JP6216404B2 - Substrate processing method - Google Patents

Description

  The present invention relates to a substrate processing method for processing a silicon substrate as a pre-process for forming a silicon germanium film on a silicon substrate.

  In recent years, in the formation of a transistor on a silicon substrate, a silicon germanium (SiGe) film is formed in the vicinity of a silicon layer serving as a channel portion to cause distortion in the silicon layer. A transistor in which a layer is distorted can operate at high speed.

  Patent Document 1 discloses a technique for recovering the characteristics of a low dielectric constant film by recovering the damage in a substrate damaged by a dry process. In this method, the reaction product generated on the substrate in the cleaning unit is removed, and the silylation process is performed by supplying the silylated material to the substrate in the silylation unit.

JP 2006-86411 A

  By the way, as a pre-process for forming a silicon germanium film on a silicon substrate, a process of removing a natural oxide film (that is, a silicon oxide film) on the silicon substrate is performed. After the silicon oxide film is removed, a silicon germanium film is formed. Since the silicon oxide film grows on the silicon substrate, the time from the completion of the process of removing the silicon oxide film to the start of the process related to the formation of the silicon germanium film (hereinafter referred to as “Q time”). Need to be strictly managed. Here, the current Q time is, for example, 2 to 4 hours, and such a short Q time hinders improvement in productivity of semiconductor products. Further, in the step relating to the formation of the silicon germanium film, prebaking is performed to remove oxygen components and the like adhering to the silicon substrate, but at present, it is necessary to set the prebaking temperature to, for example, 800 ° C., This affects the electrical characteristics of semiconductor products.

  The present invention has been made in view of the above problems, and aims to increase the Q time from the removal of the silicon oxide film to the formation of the silicon germanium film and to lower the pre-baking temperature in the formation of the silicon germanium film. Yes.

The invention according to claim 1 is a substrate processing method for processing the silicon substrate as a pre-process for forming a silicon germanium film on the silicon substrate, wherein a) a silicon oxide film on one main surface of the silicon substrate is formed. A step of removing, and b) a step performed after the step a), in which the silicon oxide film is formed by the step a) by applying a silylation material to the main surface. A step of bringing the removed main surface into a state in which the growth of a natural oxide film is suppressed, and the step a) includes a1) applying a removing solution for removing the silicon oxide film to the main surface. If, a2) a step of applying a rinse liquid to the main surface, wherein b) step is Ru performed following the a2) step.
According to a second aspect of the invention, there is provided a substrate processing method according to claim 1, before Symbol a1) step, the oxygen concentration is performed under an atmosphere that is adjusted to 100ppm or less.

According to a third aspect of the invention, there is provided a substrate processing method according to claim 1 or 2, the oxygen concentration in at least one of the previous SL-removing liquid and the rinsing liquid is reduced to less than 20 ppb.
Invention of Claim 4 is the substrate processing method in any one of Claim 1 thru | or 3, Comprising: In said b) process, TMSI which is silylated material, BSTFA, BSA, MSTFA, TMSDMA, TMSDEA, MTMSA, TMCS, or HMDS is applied to the main surface.

The invention according to claim 5 is the substrate processing method according to any one of claims 1 to 4 , wherein a pattern for a transistor is formed on the silicon substrate.

  According to the present invention, it is possible to lengthen the Q time from the removal of the silicon oxide film to the formation of the silicon germanium film, and to lower the prebaking temperature in the formation of the silicon germanium film.

In the invention of claim 3 , the Q-time can be made longer and the pre-baking temperature can be made lower.

It is a figure which shows the structure of the substrate processing apparatus which concerns on 1st Embodiment. It is a figure which shows the structure of an oxide film removal part. It is a figure which shows the structure of a process liquid supply part. It is a figure which shows the structure of a supply pipe | tube. It is a figure which shows the structure of a silylation process part. It is a figure which shows the silylation process part by which processing space was open | released. It is a figure which shows the pattern formed on the board | substrate. It is a figure which shows the flow of the operation | movement which processes a board | substrate. It is a figure which shows the pattern on a board | substrate. It is a figure which shows the pattern on a board | substrate. It is a figure which shows chemical bond energy. It is a figure which shows the pattern on a board | substrate. It is a figure which shows the change of the thickness of the natural oxide film on a board | substrate. It is a figure which shows the oxygen concentration in a silicon germanium film | membrane. It is a figure which shows the other example of a silylation process part. It is a figure which shows the structure of the substrate processing apparatus which concerns on 2nd Embodiment. It is a figure which shows the structure of a processing unit. It is a figure which shows the lower end of an inlet tube. It is a figure which shows the other example of a processing unit. It is a figure which shows the structure of the substrate processing apparatus which concerns on 3rd Embodiment. It is a figure which shows the structure of a steam processing part. It is a figure which shows the structure of the substrate processing apparatus which concerns on 4th Embodiment. It is a figure which shows the structure of a steam processing part. It is a figure which shows the structure of the substrate processing apparatus which concerns on 5th Embodiment.

  FIG. 1 is a diagram showing a configuration of a substrate processing apparatus 1 according to a first embodiment of the present invention. The substrate processing apparatus 1 is a single-wafer type apparatus that processes a circular silicon substrate (hereinafter simply referred to as “substrate”) 9 with a predetermined chemical solution, rinse solution, or the like. The substrate processing apparatus 1 includes an indexer block 2, a processing block 3, and a control unit 10, and each component of the indexer block 2 and the processing block 3 is controlled by the control unit 10.

  The indexer block 2 includes a carrier holding unit 21 that holds the carrier 90, an indexer robot 22 that is disposed between the carrier holding unit 21 and the processing block 3, and an indexer that moves the indexer robot 22 in the vertical direction in FIG. A robot moving mechanism 23 is provided. In the carrier holding unit 21, a plurality of carriers 90 are arranged along the vertical direction in FIG. 1 (that is, the moving direction of the indexer robot 22), and a plurality of substrates 9 are accommodated in each carrier 90. In the indexer robot 22, the substrate 9 is unloaded from the carrier 90 and the substrate 9 is loaded into the carrier 90.

The processing block 3 includes two oxide film removing units 4, two silylation processing units 6, and a center robot 31. The two oxide film removing units 4 and the two silylation processing units 6 are arranged so as to surround the center robot 31, and the substrate 9 is transferred in the processing block 3 by the center robot 31. As will be described later, the oxide film removing unit 4 removes the silicon oxide film (SiO ₂ ) on one main surface of the substrate 9, and the silylation processing unit 6 performs silylation treatment on the main surface. Is done.

  FIG. 2 is a diagram illustrating a configuration of the oxide film removing unit 4. The oxide film removal unit 4 includes a spin chuck 41 that holds the substrate 9 in a horizontal state, a cup unit 42 that surrounds the spin chuck 41, and a treatment liquid that removes the silicon oxide film (hereinafter referred to as “removal liquid”). A removal liquid nozzle 43 for applying to the substrate 9 and a rinsing liquid nozzle 44 for applying a rinsing liquid to the substrate 9 are provided. The spin chuck 41, the cup part 42, the removal liquid nozzle 43 and the rinsing liquid nozzle 44 are provided in the chamber body 40. Further, the spin chuck 41 can be rotated around an axis parallel to the vertical direction by a spin motor 411.

  The removal liquid nozzle 43 moves not shown between a supply position above the spin chuck 41 and a standby position outside the cup part 42 (that is, a position not overlapping the cup part 42 in the vertical direction). It can be moved by the mechanism. Similarly, the rinsing liquid nozzle 44 can be moved by a moving mechanism (not shown) between a supply position above the spin chuck 41 and a standby position outside the cup portion 42. The treatment liquid supply unit 5 is connected to the removal liquid nozzle 43 and the rinse liquid nozzle 44.

FIG. 3 is a diagram illustrating a configuration of the processing liquid supply unit 5. The treatment liquid supply unit 5 includes an inert gas dissolved water generation unit 51 that degass oxygen in pure water and adds an inert gas to the pure water to generate inert gas dissolved water. The inert gas dissolved water generation unit 51 degasses oxygen until the oxygen concentration in the supplied pure water is, for example, 20 ppb (parts per virion) or less, and high-purity nitrogen (N ₂ ) gas. (For example, nitrogen gas having a concentration of 99.999% to 99.99999999999%) is added to pure water to generate an inert gas-dissolved water having a nitrogen concentration of, for example, 7 ppm (parts per million) to 24 ppm.

  The treatment liquid supply unit 5 includes a preparation unit 52 that mixes a stock solution of the removal solution and inert gas-dissolved water to prepare the removal solution, and a stock solution supply unit 53 that supplies the preparation solution to the preparation unit 52. The stock solution supply unit 53 includes a tank 532 that stores a stock solution of the removal solution, and the tank 532 is connected to the preparation unit 52 via a supply pipe 531. The tank 532 is a sealed container, and the internal space of the tank 532 is blocked from the outside. The supply pipe 531 is provided with a pump 533, a filter 534, and a deaeration unit 535 in order from the tank 532 side toward the blending unit 52. The deaeration unit 535 has the same configuration as the inert gas dissolved water generation unit 51, but the addition of the inert gas is not performed.

  A supply pipe 536 is connected to the tank 532, and a stock solution of the removal liquid is supplied from a stock solution supply source (not shown) via the supply pipe 536. A valve 537 is provided in the supply pipe 536, and when the amount of liquid in the tank 532 becomes equal to or less than a predetermined amount, a stock solution of unused removal liquid is supplied (supplemented). Further, a supply pipe 538 provided with a valve 539 is further connected to the tank 532, and an inert gas is supplied from an inert gas supply source (not shown) through the supply pipe 538. In principle, an inert gas is always supplied to the tank 532. Thereby, the inflow of air into the tank 532 can be prevented, and the dissolution of oxygen into the stock solution of the removal liquid stored in the tank 532 is suppressed or prevented. Therefore, it is possible to suppress or prevent an increase in the amount of dissolved oxygen in the stock solution of the removal solution.

  The stock solution of the removal liquid in the tank 532 is pumped out of the tank 532 by the pressure by the inert gas or the suction force by the pump 533, and after being pressurized by the pump 533, the foreign matter is removed through the filter 534. The stock solution of the removal liquid that has passed through the filter 534 is degassed by the degassing unit 535, and the stock solution of the removal liquid in which the amount of dissolved oxygen is reduced is supplied to the preparation unit 52.

  The blending unit 52 is connected to the inert gas dissolved water generation unit 51 via the supply pipe 511 and further connected to the stock solution supply part 53 via the supply pipe 531 as described above. The blending unit 52 includes a mixing unit 521 (manifold) that mixes the stock solution of the removal liquid and the inert gas-dissolved water therein, and the supply pipe 511 and the supply pipe 531 are connected to the mixing unit 521. The supply pipe 511 is provided with a valve 512 and a flow rate adjustment valve 513, and the supply pipe 531 is provided with a valve 522 and a flow rate adjustment valve 523. In the blending unit 52, the removal liquid mixed in a predetermined ratio is generated by adjusting the supply amount of the stock solution of the removal liquid and the supply amount of the inert gas dissolved water to the mixing unit 521. In the present embodiment, hydrogen fluoride (hydrofluoric acid (HF)) is used as a stock solution of the removal liquid, and diluted hydrofluoric acid (DHF) is generated as the removal liquid. In the blending unit 52, buffered hydrofluoric acid (BHF) or the like may be generated. The blending unit 52 supplies the removal liquid to the removal liquid nozzle 43 (see FIG. 2) via the supply pipe 431.

  FIG. 4 is a diagram illustrating the configuration of the supply pipe 431. The supply pipe 431 has a double structure, and has an inner pipe 4311 through which the removal liquid flows and an outer pipe 4312 surrounding the inner pipe 4311. The inner tube 4311 is supported inside the outer tube 4312 by a support member (not shown) interposed between the inner tube 4311 and the outer tube 4312, and the inner tube 4311 and the outer tube 4312 are maintained in a non-contact state. Is done. A cylindrical space is formed between the inner tube 4311 and the outer tube 4312. The inner tube 4311 and the outer tube 4312 are formed of a fluororesin (for example, PFA (polytetrafluoroethylene)) having excellent chemical resistance and heat resistance. Note that PFA transmits oxygen.

  An auxiliary supply pipe 4314 provided with a valve 4313 and an auxiliary exhaust pipe 4316 provided with a valve 4315 are connected to the outer pipe 4312. The auxiliary supply pipe 4314 is connected to an inert gas supply source (not shown), and an inert gas (for example, nitrogen gas) flows into the space between the inner pipe 4311 and the outer pipe 4312 by opening the valves 4313 and 4315. To do. Thereby, air is expelled from the space and the atmosphere in the space is replaced with an inert gas atmosphere. That is, the inner tube 4311 is surrounded by the inert gas. Even after the valves 4313 and 4315 are closed, the state in which the inner tube 4311 is surrounded by the inert gas is maintained, and the amount of oxygen entering the inside of the inner tube 4311 is reduced. Therefore, it is suppressed or prevented that oxygen dissolves in the removal liquid flowing through the inner pipe 4311 and the oxygen concentration in the removal liquid increases. In the present embodiment, the oxygen concentration in the removal liquid discharged from the removal liquid nozzle 43 is 20 ppb or less (for example, 5 to 10 ppb).

  In the substrate processing apparatus 1, the supply pipe 441 that connects the inert gas dissolved water generation unit 51 of FIG. 3 and the rinse liquid nozzle 44 of FIG. 2 has the same structure as the supply pipe 431 and flows in the supply pipe 441. It is suppressed or prevented that oxygen dissolves in the inert gas-dissolved water and the oxygen concentration in the inert gas-dissolved water increases. Note that the supply pipe 431 and the supply pipe 441 do not necessarily have a double structure. However, by using the double structure as described above, the oxygen concentration in the removal liquid and the inert gas-dissolved water flowing in the supply pipe is increased. Can be further suppressed or prevented.

  FIG. 5 is a diagram showing a configuration of the silylation processing unit 6. The silylation processing unit 6 includes a substrate holding table 61 that holds the substrate 9, and the substrate holding table 61 is supported by a support member 62. The substrate holding table 61 has a disk shape with a diameter larger than that of the substrate 9, and the substrate 9 is held in a horizontal state on the substrate holding table 61. A heater 611 is provided inside the substrate holding table 61, and the substrate 9 on the substrate holding table 61 is heated.

  A plurality of (in reality, three or more) through holes 612 and 610 are formed in the substrate holding base 61 and the support member 62. Below each through hole 612 and 610, a vertical direction (vertical) in FIG. Long lift pins 613 are arranged in the direction). The tips of the plurality of lift pins 613 are arranged at the same position in the vertical direction, and are lifted and lowered integrally by the lifting mechanism 614. Specifically, the plurality of lift pins 613 pass through the plurality of through-holes 612 and 610 and the positions of the lift pins 613 above the substrate holding base 61 (hereinafter referred to as “projection positions”), and FIG. The tip is disposed at one of the positions in FIG. 5 (hereinafter referred to as “retracted position”) where the tip is below the plurality of through holes 612 and 610.

  As shown in FIG. 6, the substrate 9 is placed on the plurality of lift pins 613 by the center robot 31 in a state where the plurality of lift pins 613 are arranged at the protruding positions (at this time, a later-described blocking plate 63 is raised. After that, the plurality of lift pins 613 move to the retracted position, whereby the substrate 9 is placed on the substrate holding table 61 as shown in FIG. On the other hand, when the substrate 9 is placed on the substrate holding table 61, the plurality of lift pins 613 move from the retracted position to the protruding position, whereby the substrate 9 is disposed above the substrate holding table 61. As a result, the substrate 9 can be carried out of the silylation processing unit 6 by the center robot 31.

  As shown in FIGS. 5 and 6, the silylation processing unit 6 further includes a blocking plate 63 disposed above the substrate holding table 61. The blocking plate 63 includes a horizontal disc portion 631 and a cylindrical portion 632 that projects downward from the outer edge of the disc portion 631. The diameter of the disc portion 631 is larger than that of the substrate holding base 61, and the annular end surface of the cylindrical portion 632 faces the support member 62. An annular seal member 620 is provided on the support member 62 so as to surround the periphery of the substrate holding table 61. The blocking plate 63 is moved up and down by the lifting mechanism 64, and the position in FIG. 5 where the end surface of the tubular portion 632 contacts the seal member 620 and the end surface of the tubular portion 632 are sufficiently separated from the seal member 620. It is arranged at one of the positions. In the state where the shielding plate 63 is disposed at the position of FIG. 5, the processing space 60 surrounded by the shielding plate 63, the substrate holding base 61 and the support member 62 is sealed, and the shielding plate 63 is moved from the position of FIG. The processing space 60 is released by moving to the position. In the following description, the position of the blocking plate 63 shown in FIG. 5 is referred to as “sealing position”, and the position of the blocking plate 63 illustrated in FIG. 6 is referred to as “open position”.

  Further, an ejection nozzle 65 is provided at the center of the disc portion 631 shown in FIG. 5, and one end of a supply pipe 650 is connected to the ejection nozzle 65. The other end of the supply pipe 650 is branched into a first auxiliary pipe 651 and a second auxiliary pipe 652, and the first auxiliary pipe 651 is connected to a supply source of the silylated material in the vapor (vapor) state, and the second auxiliary pipe 651 is provided. The tube 652 is connected to a nitrogen gas supply source. The first auxiliary pipe 651 and the second auxiliary pipe 652 are provided with valves 653 and 654, respectively. By opening the valve 653 while closing the valve 654, the vapor of the silylated material is ejected from the ejection nozzle 65, and by opening the valve 654 while closing the valve 653, nitrogen gas is ejected from the ejection nozzle 65.

  Silylated materials include TMSI (N-trimethylsilylimidazole), BSTFA (N, O-bis [trimethylsilyl] trifluoroacetamide, N, O-bis (trimethylsilyl) trifluoroacetamide), BSA (N, O-bis). [trimethylsilyl] acetamide, N, O-bis (trimethylsilyl) acetamide), MSTFA (N-methyl-N-trimethylsilyl-trifluoroacetamide, N-methyl-N-trimethylsilyltrifluoroacetamide), TMSDMA (N-trimethylsilyldimethylamine, N-trimethylsilyldimethyl) Amine), TMSDEA (N-trimethylsilyldiethylamine), MTMSA, TMCS (with base) (trimethylchlorosilane), HMDS (Hexamethyldisilazane), and the like in this embodiment. Is used.

  An annular exhaust port 621 is formed on the upper surface of the support member 62 so as to surround the substrate holding base 61 in a plan view. The exhaust port 621 is connected to an exhaust pipe 622, and the exhaust pipe 622 is provided with a pressure adjustment valve 623. As shown in FIG. 5, when gas (a vapor of silylated material or nitrogen gas) is ejected from the ejection nozzle 65 in a state where the blocking plate 63 is disposed at the sealed position, the pressure in the processing space 60 increases. When the pressure in the processing space 60 reaches a predetermined value, the pressure adjustment valve 623 is opened, and the gas in the processing space 60 is exhausted through the exhaust port 621 and the exhaust pipe 622. When the pressure in the processing space 60 becomes less than a predetermined value, the pressure adjustment valve 623 is closed and gas exhaust is stopped. In this way, the processing space 60 is filled with the gas. Thereafter, the ejection of gas from the ejection nozzle 65 is stopped, and the state where the processing space 60 is filled with the gas is maintained.

  Here, the pattern formed on the substrate 9 to be processed in the substrate processing apparatus 1 will be described. FIG. 7 is a diagram showing a pattern formed on the substrate 9. As shown in FIG. 7, a gate electrode 911, a spacer 912, an STI (Shallow Trench Isolation) portion 913, a gate insulating film 914, and the like are formed on the substrate 9, and a number of transistor patterns under manufacturing, that is, A number of patterns for transistors are formed. A silicon oxide film (natural oxide film) 92 exists on the surface of the substrate 9 formed of silicon. Actually, the silicon oxide film is present in the entire region of the substrate 9 where the main surface is exposed. However, in the following description, a region between the spacer 912 and the STI portion 913 (a region to be a source and a drain). In order to pay attention only to this, the silicon oxide film 92 is shown only in the region (the same applies hereinafter). An actual silicon oxide film is a very thin film.

  As will be described later, a silicon germanium film is formed on the substrate 9 having the pattern of FIG. 7, but the processing of the substrate 9 by the substrate processing apparatus 1 in the following description is performed in the flow of the manufacturing process of the semiconductor device. It is performed as a pre-process for forming the silicon germanium film, that is, performed immediately before the formation of the silicon germanium film (it is not necessary to be immediately before in time).

  FIG. 8 is a diagram showing a flow of operations in which the substrate processing apparatus 1 processes the substrate 9. In the substrate processing apparatus 1 of FIG. 1, the substrate 9 in the carrier 90 is taken out by the indexer robot 22 of the indexer block 2 and transferred to the center robot 31 of the processing block 3. Then, the substrate 9 is transported into the oxide film removing unit 4 of FIG. 2 by the center robot 31 and held by the spin chuck 41 (step S11). The chamber body 40 of the oxide film removing unit 4 is provided with an exhaust unit (not shown) and a nitrogen gas introduction unit, and exhausting while introducing nitrogen gas into the chamber body 40, The oxygen concentration is adjusted to 100 ppm or less, for example.

  In the oxide film removing unit 4, the spin chuck 41 starts rotating by the spin motor 411 and the removal liquid nozzle 43 is arranged at the supply position. When the spin chuck 41 reaches a predetermined rotational speed, the removal liquid is applied to the main surface of the substrate 9 from the removal liquid nozzle 43 by opening the valve 432 of the supply pipe 431 (step S12). At this time, the removal liquid nozzle 43 swings in a direction along the main surface of the substrate 9 as necessary (the same applies to the application of the rinse liquid from the rinse liquid nozzle 44 described later). When the application of the removal liquid is continued for a predetermined time, the discharge of the removal liquid from the removal liquid nozzle 43 is stopped, and the removal liquid nozzle 43 is returned to the standby position.

  Subsequently, the rinsing liquid nozzle 44 is arranged at the supply position, and the rinsing liquid (inert gas dissolved water) is applied from the rinsing liquid nozzle 44 to the main surface of the substrate 9 by opening the valve 442 of the supply pipe 441. The removal liquid or the like adhering to the main surface is removed by the rinse liquid (step S13). When the application of the rinse liquid is continued for a predetermined time, the discharge of the rinse liquid from the rinse liquid nozzle 44 is stopped, and the rinse liquid nozzle 44 is returned to the standby position. Further, the rotation speed of the spin chuck 41 is increased, and the substrate 9 is dried. When the drying of the substrate 9 is continued for a predetermined time, the rotation of the spin chuck 41 is stopped, and the substrate 9 is taken out from the oxide film removing unit 4 by the center robot 31. By the processing in steps S12 and S13, the silicon oxide film 92 (see FIG. 7) on the substrate 9 is removed as shown in FIG. Note that, after the rinsing liquid is applied in step S13, before the substrate 9 is dried, a mixed liquid (SC1) of ammonia and hydrogen peroxide solution is applied onto the substrate 9 from a nozzle separately provided in the oxide film removing unit 4. May be. In this case, after the application of SC1, the rinsing liquid is applied again, and then the substrate 9 is dried.

  In the removal liquid and the rinsing liquid in the substrate processing apparatus 1, the oxygen concentration is reduced by the processing liquid supply unit 5 in FIG. 3, and the surface of the substrate 9 is in a state in which many Si—F groups and Si—H groups exist. Become. On the other hand, Si—OH groups are also present on the surface of the substrate 9 due to a slight amount of oxygen dissolved in the removal liquid and the rinse liquid and oxygen in the surrounding atmosphere.

  Subsequently, the substrate 9 is transferred into the silylation processing unit 6 by the center robot 31 (step S14). At this time, as shown in FIG. 6, the blocking plate 63 is disposed in the open position, and the substrate 9 is placed on the plurality of lift pins 613 disposed in the protruding position. Then, after the center robot 31 retreats out of the silylation processing unit 6, the plurality of lift pins 613 move to the retreat position, whereby the substrate 9 is placed on the substrate holding table 61. Further, the blocking plate 63 moves to the sealed position, and the substrate 9 is placed in the sealed processing space 60 as shown in FIG.

  In the silylation processing unit 6, the nitrogen gas is started to be ejected from the ejection nozzle 65 by opening the valve 654, and the pressure regulating valve 623 is opened and closed according to the pressure in the processing space 60. As a result, the air in the processing space 60 is replaced with nitrogen gas, and the processing space 60 is filled with nitrogen gas. After the ejection of nitrogen gas from the ejection nozzle 65 is stopped, the valve 653 is opened, and the ejection of the vapor of silylated material from the ejection nozzle 65 is started. Further, the pressure adjustment valve 623 is opened and closed according to the pressure in the processing space 60. Thereby, the nitrogen gas in the processing space 60 is replaced with the vapor of the silylated material, and the processing space 60 is filled with the vapor of the silylated material. After a predetermined time has elapsed after the start of the ejection of the silylated material vapor, the valve 653 is closed to stop the ejection of the silylated material vapor from the ejection nozzle 65.

  In this manner, the substrate 9 is filled with the vapor of the silylated material, and the substrate 9 is held in the vapor atmosphere of the silylated material for a predetermined time. Thereby, a silylation process is performed on the main surface of the substrate 9, and the main surface is silylated as shown in FIG. 10 (step S15). In FIG. 10, a portion 93 silylated by adding parallel oblique lines in the vicinity of the main surface of the substrate 9 is abstractly shown. At this time, since the substrate 9 on the substrate holder 61 in FIG. 5 is heated to a constant temperature higher than room temperature by the heater 611, silylation of the main surface is promoted.

  When the substrate 9 is held in the vapor atmosphere of the silylated material for a predetermined time, the ejection of nitrogen gas from the ejection nozzle 65 is started. As a result, the vapor of the silylated material in the processing space 60 and the gas generated by the silylation are replaced with nitrogen gas, and the processing space 60 is filled with nitrogen gas.

  When the processing space 60 is filled with nitrogen gas, the blocking plate 63 is disposed at the open position, the processing space 60 is opened, and the plurality of lift pins 613 move to the protruding position. The substrates 9 on the plurality of lift pins 613 are carried out of the silylation processing unit 6 by the center robot 31 of FIG. 1 and delivered to the indexer robot 22 of the indexer block 2. Then, the indexer robot 22 returns the carrier 90 (step S16). Actually, the processes in steps S11 to S16 are partially performed on the plurality of substrates 9 in parallel.

  The processed substrate 9 in the substrate processing apparatus 1 is transported to another apparatus, and a process related to formation of a silicon germanium film is performed. In the process relating to the formation of the silicon germanium film, the substrate 9 is pre-baked before the silicon germanium film is actually formed. In the present embodiment, in the pre-baking, for example, the substrate 9 is heated at 700 ° C. for 10 to 30 minutes.

Here, the chemical bond energy of the substance on the substrate 9 will be described. In the silylation treatment in the substrate processing apparatus 1, when HMDS is used as the silylation material, the surface of the substrate 9 after the silylation treatment is in a state where a large number of silyl groups due to HMDS are present. As shown in FIG. 11, since the bond energy in the silyl group caused by HMDS is smaller than the bond energy of Si—O in SiO ₂ and the bond energy of Si—F in SiF ₄ , at a relatively low temperature in prebaking. The silyl group on the main surface of the substrate 9 can be removed.

  When the pre-baking of the substrate 9 is completed, a silicon germanium film 94 is formed on the main surface as shown in FIG. Formation of the silicon germanium film 94 can cause distortion in the silicon layer of the channel portion. A transistor in which the silicon layer in the channel portion is distorted can operate at high speed. The silicon germanium film is formed by, for example, a thermal CVD method.

  FIG. 13 is a diagram showing a change (growth) in the thickness of the natural oxide film after the removal of the silicon oxide film on the substrate 9. Indicates the elapsed time after removal. In FIG. 13, the removal of the silicon oxide film and the silylation treatment (hereinafter referred to as “low oxygen treatment + silylation treatment”) using the treatment liquid (removal liquid and rinse liquid) whose oxygen concentration has been reduced by the treatment liquid supply unit 5. .) Is indicated by a line denoted by reference numeral L1, and only the removal of the silicon oxide film by the treatment liquid having a reduced oxygen concentration (hereinafter referred to as “low oxygen treatment”). The change in the thickness of the oxide film on the substrate on which the silicon oxide film is formed is indicated by a line denoted by L2, and the removal of the silicon oxide film by the processing liquid whose oxygen concentration is not reduced (hereinafter referred to as “standard process”). The change in the thickness of the oxide film on the substrate on which only the process is performed is indicated by a line labeled L3. In the “low oxygen treatment” and “standard treatment”, the silylation treatment is not performed.

  From FIG. 13, the thickness of the oxide film is smaller in the substrate subjected to the “low oxygen treatment” than the substrate subjected to the “standard treatment”, and the silylation treatment is performed in addition to the “low oxygen treatment”. It can be seen that the thickness of the oxide film is further reduced in the substrate that has been performed (that is, “low oxygen treatment + silylation treatment” has been performed). In the substrate subjected to “low oxygen treatment + silylation treatment”, for example, the thickness of the oxide film after being left for 48 hours is smaller than the thickness of the oxide film on the substrate immediately after the standard treatment, It is also possible to set the Q time to 48 hours.

  FIG. 14 is a diagram showing the oxygen concentration in the silicon germanium film formed on the substrate 9. FIG. 14 shows that the oxygen concentration in the silicon germanium film is lower in the substrate subjected to the “low oxygen treatment” than the substrate subjected to the “standard treatment”, and silylation is performed in addition to the “low oxygen treatment”. It can be seen that the oxygen concentration in the silicon germanium film is further reduced in the processed substrate. Therefore, it can be said that an appropriate silicon germanium film can be formed by “low oxygen treatment + silylation treatment”.

  As described above, in the substrate processing apparatus 1 of FIG. 1, after the silicon oxide film on one main surface of the substrate 9 is removed by the oxide film removing unit 4, silylation is performed by the silylation processing unit 6. The material is added and the main surface is subjected to silylation treatment. Thereby, after removing the silicon oxide film, the Q time until the formation of the silicon germanium film can be lengthened, and the pre-baking temperature in the formation of the silicon germanium film can be lowered.

  Further, in the oxide film removing unit 4 of FIG. 2, the removing liquid nozzle 43 applies a removing liquid to the main surface of the substrate 9 as a removing liquid applying part, and the rinsing liquid nozzle 44 serves as a rinsing liquid applying part on the main surface. Is granted. Then, the treatment liquid supply unit 5 serves as an oxygen concentration reduction unit to reduce the oxygen concentration of the removal liquid and the rinsing liquid, thereby extending the Q time after the removal of the silicon oxide film until the formation of the silicon germanium film, The pre-baking temperature in the formation of the silicon germanium film can be further lowered.

  FIG. 15 is a diagram illustrating another example of the silylation processing unit. 15 includes a chamber main body 61a, a shutter 62a for opening / closing a loading / unloading port 611a formed on a side surface of the chamber main body 61a, and a mounting plate 63a disposed at a lower portion in the chamber main body 61a. . The upper space in the chamber body 61a is a supply unit 64a that supplies gas toward the substrate 9 as will be described later, and the space between the space in which the mounting plate 63a is arranged in the chamber body 61a and the supply unit 64a. And partitioned by a diffusion plate 641a.

  A jet nozzle 65a is provided in a portion of the chamber body 61a above the supply unit 64a, and one end of a supply pipe 651a is connected to the jet nozzle 65a. The other end of the supply pipe 651a is connected to the first auxiliary pipe 653a and the second auxiliary pipe 654a via a three-way valve 652a. The first auxiliary pipe 653a is connected to a supply source of the silylated material, and the second auxiliary pipe 654a is connected to a supply source of nitrogen gas. Supply of the silylated material to the ejection nozzle 65a is controlled by a valve 655a, and supply of nitrogen gas is controlled by a valve 656a.

  The mounting plate 63a has a plurality of lift pins 631a in the same manner as the substrate holding table 61 of FIG. A heater 632a is provided in the mounting plate 63a. In FIG. 15, a first exhaust port 612a is provided on the left side (loading outlet 611a side) of the mounting plate 63a, and a second exhaust port 613a is provided on the right side. An exhaust pump (not shown) is connected to the first exhaust port 612a and the second exhaust port 613a.

  An auxiliary supply unit 66a is provided at a position facing the loading / unloading port 611a in the chamber body 61a. A space in which the placement plate 63a is disposed in the chamber body 61a and the auxiliary supply unit 66a are partitioned by a filter 661a. The auxiliary supply part 66a is provided with a supply port 662a, and one end of a supply pipe 663a is connected to the supply port 662a. The supply pipe 663a is provided with a valve 664a, and the other end of the supply pipe 663a is connected to a supply source of nitrogen gas.

  When the silylation process is performed in the silylation processing unit 6a, the loading / unloading port 611a of the chamber body 61a is opened by moving the shutter 62a in the direction indicated by the arrow A1 in FIG. At this time, exhausting from the first exhaust port 612a while opening the valve 664a prevents outside air from entering the chamber body 61a from the opened loading / unloading port 611a. Subsequently, similarly to the silylation processing unit 6 in FIG. 6, the substrate 9 is placed on the lift pins 631 a protruding upward from the placement plate 63 a by the center robot 31. After the center robot 31 has retreated from the inside of the chamber body 61a, the loading / unloading port 611a is closed by moving the shutter 62a. Then, the lift pins 631a are lowered to place the substrate 9 on the placement plate 63a.

  Subsequently, the valve 664a is closed and the three-way valve 652a is switched to the valve 656a side, and then the valve 656a is opened. Further, exhaust is performed at the first exhaust port 612a and the second exhaust port 613a. Thereby, the inside of the chamber body 61a is purged with nitrogen gas, and the pressure is reduced to a pressure lower than the atmospheric pressure (for example, 20 [kPa (kilopascal)]). Thereafter, the valve 656a is closed and the three-way valve 652a is switched to the valve 655a side, and then the valve 655a is opened. Thereby, the silylated material is ejected from the ejection nozzle 65a, and the silylated material is supplied toward the substrate 9 from the supply unit 64a. At this time, the exhaust amount from the first exhaust port 612a and the second exhaust port 613a is lowered. Preferably, the substrate 9 is heated by a heater 632a built in the mounting plate 63a. The heating temperature is, for example, about 100 to 120 ° C.

  After the above-described state is maintained for a predetermined time, the plurality of lift pins 631a are raised and the substrate 9 is disposed above the placement plate 63a. Further, after closing the valve 655a and switching the three-way valve 652a to the valve 656a side, the valve 656a is opened, whereby nitrogen gas is supplied to the substrate 9.

  Subsequently, the exhaust amount from the first exhaust port 612a and the second exhaust port 613a is increased, and the state in which the pressure in the chamber body 61a is reduced is maintained for a certain time. Thereafter, the exhaust amount from the first exhaust port 612a and the second exhaust port 613a is lowered, and the pressure in the chamber body 61a is returned to atmospheric pressure. Then, the loading / unloading port 611a of the chamber body 61a is opened, and the substrate 9 is taken out from the silylation processing unit 6a by the center robot 31.

  As described above, also in the silylation processing unit 6a of FIG. 15, the silicon oxide film on one main surface of the substrate 9 is removed by the oxide film removal unit 4 as in the silylation processing unit 6 of FIG. Immediately thereafter, the silylation process is performed on the substrate 9. As a result, the Q time until the formation of the silicon germanium film can be increased, and the pre-baking temperature in the formation of the silicon germanium film can be lowered.

  FIG. 16 is a diagram showing a configuration of a substrate processing apparatus 1a according to the second embodiment of the present invention. In the substrate processing apparatus 1a of FIG. 16, the configuration of the processing block 3a is different from that of the substrate processing apparatus 1 of FIG. Other configurations are the same as those in FIG. 1, and are denoted by the same reference numerals. In the processing block 3a of FIG. 16, four processing units 7 are provided, and the four processing units 7 have the same configuration.

  FIG. 17 is a diagram showing the configuration of one processing unit 7. The processing unit 7 includes a spin chuck 71 that holds the substrate 9, a removal liquid nozzle 72 that is a removal liquid application unit that applies a removal liquid to the main surface of the substrate 9, and a rinsing liquid application that applies a rinsing liquid to the main surface of the substrate 9. A rinsing liquid nozzle 73 that is a part and a chamber body 70 that houses the components of the processing unit 7 are provided. The spin chuck 71 is rotated around an axis parallel to the vertical direction by a spin motor 711. Further, the removal liquid nozzle 72 and the rinsing liquid nozzle 73 are the same as the removal liquid nozzle 43 and the rinsing liquid nozzle 44 in the oxide film removal section 4 of FIG. 5 is connected.

  The processing unit 7 further includes a blocking plate 74 disposed above the spin chuck 71 in the chamber body 70, a clean air supply unit 700 that supplies clean air from the upper part of the chamber body 70 into the chamber body 70, and a chamber An exhaust unit (not shown) that exhausts the atmosphere in the chamber body 70 from the lower part of the body 70 is provided. The clean air supply unit 700 and the exhaust unit are always driven, and an airflow flowing from the upper side to the lower side is formed in the chamber body 70.

  The blocking plate 74 includes a horizontal disc portion 741, a cylindrical portion 742 that protrudes downward from the outer edge of the disc portion 741, and a heater 743 connected to the disc portion 741. A support shaft 744 is connected to the center of the upper surface of the disc portion 741. A through hole penetrating in the vertical direction is formed in the disc portion 741 and the support shaft 744, and the through hole opens at the center of the lower surface of the disc portion 741. The introduction pipe 75 is inserted into the through hole in a non-contact state with the inner surface of the through hole, and the lower end of the introduction pipe 75 is located at the opening of the through hole in the disc portion 741.

  As shown in FIG. 18, a first jet port 751 and a second jet port 752 are formed at the lower end of the introduction pipe 75. One end of the first supply pipe 753 shown in FIG. 17 is connected to the flow path that continues to the first jet outlet 751 in the introduction pipe 75, and the other end of the first supply pipe 753 is connected to the supply source of the silylated material. The In this embodiment, a vapor silylated material is used, but a liquid silylated material may be used. In addition, one end of the second supply pipe 754 is connected to a flow path that is continuous with the second jet outlet 752 in the introduction pipe 75, and the other end of the second supply pipe 754 is connected to a supply source of nitrogen gas. The first supply pipe 753 and the second supply pipe 754 are provided with valves 755 and 756, respectively.

  Further, a cylindrical gas supply path 745 is formed between the support shaft 744 (the inner surface of the through hole) and the introduction pipe 75, and a gas supply is provided on the lower surface of the disc portion 741 as shown in FIG. An annular spout 746 in the path 745 is formed. As shown in FIG. 17, one end of a gas supply pipe 747 is connected to the gas supply path 745, and the other end of the gas supply pipe 747 is connected to a nitrogen gas supply source. A valve 748 is provided in the gas supply pipe 747.

  The support shaft 744 is connected to an elevating mechanism 76, and the elevating mechanism 76 moves the blocking plate 74 up and down together with the support shaft 744. Specifically, the blocking plate 74 is a position where the disc portion 741 is close to the substrate 9 on the spin chuck 71 (a position indicated by a two-dot chain line in FIG. 17, hereinafter referred to as “proximity position”). ), And the disk portion 741 is disposed at one of the positions where the disk portion 741 is largely separated from the spin chuck 71 (the position indicated by the solid line in FIG. 17 and hereinafter referred to as “retracted position”). In a state where the blocking plate 74 is disposed at the close position, the lower surface of the disc portion 741 is close to the upper surface of the substrate 9, and the cylindrical tubular portion 742 surrounds the periphery of the outer edge of the substrate 9. When the blocking plate 74 is disposed in the proximity position, the removal liquid nozzle 72 and the rinsing liquid nozzle 73 are moved to a position where they do not interfere with the blocking plate 74 by a moving mechanism (not shown).

  When the substrate processing apparatus 1a in FIG. 16 processes the substrate 9, the substrate 9 in the carrier 90 is taken out by the indexer robot 22 of the indexer block 2 as in the substrate processing apparatus 1 in FIG. It is delivered to the center robot 31. Subsequently, the shutter 701 provided in the chamber body 70 of the processing unit 7 in FIG. 17 is opened by the opening / closing mechanism 702. Then, the substrate 9 is transported into the processing unit 7 by the center robot 31 and held by the spin chuck 71 (FIG. 8: Step S11). At this time, the blocking plate 74 is disposed at the retracted position.

  After the center robot 31 moves to the outside of the processing unit 7, the shutter 701 is closed and the spin motor 711 starts to rotate the spin chuck 71. Further, the removal liquid nozzle 72 is disposed at a predetermined supply position, and the valve 722 provided in the supply pipe 721 is opened, whereby the removal liquid is applied from the removal liquid nozzle 72 to the center on the main surface of the substrate 9. (Step S12). By the rotation of the substrate 9, the removal liquid spreads outward along the main surface, and the removal liquid is applied to the entire main surface of the substrate 9 (the same applies to the application of a rinsing liquid described later and the application of the silylated material). ). When the application of the removal liquid is continued for a predetermined time, the discharge of the removal liquid from the removal liquid nozzle 72 is stopped by closing the valve 722, and then the removal liquid nozzle 72 is returned to the predetermined standby position.

  Subsequently, the rinsing liquid nozzle 73 is disposed at a predetermined supply position, and the valve 732 provided in the supply pipe 731 is opened, so that the rinsing liquid (inert gas) is transferred from the rinsing liquid nozzle 73 onto the main surface of the substrate 9. Dissolved water) is applied, and the removal liquid adhering to the main surface is removed by the rinse liquid (step S13). When the application of the rinsing liquid is continued for a predetermined time, the discharge of the rinsing liquid from the rinsing liquid nozzle 73 is stopped by closing the valve 732, and then the rinsing liquid nozzle 73 is returned to the standby position. Further, the rotation speed of the spin chuck 71 is increased, and the substrate 9 is dried. When the drying of the substrate 9 is continued for a predetermined time, the rotation of the spin chuck 71 is reduced to a predetermined rotation number, and the drying of the substrate 9 is completed. Subsequently, the blocking plate 74 moves from the retracted position to the close position. In the substrate processing apparatus 1a, the process of step S14 in FIG. 8 is omitted.

  In the processing unit 7, by opening the valve 756 of the second supply pipe 754 and the valve 748 of the gas supply pipe 747, nitrogen gas is jetted from the second jet outlet 752 and the annular jet outlet 746 (see FIG. 18). Thereby, the atmosphere of the space surrounded by the blocking plate 74 and the spin chuck 71 is replaced with nitrogen gas. The gas flowing out from between the cylindrical portion 742 and the outer edge of the spin chuck 71 is exhausted from the chamber body 70 through the exhaust port 703 provided in the chamber body 70.

  Subsequently, after the valves 756 and 748 are closed, the valve 755 is opened, whereby the silylated material is ejected from the first ejection port 751 (see FIG. 18). The ejection of the silylated material is continued for a predetermined time. In this manner, the main surface of the substrate 9 is subjected to silylation treatment, and the main surface is silylated (step S15). At this time, the substrate 9 may be indirectly heated by the heater 743 connected to the disc portion 741.

  When the valve 755 is closed and ejection of the silylated material is completed, the valves 756 and 748 are opened, and nitrogen gas is ejected from the second ejection port 752 and the annular ejection port 746. The ejection of nitrogen gas is continued for a predetermined time, whereby the atmosphere in the space surrounded by the shielding plate 74 and the spin chuck 71 is replaced with nitrogen gas.

  When the valves 756 and 748 are closed and the ejection of the nitrogen gas is completed, the rotation of the substrate 9 is stopped and the blocking plate 74 moves to the retracted position. Note that after purging with nitrogen gas, the substrate 9 may be dried by high-speed rotation of the substrate 9 as necessary. Thereafter, the shutter 701 is opened, and the substrate 9 is taken out of the processing unit 7 by the center robot 31 of FIG. 16 and delivered to the indexer robot 22 of the indexer block 2. Then, the indexer robot 22 returns the carrier 90 (step S16). Note that, after the rinsing liquid is applied in step S13, before the substrate 9 is dried, a mixed liquid (SC1) of ammonia and hydrogen peroxide may be applied onto the substrate 9 from a nozzle provided separately. In this case, after the application of SC1, the rinsing liquid is applied again, and then the substrate 9 is dried.

  As described above, in the processing unit 7 of the substrate processing apparatus 1a, an oxide film removing unit that removes the silicon oxide film is realized by the configuration including the removing liquid nozzle 72, the rinsing liquid nozzle 73, and the processing liquid supply unit 5, A silylation processing unit for performing a silylation process is realized by the configuration including the blocking plate 74 and the introduction pipe 75, and the spin chuck 71 which is a holding unit for holding the substrate 9 is shared in the oxide film removal unit and the silylation processing unit. The Therefore, after the silicon oxide film on one main surface of the substrate 9 is removed, the silylation material is applied to the main surface without moving the substrate 9, and the silylation process is performed. Thereby, the time from the removal of the silicon oxide film to the silylation process can be shortened, and the growth of the natural oxide film from the removal of the silicon oxide film to the silylation process can be suppressed. As a result, the Q time until the formation of the silicon germanium film can be increased, and the prebaking temperature in the formation of the silicon germanium film can be lowered.

  In the processing unit 7 of FIG. 17, the case where the cylindrical portion 742 of the blocking plate 74 is cylindrical has been described. For example, as shown in FIG. 19, the cylindrical portion 742 is separated downward from the disc portion 741. According to the above, the shape may increase in diameter. In addition, in the cylindrical portion 742 in FIG. 19, the thickness decreases as the distance from the disc portion 741 decreases, but a cylindrical portion 742 that increases in thickness as the distance from the disc portion 741 increases. .

  FIG. 20 is a diagram showing a configuration of a substrate processing apparatus 1b according to the third embodiment of the present invention. In the substrate processing apparatus 1b of FIG. 20, the configuration of the processing block 3b is different from that of the substrate processing apparatus 1 of FIG. Other configurations are the same as those in FIG. 1, and are denoted by the same reference numerals. In the processing block 3b of FIG. 20, two steam processing units 8, one rinsing unit 4a, and one silylation processing unit 6 are provided. The rinsing unit 4 a is obtained by omitting the removing liquid nozzle 43 in the oxide film removing unit 4 of FIG. 2, and only the processing with the rinsing liquid from the rinsing liquid nozzle 44 is performed. The silylation processing unit 6 is the same as the silylation processing unit 6 of FIG.

  FIG. 21 is a diagram illustrating a configuration of the steam processing unit 8. The steam processing unit 8 includes a hot plate 81 having a heater therein, and the substrate 9 is held on the upper surface of the hot plate 81 by suction adsorption. The hot plate 81 is rotated around an axis parallel to the vertical direction by a motor 811. A steam ejection part 82 is provided above the hot plate 81. In the vapor ejection portion 82, hydrofluoric acid vapor, which will be described later, is ejected toward the substrate 9 on the hot plate 81 through the diffusion plate 820.

  One end of a supply pipe 821 is connected to the vapor ejection part 82, and the other end of the supply pipe 821 is connected to a hydrofluoric acid tank 83 that stores hydrofluoric acid (or other removal liquid may be used). A valve 822 is provided in the supply pipe 821. Hydrofluoric acid is appropriately supplied from a hydrofluoric acid supply source (not shown) into the hydrofluoric acid tank 83, and a predetermined amount of hydrofluoric acid is always stored in the hydrofluoric acid tank 83. The hydrofluoric acid tank 83 is provided with a supply pipe 831 connected to a nitrogen gas supply source (not shown), and nitrogen gas is supplied from the nitrogen gas supply source into the hydrofluoric acid tank 83 through the supply pipe 831. Then, by opening the valve 822 of the supply pipe 821, hydrofluoric acid vapor is supplied to the vapor ejection part 82 through the supply pipe 821 together with the nitrogen gas.

  A gas supply unit 84 including a configuration surrounded by a broken line in FIG. 21 is adjusted to a predetermined temperature by a temperature controller and a heating unit (not shown), and is supplied from the vapor ejection unit 82 toward the main surface of the substrate 9. Of steam is maintained at a predetermined temperature. 21, the temperature of the substrate 9 is adjusted to 12 ° C. to 120 ° C., preferably 30 ° C. to 100 ° C. Actually, the steam ejection part 82, the hot plate 81, and the motor 811 are accommodated in a chamber body (not shown).

  When the substrate processing apparatus 1b of FIG. 20 processes the substrate 9, the substrate 9 is transferred into the chamber body of the vapor processing unit 8 and placed on the hot plate 81 of FIG. 21 (FIG. 8: step). S11). Subsequently, nitrogen gas is supplied from a nozzle provided in the chamber body and the inside of the chamber body is decompressed, and the atmosphere in the chamber body is replaced with nitrogen gas.

  When the inside of the chamber body is filled with nitrogen gas, the substrate 9 is rotated at a predetermined rotational speed (for example, 10 to 300 rpm, here 150 rpm). Further, by opening the valve 822, hydrofluoric acid vapor is ejected from the vapor ejection portion 82 toward the substrate 9 at a predetermined flow rate (for example, 5 to 100 liters per minute, here 30 liters per minute). Is done. The ejection of hydrofluoric acid vapor is continued for a predetermined time, and the silicon oxide film on the substrate 9 is removed (step S12). Thereafter, the valve 822 is closed, and the ejection of hydrofluoric acid vapor from the vapor ejection portion 82 is stopped. Then, nitrogen gas is supplied into the chamber body, and the atmosphere in the chamber body is replaced with nitrogen gas.

  Subsequently, the substrate 9 is taken out from the vapor processing unit 8 and transferred to the rinsing unit 4a. Then, similarly to the first embodiment, a rinsing liquid is applied on the substrate 9 from the rinsing liquid nozzle 44 (see FIG. 2), and a rinsing process is performed (step S13). When the rinsing process is completed, the substrate 9 is transferred into the silylation processing unit 6 (step S14), and the main surface of the substrate 9 is subjected to the silylation process (step S15). When the silylation process is completed, the substrate 9 is taken out from the silylation processing unit 6 and returned into the carrier 90 (step S16).

  As described above, in the substrate processing apparatus 1b, after the silicon oxide film on one main surface of the substrate 9 is removed by the vapor of hydrofluoric acid in the vapor processing unit 8 which is an oxide film removing unit, silylation is performed. In the processing unit 6, a silylation material is applied to the main surface, and a silylation process is performed. As a result, the Q time until the formation of the silicon germanium film can be increased, and the pre-baking temperature in the formation of the silicon germanium film can be lowered.

  FIG. 22 is a diagram showing a configuration of a substrate processing apparatus 1c according to the fourth embodiment of the present invention. In the substrate processing apparatus 1c of FIG. 22, the configuration of the processing block 3c is different from that of the substrate processing apparatus 1 of FIG. Other configurations are the same as those in FIG. 1, and are denoted by the same reference numerals. In the processing block 3c of FIG. 22, two steam processing units 8a and two rinsing units 4a are provided.

  FIG. 23 is a diagram illustrating a configuration of the steam processing unit 8a. The steam processing unit 8a is different from the steam processing unit 8 of FIG. 21 in the configuration of the gas supply unit 84a. Other configurations are the same as those in FIG. 21, and are denoted by the same reference numerals.

  In the gas supply part 84a, one end of another supply pipe 851 is connected between the vapor ejection part 82 and the valve 822 in the supply pipe 821, and the other end of the supply pipe 851 stores a silylated material for storing a liquid silylated material. Connected to the tank 85. The supply pipe 851 is provided with a valve 852. A silylated material is appropriately supplied into the silylated material tank 85 from a supply source of a silylated material (not shown), and a predetermined amount of the silylated material is always stored in the silylated material tank 85. The silylated material tank 85 is provided with a supply pipe 832 connected to a nitrogen gas supply source (not shown), and nitrogen gas is supplied from the nitrogen gas supply source into the silylated material tank 85 through the supply pipe 832. Then, by opening the valve 852 of the supply pipe 851, the vapor of the silylated material is supplied to the vapor ejection part 82 through the supply pipe 851 and a part of the supply pipe 821 together with the nitrogen gas.

  When the substrate processing apparatus 1c in FIG. 22 processes the substrate 9, the substrate 9 is transferred into the chamber body of the vapor processing unit 8a and placed on the hot plate 81 in FIG. 23 (FIG. 8: step). S11). In addition, before the board | substrate 9 is conveyed in the vapor processing part 8a, pre-rinsing may be performed with respect to the board | substrate 9 in the rinse part 4a as needed. Subsequently, nitrogen gas is supplied from a nozzle provided in the chamber body and the inside of the chamber body is decompressed, and the atmosphere in the chamber body is replaced with nitrogen gas.

  When the inside of the chamber body is filled with nitrogen gas, the substrate 9 is rotated at a predetermined rotational speed and the hydrofluoric acid vapor is supplied from the vapor ejection portion 82 to the substrate 9 as in the third embodiment. Erupted toward the. In the vapor processing unit 8a, the ejection of hydrofluoric acid vapor is continued for a predetermined time, and the silicon oxide film on the substrate 9 is removed (step S12). When the ejection of hydrofluoric acid vapor is stopped, nitrogen gas is supplied into the chamber body, and the atmosphere in the chamber body is replaced with nitrogen gas.

  Subsequently, by opening the valve 852, the vapor (including nitrogen gas) of the silylated material at a predetermined flow rate (for example, 5 to 100 liters per minute, in this case, 30 liters per minute) from the steam ejection part 82. .) Is ejected toward the substrate 9. Thereby, a silylation process is performed with respect to the main surface of the board | substrate 9 (step S15). When the ejection of the silylated material vapor continues for a predetermined time, the valve 852 is closed and the ejection of the silylated material vapor is stopped. Then, nitrogen gas is supplied into the chamber body, and the atmosphere in the chamber body is replaced with nitrogen gas. Thereafter, the substrate 9 is taken out from the vapor processing unit 8a and returned into the carrier 90 (step S16). In the substrate processing apparatus 1c, steps S13 and S14 in FIG. 8 are omitted. Further, the process of replacing the atmosphere in the chamber body with nitrogen gas may be omitted between step S12 and step S15.

  As described above, in the vapor processing unit 8a of the substrate processing apparatus 1c, an oxide film removing unit that removes the silicon oxide film is realized by the configuration including the hydrofluoric acid tank 83, and the silylation material tank 85 is included in the silylation material tank 85. A silylation processing unit that performs crystallization processing is realized, and the oxide film removal unit and the silylation processing unit share a hot plate 81 that is a holding unit that holds the substrate 9. Therefore, after the silicon oxide film on one main surface of the substrate 9 is removed by the vapor processing unit 8a, the silylation material vapor is applied to the main surface without moving the substrate 9, Processing is performed. Thereby, the time from the removal of the silicon oxide film to the silylation process can be shortened, and the growth of the natural oxide film from the removal of the silicon oxide film to the silylation process can be suppressed. As a result, the Q time until the formation of the silicon germanium film can be increased, and the prebaking temperature in the formation of the silicon germanium film can be lowered.

  Further, in the steam processing unit 8a, the number of parts in the substrate processing apparatus 1c is reduced by sharing the steam ejection unit 82 that ejects steam toward the substrate 9 in the oxide film removing unit and the silylation processing unit. Can do.

  FIG. 24 is a diagram showing a configuration of a substrate processing apparatus 1d according to the fifth embodiment of the present invention. In the substrate processing apparatus 1d of FIG. 24, the configuration of the processing block 3d is different from that of the substrate processing apparatus 1 of FIG. Other configurations are the same as those in FIG. 1, and are denoted by the same reference numerals. In the processing block 3d of FIG. 24, four steam processing units 8b are provided. The steam processing unit 8b is provided with a rinsing liquid nozzle for rinsing processing in the steam processing unit 8a of FIG. 23, and is capable of rinsing. Accordingly, in the substrate processing apparatus 1d of FIG. 24, the removal of the silicon oxide film by the hydrofluoric acid vapor, the rinsing treatment by the rinsing liquid, and the silylation treatment by the vapor of the silylating material can be performed without moving the substrate 9. Can be done continuously.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made.

  In the first and second embodiments, the treatment liquid supply unit 5 reduces the oxygen concentration of both the removal liquid and the rinsing liquid, but even if the oxygen concentration in only one of the removal liquid and the rinsing liquid is reduced. Good. In the treatment liquid supply unit 5, the oxygen concentration in at least one of the removal liquid and the rinsing liquid is reduced, so that the Q time until the formation of the silicon germanium film is further increased in combination with the silylation treatment after the removal of the silicon oxide film. At the same time, the pre-baking temperature in forming the silicon germanium film can be further lowered.

  In the first and third embodiments, the center robot 31 transports the substrate 9 from which the silicon oxide film has been removed from the oxide film removing unit to the silylation processing unit 6, thereby contaminating the surface of the substrate 9. However, the substrate moving mechanism that moves the substrate 9 from the oxide film removing unit to the silylation processing unit 6 may be realized by a mechanism other than the center robot 31.

  Arrangement of constituent elements (oxide film removal unit 4, silylation processing units 6, 6a, processing unit 7, vapor processing units 8, 8a, 8b) in processing blocks 3, 3a-3d in substrate processing apparatuses 1, 1a-1d May be appropriately changed. For example, a plurality of components may be stacked in the vertical direction.

  After removing the silicon oxide film, a silylation process is performed to increase the Q time until the formation of the silicon germanium film and lower the prebaking temperature. It may be employed in a type of substrate processing apparatus. Further, the substrate 9 to be processed in the substrate processing apparatuses 1 and 1a to 1d may be formed with a pattern other than the transistor pattern.

  The configurations in the above-described embodiments and modifications may be combined as appropriate as long as they do not contradict each other.

DESCRIPTION OF SYMBOLS 1,1a-1d Substrate processing apparatus 4 Oxide film removal part 5 Processing liquid supply part 6, 6a Silylation processing part 7 Processing unit 8, 8a, 8b Steam processing part 9 Substrate 31 Center robot 43, 72 Removal liquid nozzle 44, 73 Rinsing liquid nozzle 71 Spin chuck 81 Hot plate S12, S13, S15 Step

Claims (5)

As a pre-process for forming a silicon germanium film on a silicon substrate, a substrate processing method for processing the silicon substrate,
a) removing a silicon oxide film on one main surface of the silicon substrate;
b) The step performed after the step a), in which the silicon oxide film is removed by the step a) by applying a silylation material to the main surface to give a silylation treatment. A step of bringing the surface into a state in which the growth of the natural oxide film is suppressed;
Equipped with a,
Step a)
a1) applying a removing liquid for removing the silicon oxide film to the main surface;
a2) applying a rinsing liquid to the main surface;
With
Substrate processing method wherein b) step, characterized in Rukoto performed following the a2) step. The substrate processing method according to claim 1 ,
The substrate processing method, wherein the step a1) is performed under an atmosphere in which an oxygen concentration is adjusted to 100 ppm or less. The substrate processing method according to claim 1 , wherein:
A substrate processing method, wherein an oxygen concentration in at least one of the removal liquid and the rinsing liquid is reduced to 20 ppb or less. A substrate processing method according to any one of claims 1 to 3,
In the step b), TMSI, BSTFA, BSA, MSTFA, TMSDMA, TMSDEA, MTMSA, TMCS, or HMDS, which are silylated materials, are applied to the main surface. The substrate processing method according to claim 1, wherein:
A substrate processing method, wherein a pattern for a transistor is formed on the silicon substrate.

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