JP5399678B2 - Resist stripping device - Google Patents

Description

This invention relates to a resist stripping device to remove the resist adhering remaining on the substrate.

  For example, in a manufacturing process of a liquid crystal display device or a semiconductor device, a resist is applied to a substrate such as a glass substrate or a semiconductor wafer, which is an object, and a development process is performed before an etching process. A circuit pattern is precisely formed. When the circuit pattern is formed on the substrate, a process of removing organic substances such as a resist film and a resist residue remaining on the surface of the substrate is performed.

When the resist film is removed by washing, sulfuric acid (H ₂ SO ₄ ) and hydrogen peroxide water (H ₂ O ₂ ) are mixed and used as a stripping solution. The stripping solution in which sulfuric acid and hydrogen peroxide are mixed rises to about 100 ° C. by the heat of reaction. When the temperature of the stripping solution rises due to reaction heat, the resist stripping rate can be increased accordingly.

Patent Document 1 discloses a resist removal apparatus that supplies a stripping solution (SPM: Sulfuric acid / Hydrogen peroxide mixture) obtained by mixing sulfuric acid and hydrogen peroxide with a mixing valve to a substrate (semiconductor wafer) from a nozzle. .
JP 2006-278509 A

  SPM made of sulfuric acid and hydrogen peroxide produced by mixing sulfuric acid and hydrogen peroxide is well known as a resist stripping solution. However, the SPM generated by mixing sulfuric acid and hydrogen peroxide is in a liquid state. Therefore, if the processing liquid is supplied from the nozzle to the substrate in a liquid state, if the processing liquid has fine irregularities such as a wiring pattern formed on the substrate, the substrate does not sufficiently enter the irregularities. In some cases, the resist remaining in the substrate cannot be removed reliably and quickly.

The present invention, resist stripping even with minute details in the substrate can remove the resist from the portion that reliably and quickly, yet capable of improving the peeling rate of the resist at a temperature rise due to reaction heat of the superheated steam To provide an apparatus .

The present invention is a resist removing apparatus for removing a resist remaining on a surface of a substrate,
Sulfuric acid supply means for supplying sulfuric acid to the substrate;
Ozone gas supply means for supplying ozone gas for atomizing the sulfuric acid supplied to the substrate;
Superheated steam supply means for supplying reaction heat by supplying superheated steam together with the sulfuric acid and ozone gas to the substrate ;
A mixed injection nozzle body for mixing the sulfuric acid, ozone gas and superheated steam and supplying the mixed substrate to the substrate;
The resist stripping apparatus is characterized by comprising:

  According to this invention, sulfuric acid is atomized with ozone gas to form a stripping solution, and superheated steam is supplied to the atomized sulfuric acid to generate reaction heat. According to the stripping solution that is atomized by mixing ozone gas with sulfuric acid, it can penetrate into the fine irregularities of the substrate sufficiently, so that the stripping effect can be improved, and the stripping solution is mixed with superheated steam. Since the temperature rises due to the generated reaction heat, the resist stripping rate can be increased.

  An embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a spin processing apparatus according to an embodiment of the present invention, and this spin processing apparatus includes a cup body 1. A plurality of discharge pipes 2 are connected to the bottom of the cup body 1 at a predetermined interval in the circumferential direction. Each discharge pipe 2 communicates with an exhaust pump (not shown).

  The cup body 1 has a lower cup 1a and an upper cup 1b, and the upper cup 1b can be driven in the vertical direction by a driving mechanism such as a cylinder (not shown).

  A rotating table 3 as a holding portion is provided in the cup body 1. A plurality of support members 4 are rotatably provided at predetermined intervals in the circumferential direction on the periphery of the upper surface of the turntable 3. On the upper end surface of each support member 4, a locking pin 5 is provided at a position eccentric from the rotation center of the support member 4, and a support pin 6 is provided at the rotation center.

  The turntable 3 is supplied with a substrate W on which a resist remains after the etching process of the semiconductor wafer or the like is completed. That is, the substrate W is supplied so that the lower surface of the peripheral edge portion is supported by the support pins 6. When the support member 4 rotates in this state, the locking pin 5 rotates eccentrically, so that the outer peripheral surface of the substrate W is held by the locking pin 5.

  The rotary table 3 is rotationally driven by a control motor 11. In the control motor 11, a cylindrical rotor 13 is also rotatably inserted into a cylindrical stator 12, and the rotary table 3 is connected to the rotor 13 via a power transmission member 13a. Yes.

  The rotation of the control motor 11 is controlled by the control device 14. Thereby, the rotary table 3 can be rotated at a predetermined rotational speed by the control device 14.

  A cylindrical fixed shaft 15 is inserted into the rotor 13. A nozzle head 16 positioned on the upper surface side of the rotary table 3 is provided at the upper end of the fixed shaft 15. That is, the nozzle head 16 is provided in a state not interlocked with the rotation of the rotary table 3. The nozzle head 16 is provided with lower nozzle bodies 17 and 18 for ejecting cleaning liquid and gas.

  As a result, the cleaning liquid or gas can be selectively ejected from the lower nozzle bodies 17 and 18 toward the central portion of the lower surface of the substrate W held on the turntable 3. In other words, the lower surface of the substrate W can be cleaned and dried.

  The upper surface side of the rotary table 3 is covered with a turbulent flow prevention cover 19. The turbulent flow prevention cover 19 prevents turbulent flow from occurring on the lower surface side of the substrate W held on the rotary table 3, and the substrate is formed from the lower nozzle bodies 17 and 18 at the central portion thereof. A through hole 20 is formed in the lower surface of W so as to be able to inject cleaning liquid or gas.

  A drive mechanism 23 is provided on the side of the cup body 1. The drive mechanism 23 includes a swinging shaft portion 24 provided with the vertical axis, and an arm body 25 provided with a base end connected to the upper end of the swinging shaft portion 24 and provided horizontally. The lower end of the swing shaft portion 24 is connected to a rotary motor 26 as a swing drive source. The rotation motor 26 is configured to rotate the arm body 25 at a predetermined angle.

  The rotary motor 26 is attached to a movable plate 27 that is slidable in the vertical direction by a linear guide (not shown). The movable plate 27 is driven in the vertical direction by the vertical drive cylinder 28.

  At the tip of the arm body 25, an upper nozzle body 31 for supplying a processing liquid to the upper surface of the substrate W is provided. As shown in FIG. 2, one end of first to third supply pipes 32 to 34 is connected to the upper nozzle body 31.

The other end of the first supply pipe 32 is connected to a first supply part 35 that supplies sulfuric acid, and the other end of the second supply pipe 33 is a second supply part 36 that supplies ozone gas (O ₃ ). It is connected to the. Furthermore, the other end of the third supply pipe 34 is connected to a third supply unit 37 that supplies superheated steam.

  First to third flow control valves 41 to 43 are provided on the other end side of the first to third supply pipes 32 to 34, respectively. The opening degree of each flow control valve 41 to 43 is controlled by the control device 14. Thereby, the flow rates of sulfuric acid, ozone gas and superheated steam supplied to the upper nozzle body 31 can be set.

  First to third heating means 44 to 46 including heaters are provided on one end side of the first to third supply pipes 32 to 34, that is, on the downstream side of the flow rate control valves 41 to 43. Yes. The first heating means 44 heats the sulfuric acid to about 100 ° C., and the second heating means 45 heats the ozone gas to about 100 ° C. The 3rd heating means 46 heats superheated steam to 100-300 degreeC. The heating temperature of sulfuric acid, ozone gas and superheated steam by the first to third heating means 44 to 46 can be set by the control device 14.

  In addition, you may make it the 1st thru | or 3rd heating means 44-46 provide a heat generating coil over the full length of the outer peripheral surface of the 1st thru | or 3rd supply pipes 32-34.

When sulfuric acid, ozone gas, and superheated steam are supplied to the upper nozzle body 31, an active species stripping solution as a stripping solution is generated by the sulfuric acid and the ozone gas. At that time, the stripping solution is atomized by ozone gas and sprayed from the upper nozzle body 31. Furthermore, when superheated steam is supplied to the upper nozzle body 31, the temperature of the stripping solution rises due to reaction heat with the superheated steam.
That is, from the upper nozzle body 31, the stripping liquid atomized by ozone gas and having a temperature increased by the reaction heat with the superheated steam is jetted toward the substrate W.

  The temperature of the stripping solution sprayed from the upper nozzle body 31 toward the substrate W is detected by a temperature sensor 48 provided on the upper nozzle body 31 by a holder 47. A detection signal of the temperature sensor 48 is output to the control device 14. The control device 14 compares the temperature of the stripping solution detected by the temperature sensor 48 with a set temperature preset in the control device 14.

  When the detected temperature is lower than the set temperature, the control device 14 controls the first to third heating means 44 to the heating temperature of sulfuric acid, ozone gas and superheated steam supplied to the upper nozzle body 31 to be high. The heating temperature by 46 is controlled.

  If the temperature of the sulfuric acid is raised, the viscosity of the sulfuric acid is lowered, so that the sulfuric acid is easily atomized by the ozone gas. Increasing the temperature of the ozone gas increases the chemical reaction rate with sulfuric acid, and increasing the temperature of the superheated steam increases the reaction heat generated by the reaction with sulfuric acid and increases the peeling rate.

  In addition, when the temperature of the stripping solution supplied from the upper nozzle body 31 to the substrate W is lower than the set value, only the temperature of the superheated steam among sulfuric acid, ozone gas, and superheated steam is changed, thereby You may make it raise temperature.

  Superheated steam greatly changes the component ratio of gas and liquid due to temperature changes. Therefore, when controlling the temperature of the substrate W, it is most suitable to control the temperature of the superheated steam.

Next, an operation when the resist remaining on the substrate W is removed by the apparatus having the above configuration will be described.
When the etching process is completed and the substrate W with the resist remaining on the upper surface is supplied and held on the rotary table 3, the rotary table 3 is rotated at a predetermined rotational speed and the rotary motor 26 is operated to operate the arm body. 25 is swung over the substrate W. At the same time, sulfuric acid, ozone gas, and superheated steam are supplied to the upper nozzle body 31 provided at the tip of the arm body 25.

  The sulfuric acid and ozone gas supplied to the upper nozzle body 31 are mixed to generate an active species stripping solution, and the stripping solution is atomized by ozone gas. Furthermore, reaction heat is generated in the upper nozzle body 31 by mixing superheated steam together with sulfuric acid and ozone gas.

  Therefore, the stripping solution which is atomized by the ozone gas and is heated by the reaction heat with the superheated steam is jetted and supplied from the upper nozzle body 31 to the substrate W. If the stripping solution is atomized, the resist remaining on the substrate W can be reliably stripped because it easily enters the fine irregularities such as the wiring pattern of the substrate W as compared with the liquid state.

  Moreover, the stripping solution has risen to a predetermined temperature due to the reaction heat with the superheated steam. If the temperature of the stripping solution is high, the stripping rate increases according to the temperature. Therefore, the resist can be reliably and rapidly removed from the substrate W.

  When starting the resist stripping of the substrate W, when the third flow rate control valve 43 is opened and superheated steam is supplied to the upper nozzle body 31, the third supply unit 37 and the third flow rate in the third supply pipe 34 are supplied. In some cases, the superheated steam remaining between the control valves 43 is supplied in a state in which the temperature decreases and the ratio of the liquid is large. In that case, until the liquid superheated steam remaining in the third supply pipe 34 finishes flowing out from the upper nozzle body 31, the temperature of the stripping solution does not rise sufficiently, and the stripping action may not be stable.

  Therefore, when the supply of the stripping solution is started, the superheated steam remaining in the third supply pipe 34 is reheated by the third heating means 46 and supplied to the upper nozzle body 31. Accordingly, the liquid superheated steam remaining in the third supply pipe 34 is vaporized again, and the temperature rises and is supplied to the upper nozzle body 31, so that the superheated steam is mixed with sulfuric acid in the upper nozzle body 31. By doing so, the reaction heat by reaction with this sulfuric acid can be generated reliably.

  Moreover, the temperature of the sulfuric acid remaining in the first supply pipe 32 is lowered at the start of peeling. Since the temperature-lowered sulfuric acid has a high viscosity, it may be difficult to be atomized even when mixed with ozone gas by the upper nozzle body 31.

  Therefore, when supply of the stripping solution is started, sulfuric acid remaining in the first supply pipe 32 is heated by the first heating means 44 and supplied to the upper nozzle body 31. Since the heated sulfuric acid has a reduced viscosity, it is sufficiently atomized by the ozone gas by the upper nozzle body 31 and supplied to the substrate W.

  Further, when the ozone gas remaining in the second supply pipe 33 is heated by the second heating means 45 provided in the second supply pipe 33 for supplying the ozone gas, when the peeling liquid is generated by mixing with sulfuric acid. Since the reaction rate can be increased, the amount of supply per unit time can be increased. In addition, since the temperature of the stripping solution increases according to the heating temperature of the ozone gas, the stripping rate can be increased by the temperature increase.

  When the supply of sulfuric acid, ozone gas, and superheated steam to the upper nozzle body 31, that is, the supply of the peeling liquid from the upper nozzle body 31 to the substrate W is started, the temperature of the peeling liquid is detected by the temperature sensor 48.

When the temperature of the stripping liquid detected by the temperature sensor 48 is lower than the set temperature set in the control device 14, the superheated steam generated by at least the third heating unit 46 among the first to third heating units 44 to 46. The temperature for heating is increased. As a result, the temperature of the stripping solution supplied from the upper nozzle body 31 to the substrate W increases according to the temperature of the superheated water vapor, thereby preventing the resist stripping rate from decreasing.

  When the temperature of the stripping liquid detected by the temperature sensor 48 is lower than the set temperature set in the control device 14, not only the superheated steam but also the first and second heating means 44, 45 cause the upper nozzle body 31 to You may make it raise the temperature of the sulfuric acid and ozone gas which are supplied.

  Increasing the temperature of sulfuric acid and ozone gas not only reduces the viscosity of sulfuric acid and increases the reaction rate between sulfuric acid and ozone gas, but also increases the stripping solution temperature, thereby increasing the stripping rate. Further, the atomization of sulfuric acid can be promoted.

  When the temperature of the stripping liquid detected by the temperature sensor 48 is lower than the set temperature set in the control device 14, all of sulfuric acid, ozone gas and superheated steam by the first to third heating means 44 to 46 are used. The heating temperature may be increased.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram of the processing apparatus which shows one embodiment of this invention. The piping system diagram which supplies sulfuric acid, ozone gas, and hydrogen peroxide water to an upper nozzle body.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Cup body, 3 ... Rotary table, 14 ... Control apparatus (control means), 25 ... Arm body, 26 ... Rotation motor (oscillation drive source), 31 ... Upper nords body, 32 ... 1st supply pipe (sulfuric acid) Supply means), 33 ... second supply pipe (ozone gas supply means), 34 ... third supply pipe (superheated steam supply means), 35 ... first supply section (sulfuric acid supply means), 36 ... second supply Part (ozone gas supply means), 37 ... third supply part (superheated steam supply means), 44 ... first heating means, 45 ... second heating means, 46 ... third heating means, 48 ... temperature sensor.

Claims (4)

A resist removing apparatus for removing a resist remaining on a surface of a substrate,
Sulfuric acid supply means for supplying sulfuric acid to the substrate;
Ozone gas supply means for supplying ozone gas for atomizing the sulfuric acid supplied to the substrate;
Superheated steam supply means for supplying reaction heat by supplying superheated steam together with the sulfuric acid and ozone gas to the substrate ;
A mixed injection nozzle body for mixing the sulfuric acid, ozone gas and superheated steam and supplying the mixed substrate to the substrate;
A resist stripping apparatus comprising: A first flow rate control valve for controlling the flow rate of the sulfuric acid supplied to the substrate by the sulfuric acid supply means;
A second flow rate control valve for controlling the flow rate of the ozone gas supplied to the substrate by the ozone gas supply means;
A third flow rate control valve for controlling the flow rate of the superheated steam supplied to the substrate by the superheated steam supply means;
The resist stripping method according to claim 1, further comprising: a control unit configured to control the first to third flow control valves to set a flow rate of each fluid supplied from the supply units to the substrate. apparatus.   3. The resist stripping according to claim 2, further comprising heating means for heating at least superheated steam among the fluids of sulfuric acid, ozone gas and superheated steam that have passed through the first to third flow control valves. apparatus. 4. The resist stripping according to claim 3, further comprising a temperature sensor for detecting a temperature of the fluid supplied to the substrate, and controlling the heating temperature of the fluid by the heating means based on the detection of the temperature sensor. Equipment .

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