends of the linear chain, and a substituent Y connected to the nitrogen atom contained in the linear chain. In the example in FIG. 25, the substituent X and the substituent Y are hydrogen atoms or alkyl groups such as methyl groups or ethyl groups. In the example in FIG. 25, the value of n is an integer from 1 to 3.

[0073] Here, the glass transition temperature was not detected in the organic film formed using the combination in Comparative Example 2. Therefore, when the organic film formed using the combination in Comparative Example 2 is formed in a recess, it is isotropically laminated on the bottom and side walls of the recess without any fluidity. As a result, when an organic film is formed in a recess with a high aspect ratio, the opening of the recess may be blocked by the organic film before the organic film is formed over the entire interior of the recess, which may result in voids or seams in the organic film formed in the recess.

[0074] In contrast, a glass transition temperature was observed in the organic films formed by vapor deposition polymerization of amine and isocyanate in the combinations of Examples 1 to 5. Therefore, the organic films formed by the combinations of Examples 1 to 5 have fluidity at temperatures higher than the glass transition temperature. In this embodiment, the organic film is formed at a temperature, for example, 60°C to 130°C, which is higher than the glass transition temperature of any of the organic films formed by the combinations of Examples 1 to 5. This allows the fluid organic film to flow into the recess when the organic film is formed in a recess with a high aspect ratio. This makes it possible to prevent voids and seams from occurring in the organic film formed in the recess.

[0075] The glass transition temperature of the organic film formed using the combination in Comparative Example 1 was approximately 160°C. Therefore, even with the combination in Comparative Example 1, it is thought that by heating the substrate W to 160°C or higher, when forming an organic film in a recess with a high aspect ratio, the fluid organic film may flow into the recess. However, if the temperature of the substrate W is high, it becomes difficult for the organic film to be adsorbed onto the substrate W. Therefore, if the temperature of the substrate W is high, the deposition rate of the organic film decreases, and throughput decreases.

[0076] Fig. 26 is a diagram showing an example of the relationship between the temperature of the substrate W and the film formation rate. Fig. 26 shows the experimental results of the film formation rate in the combination of Comparative Example 2, but the tendency of the film formation rate relative to temperature is similar for the organic films formed by the combinations of Examples 1 to 5 and Comparative Example 1. As shown in Fig. 26, the higher the temperature of the substrate W, the lower the film formation rate, and when the temperature of the substrate W reaches 150°C or higher, almost no organic film is formed on the substrate W. Therefore, in the combination of Comparative Example 1, when the substrate W is heated to 160°C or higher, almost no organic film is formed on the substrate W.

[0077] Here, the amine in each combination of Examples 1 to 5 has a molecular structure having a linear chain and a side chain. This suppresses packing between molecules having urea bonds formed by vapor deposition polymerization of the amine and isocyanate. This allows the glass transition temperature of the organic film formed by the combination of Examples 1 to 5 to be lowered. The glass transition temperature of the organic film formed by the combination of Examples 1 to 5 is sufficiently lower than 150°C, as shown in Figure 11, for example.

[0078] In Comparative Example 1, the alicyclic skeleton, which is a cyclic structure, is unlikely to undergo structural change, meaning that the fluidity of the polyurea is low. This is thought to be because Examples 1 to 5 lower the glass transition temperature by reducing the packing between molecules using side chains of the linear aliphatic structure, which is prone to structural change, whereas Comparative Example 1 has a high glass transition temperature regardless of the packing between molecules.

[0079] Therefore, in the combinations of Examples 1 to 5, by forming the organic film at a temperature higher than the glass transition temperature and lower than 150°C (for example, 60°C to 130°C), the organic film can be formed on the substrate W while the organic film has fluidity. This makes it possible to suppress voids and seams formed in the organic film within the recess. This makes it possible to form the cavity after removing the organic film into a desired shape. Furthermore, in the combinations of Examples 1 to 5, even if the temperature is lower than 150°C, the organic film can be formed on the substrate W while the organic film has fluidity as long as it is higher than the glass transition temperature. This makes it possible to form the organic film on the substrate W at a high film formation rate. This makes it possible to improve throughput.

[0080] In the above-described Examples 1 to 5, the amine was specified as having a terminally bifunctional linear structure having amino groups, which are functional groups, at both ends of the linear structure, and a structure having a side chain connected to the linear chain included in the linear structure. However, the disclosed technology is not limited to this. The terminally bifunctional linear structure having functional groups at both ends of the linear structure and having a side chain connected to the linear chain included in the linear structure may be a structure that is possessed by at least one of amine and isocyanate, which are materials for the organic film.

[0081] An example of such a molecular structure is shown in FIG. 27. FIG. 27 is a diagram showing an example of a molecular structure that generalizes the structures of amines and isocyanates. The molecular structure shown in FIG. 27 has a linear chain containing a hydrocarbon, a side chain containing a substituent X connected to carbon atoms at both ends of the linear chain, and a functional group R connected to carbon atoms at both ends of the linear chain. In the example of FIG. 27, the functional group R is an amino group or an isocyanate group. The substituent X is an alkyl group such as a methyl group or an ethyl group. In the example of FIG. 21, the value of n is an integer from 0 to 3.

[0082] In the amine having the structure shown in Figure 27, an amino group is connected to the carbon atom connecting the linear chain and the side chain, and in the isocyanate having the structure shown in Figure 27, an isocyanate group is connected to the carbon atom connecting the linear chain and the side chain.

[0083] Furthermore, the glass transition temperature of the organic film formed in the combination of Examples 1 to 5 described above is 180°C or more lower than that of Comparative Example 1. However, the temperature at which the organic film formed in the combination of Examples 1 to 5 is removed by depolymerization is only several tens of degrees Celsius lower than that of Comparative Example 2. Fig. 28 is a graph showing an example of the change in mass of an organic film with respect to temperature.

[0084] The temperature at which the mass of the organic film is reduced by 90% is approximately 430°C for the organic film formed using the combination of Comparative Example 2, as shown in FIG. 28, for example. On the other hand, the temperature is approximately 370°C for the organic film formed using the combination of Example 1, as shown in FIG. 28, for example. Thus, the temperature at which the organic film formed using the combination of Example 1 is removed by depolymerization is approximately 60°C lower than that of Comparative Example 2. A similar tendency is observed in the organic films formed using the other combinations of Examples 2 to 5. In other words, the organic films formed using the combinations of Examples 1 to 5 also have heat resistance at the same level as the comparative examples.

[0085] The above describes the embodiments. As described above, the semiconductor device manufacturing method in the above-described embodiments includes a film formation process, a treatment process, and a removal process. In the film formation process, an amine and an isocyanate are supplied to the surface of a substrate W having a recess 50, thereby forming an organic film 51 composed of a polymer having a urea bond within the recess 50. In the treatment process, a predetermined treatment is performed on the substrate W on which the organic film 51 has been formed in the recess 50. In the removal process, the substrate W that has been subjected to the predetermined treatment is heated to depolymerize the organic film 51, thereby removing the organic film 51 from within the recess 50. Furthermore, the amine and the isocyanate have a terminally bifunctional linear structure having two functional groups at both ends of the linear structure, and at least one of the amine and the isocyanate has a side chain connected to the linear chain included in the linear structure. This prevents voids and seams from forming in the organic film 51 within the recess 50, and allows the desired shape of the cavity after the organic film 51 is removed.

[0086] In the amine of the above embodiment, the two functional groups at the ends of the linear chain may be secondary amines, and the side chains may be connected to the linear chain via nitrogen atoms contained in the secondary amines. By using an amine with such a molecular structure, it is possible to suppress packing between molecules having urea bonds.

[0087] In the amine or isocyanate of the above-described embodiment, the side chain is connected to an atom contained in the linear chain structure. For example, the side chain is connected to a nitrogen atom contained in the linear chain structure. By using an amine with such a molecular structure, it is possible to suppress packing between molecules having urea bonds.

[0088] Furthermore, the amine of the above embodiment has an amino group connected to the carbon atom connecting the linear chain and the side chain. By using an amine with such a molecular structure, it is possible to suppress packing between molecules having urea bonds.

[0089] The isocyanate of the above embodiment has an isocyanate group connected to the carbon atom connecting the linear chain and the side chain. By using an isocyanate with such a molecular structure, it is possible to suppress packing between molecules having urea bonds.

[0090] Furthermore, in the above-described embodiment, the film formation process is performed at a temperature higher than the glass transition temperature of the organic film 51 and lower than 150° C. This allows the organic film 51 to be formed on the substrate W while the organic film 51 has fluidity, and makes it possible to suppress voids and seams from being formed in the organic film 51 within the recess 50.

[0091] In the above-described embodiment, the aspect ratio of the recess 50 is 0.5 or more. Even in the recess 50 with such an aspect ratio, voids and seams in the organic film 51 formed in the recess 50 can be suppressed by using the amine and isocyanate having the molecular structure shown in this embodiment.

[0092] The semiconductor device manufacturing system according to the embodiment includes a film forming apparatus 200, a heat treatment apparatus 300, and a plasma treatment apparatus 400. The film forming apparatus 200 applies an amine and an isocyanate to the surface of a substrate W having a recess 50, thereby forming an organic film 51 composed of a polymer having a urea bond within the recess 50. The plasma treatment apparatus 400 performs a predetermined process on the substrate W on which the organic film 51 has been formed within the recess 50. The heat treatment apparatus 300 heats the substrate W after the predetermined process to depolymerize the organic film, thereby removing the organic film 51 from within the recess 50. The amine and isocyanate have a terminally bifunctional linear structure having two functional groups at both ends of the linear structure, and at least one of the amine and the isocyanate has a side chain connected to the linear chain included in the linear structure. This prevents voids and seams from forming within the organic film 51 within the recess 50, allowing the desired shape of the cavity remaining after the organic film 51 is removed.

[0093] [others] The technology disclosed in this application is not limited to the above-described embodiment, and various modifications are possible within the scope of the gist thereof.

[0094] For example, in the above-described embodiment, the organic film 51 is formed in the recess 50 of the substrate W, the sealing film 52 is formed thereon, and the substrate W is heated to remove the organic film 51, thereby forming the air gap 53 below the sealing film 52. However, the disclosed technology is not limited to this. In another embodiment, the organic film 51 may be used to form a deep hole.

[0095] For example, as shown in FIG. 29, a recess 50-1 is formed in a film 55-1 to be etched by etching, and an organic film 51 is embedded in the recess 50-1. Then, as shown in FIG. 30, a film 55-2 to be etched is further stacked on the film 55-1, and a recess 50-2 is formed in the film 55-2 by etching. At this time, the organic film 51 in the recess 50-1 is exposed at the bottom of the recess 50-2. Thereafter, by heating the substrate W to a second temperature, the organic film 51 in the recess 50-1 is depolymerized, and the organic film 51 is removed through the recess 50-2. This makes it possible to form a recess with a large aspect ratio, as shown in FIG. 31, for example. Note that the process of stacking a film 55-2 to be etched on the film 55-1 and forming the recess 50-2 in the film 55-2 by etching is an example of a predetermined process.

[0096] It should be noted that the disclosed embodiments are illustrative in all respects and should not be considered limiting. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the appended claims. [Explanation of symbols]

[0097] C container G Gate Valve W substrate 10 Manufacturing Systems 100 control device 101 Vacuum transfer chamber 102 Load Lock Chamber 103 Atmospheric Transfer Chamber 104 Alignment Room Port 105 106 Transport mechanism 107 Arm 108 Transport mechanism 200 Film deposition equipment 300 Heat Treatment Equipment 400 Plasma processing equipment 50 recess 51 Organic film 52 Sealing film 53 Air Gap 55 membrane

Claims

1. a film-forming step of supplying an amine and an isocyanate to a surface of a substrate having a recess, thereby forming an organic film composed of a polymer having a urea bond in the recess; a processing step of performing a predetermined process on the substrate on which the organic film has been formed in the recess; a removing step of removing the organic film in the recess by heating the substrate on which the predetermined treatment has been performed to depolymerize the organic film; Including, the amine and the isocyanate have a terminally difunctional linear structure having two functional groups at both ends of the linear structure; At least one of the amine and the isocyanate has a side chain connected to the linear chain contained in the linear structure.

2. In the amine, the two functional groups at the ends of the linear chain are secondary amines; The method for manufacturing a semiconductor device according to claim 1 , wherein the side chain is connected to the linear chain via a nitrogen atom contained in the secondary amine.

3. The method for manufacturing a semiconductor device according to claim 1 , wherein the side chain is connected to an atom included in the linear chain structure.

4. The method for manufacturing a semiconductor device according to claim 3 , wherein the side chain is connected to a nitrogen atom contained in the linear chain structure.

5. 2. The method for manufacturing a semiconductor device according to claim 1, wherein the amine has an amino group connected to a carbon atom connecting the linear chain and the side chain.

6. 2. The method for manufacturing a semiconductor device according to claim 1, wherein the isocyanate has an isocyanate group connected to a carbon atom connecting the linear chain and the side chain.

7. 2. The method for manufacturing a semiconductor device according to claim 1, wherein the film forming step is performed at a temperature higher than the glass transition temperature of the organic film and lower than 150.degree.

8. 2. The method for manufacturing a semiconductor device according to claim 1, wherein the recess has an aspect ratio of 0.5 or more.

9. a film forming apparatus for supplying an amine and an isocyanate to a surface of a substrate having a recess, thereby forming an organic film composed of a polymer having a urea bond in the recess; a processing device that performs a predetermined process on the substrate on which the organic film has been formed in the recess; a heat treatment device that heats the substrate on which the predetermined treatment has been performed to depolymerize the organic film, thereby removing the organic film in the recess; Equipped with the amine and the isocyanate have a terminally difunctional linear structure having two functional groups at both ends of the linear structure; At least one of the amine and the isocyanate has a side chain connected to the linear chain contained in the linear structure.

10. In the amine, the two functional groups at the ends of the linear chain are secondary amines; The system for manufacturing a semiconductor device according to claim 9 , wherein the side chain is connected to the linear chain via a nitrogen atom contained in the secondary amine.

11. The system for manufacturing a semiconductor device according to claim 9 or 10, wherein the side chain is connected to an atom included in the linear chain structure.

12. The system for manufacturing a semiconductor device according to claim 11 , wherein the side chain is connected to a nitrogen atom contained in the linear chain structure.

13. 10. The system for manufacturing a semiconductor device according to claim 9, wherein the amine has an amino group connected to a carbon atom connecting the linear chain and the side chain.

14. 10. The system for manufacturing a semiconductor device according to claim 9, wherein the isocyanate has an isocyanate group connected to a carbon atom connecting the linear chain and the side chain.

15. 10. The semiconductor device manufacturing system according to claim 9, wherein the film forming device forms the organic film at a temperature higher than the glass transition temperature of the organic film and lower than 150.degree.

16. 10. The semiconductor device manufacturing system according to claim 9, wherein the recess has an aspect ratio of 0.5 or more.

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