JP3824510B2 - Substrate processing equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate processing apparatus that performs predetermined processing on the back surface of a substrate.
[0002]
[Prior art]
2. Description of the Related Art A substrate processing apparatus is used to perform various processes on a substrate such as a semiconductor wafer. In a semiconductor device manufacturing process, a substrate processing apparatus such as a coating apparatus that applies a photoresist to a substrate and a developing apparatus that performs a developing process on the substrate is used.
[0003]
In the coating apparatus, the photoresist is spread on the surface of the substrate by discharging a photoresist solution from the resist nozzle to the surface of the substrate while rotating the substrate. Thereafter, a rinsing liquid such as a solvent is discharged from the back rinse nozzle to the back surface of the substrate to clean the back surface of the substrate.
[0004]
In the developing device, the developer is spread on the surface of the substrate by discharging the developer from the developing nozzle to the surface of the substrate while rotating the substrate. Thereafter, the developer is held on the substrate for a certain period of time, and the development proceeds. After the development is completed, the developer is shaken off by rotating the substrate. Then, a rinse liquid such as pure water is discharged from the rinse nozzle onto the surface of the substrate to clean the surface of the substrate, and a rinse liquid such as pure water is discharged from the back rinse nozzle onto the back surface of the substrate to clean the back surface of the substrate. To do.
[0005]
By the way, the substrate may be charged during the manufacturing process of the semiconductor device. Usually, in each processing apparatus, since the substrate is held by a conductive holding unit (chuck), even if the substrate is charged, static electricity is discharged through the holding unit.
[0006]
However, in the semiconductor device manufacturing process, an oxide film may be coated on the back surface of the substrate with high-density plasma. In that case, since there is no electrical continuity between the substrate and the conductive holding portion, the substrate is transported to a subsequent process while the back surface of the substrate is charged with static electricity.
[0007]
When the substrate is transferred to a subsequent ion implantation apparatus in a charged state, the substrate may stick to a holding portion in the ion implantation apparatus due to static electricity, resulting in a substrate conveyance failure. In addition, there is a possibility of causing a defect in the pattern on the substrate due to sparks caused by static electricity.
[0008]
Therefore, ions are generated by using a contact-type static elimination brush, a non-contact-type static elimination brush, a contact-type static elimination ribbon or a non-contact-type static elimination ribbon, or by generating corona discharge with a static eliminator called an ionizer. However, a method of removing static electricity with these ions can be considered.
[0009]
[Problems to be solved by the invention]
However, the contact-type static elimination brush and the contact-type static elimination ribbon are brought into contact with the front surface of the substrate or the back surface of the substrate. Therefore, these contact-type static elimination brushes and contact-type static elimination ribbons are problematic in process management and cannot be used.
[0010]
On the other hand, since the non-contact type static elimination brush and the non-contact type static elimination ribbon perform neutralization without contact, there is a problem that it is difficult to eliminate static electricity when the potential of a charged object is low.
[0011]
According to the method using an ionizer, a spark occurs in the air when a corona discharge occurs. Due to this phenomenon, there is a case where something like a discharge dust falls on the surface of the substrate and causes particles (dust).
[0012]
An object of the present invention is to provide a substrate processing apparatus capable of sufficiently preventing charging of a substrate while keeping the substrate clean.
[0013]
[Means for Solving the Problems and Effects of the Invention]
A substrate processing apparatus according to a first aspect of the present invention is a substrate processing apparatus that performs a predetermined process on a substrate, has conductivity , holds the central portion of the back surface of the substrate, and can rotate the held substrate. A holding means; a back surface cleaning nozzle that discharges the cleaning liquid to the peripheral edge of the back surface of the substrate that is held by the substrate holding means and rotated by the substrate holding means; a gas-liquid mixing device that mixes carbon dioxide with the cleaning liquid; A gas-liquid mixing apparatus for mixing the liquid, a cleaning liquid supply means for supplying the cleaning liquid mixed with carbon dioxide gas by the gas-liquid mixing apparatus to the back surface cleaning nozzle, and a development for supplying the developer to the surface of the substrate held by the substrate holding means Liquid supply means .
[0014]
In the substrate processing apparatus according to the first invention, the substrate is held by the substrate holding means. Carbon dioxide gas is mixed with the cleaning liquid by the gas-liquid mixing device, the cleaning liquid mixed with carbon dioxide gas is supplied to the back surface cleaning nozzle by the cleaning liquid supply means, and the cleaning liquid is discharged from the back surface cleaning nozzle to the back surface of the substrate held by the substrate holding means. Is done. Thereby, the back surface of the substrate is cleaned.
[0015]
In this case, the specific resistance of the cleaning liquid is reduced by mixing carbon dioxide with the cleaning liquid. Thereby, the specific resistance of the back surface of the substrate is lowered by discharging the cleaning liquid mixed with carbon dioxide on the back surface of the substrate, and electrical conduction between the back surface of the substrate and the conductive substrate holding means is obtained. . As a result, charging of the substrate is sufficiently prevented. In addition, since the cleaning liquid mixed with carbon dioxide is discharged to the back surface of the substrate, there is no problem that the surface of the substrate is affected by carbon dioxide bubbles. For this reason, it is possible to sufficiently prevent the substrate from being charged while keeping the substrate clean.
[0016]
Further, in this case, the developer is supplied to the surface of the substrate held by the substrate holding means by the developer supply means. Thereby, it is possible to perform the development process and the back surface cleaning of the substrate together in a state where the substrate is held by the substrate holding means.
[0017]
A substrate processing apparatus according to a second aspect of the invention includes an adjusting means for changing the specific resistance of the cleaning liquid by adjusting the amount of carbon dioxide mixed by the gas-liquid mixing apparatus in the configuration of the substrate processing apparatus according to the first aspect of the invention. It is a waste.
[0018]
In this case, the amount of carbon dioxide mixed in the cleaning liquid is adjusted by the adjusting means provided in the gas-liquid mixing device, and the specific resistance of the cleaning liquid is adjusted. Thereby, the specific resistance of the cleaning liquid can be adjusted to a desired value.
[0019]
A substrate processing apparatus according to a third aspect of the present invention further includes a specific resistance measurement sensor for measuring the specific resistance of the cleaning liquid obtained by the gas-liquid mixing device in the configuration of the substrate processing apparatus according to the first or second aspect of the invention. Is.
[0020]
In the gas-liquid mixing device, the specific resistance of the cleaning liquid is changed by mixing carbon dioxide with the cleaning liquid. In this case, since the specific resistance of the cleaning liquid is measured by the specific resistance measurement sensor, the specific resistance of the cleaning liquid can be managed.
[0021]
The substrate processing apparatus which concerns on 4th invention is the structure of the substrate processing apparatus which concerns on 3rd invention, The washing | cleaning liquid supply piping which supplies the washing | cleaning liquid obtained by the gas-liquid mixing apparatus to a back surface washing nozzle, and a gas-liquid mixing apparatus And a cleaning liquid discharge pipe for discharging the obtained cleaning liquid through the specific resistance measuring sensor.
[0022]
In this case, the cleaning liquid obtained by the gas-liquid mixing apparatus is supplied to the back surface cleaning nozzle via the cleaning liquid supply pipe. Further, the cleaning liquid obtained by the gas-liquid mixing device is discharged through the cleaning liquid discharge pipe and the specific resistance measurement sensor. Accordingly, the cleaning liquid that has passed through the specific resistance measurement sensor is discharged without being supplied to the back surface cleaning nozzle. Therefore, even when the specific resistance measuring sensor is made of metal, the metal component is not supplied to the back surface cleaning nozzle. As a result, it is possible to prevent a metal component not preferable for processing the substrate from being supplied to the substrate.
[0023]
According to a fifth aspect of the present invention, there is provided a substrate processing apparatus, wherein, in the configuration of the substrate processing apparatus according to the third or fourth aspect, an alarm is issued when the specific resistance of the cleaning liquid measured by the specific resistance measurement sensor is outside a predetermined range. Is further provided with a specific resistance alarm output means.
[0024]
In this case, when the specific resistance of the cleaning liquid measured by the specific resistance measuring sensor is out of the predetermined range, an alarm is output by the specific resistance alarm output means. Thereby, the user can know that the specific resistance of the cleaning liquid is not an appropriate value.
[0025]
According to a sixth aspect of the present invention, there is provided a substrate processing apparatus according to any one of the first to fifth aspects, wherein a warning is given when the pressure of the carbon dioxide gas in the gas-liquid mixing apparatus falls outside a predetermined range. Is further provided with a pressure alarm output means.
[0026]
In this case, when the pressure of the carbon dioxide gas in the gas-liquid mixing apparatus is out of a predetermined range, an alarm is output by the pressure alarm output means. Thereby, the user can know that the pressure of the carbon dioxide gas in a gas-liquid mixing apparatus is not an appropriate value.
[0027]
A substrate processing apparatus according to a seventh aspect of the present invention is the substrate processing apparatus according to any one of the first to sixth aspects, wherein the cleaning liquid is pure water.
[0028]
In this case, since carbon dioxide has a high solubility in pure water, carbon dioxide can be easily mixed with pure water.
[0029]
A substrate processing apparatus according to an eighth invention is the substrate processing apparatus according to any one of the first to seventh inventions, wherein the substrate processing apparatus supplies a rinsing liquid to the surface of the substrate held by the substrate holding means. The rinse nozzle is further provided, the rinse liquid is supplied from the rinse nozzle to the surface of the substrate, and the cleaning liquid is discharged from the back surface cleaning nozzle to the back surface of the substrate.
[0030]
In this case, the rinse liquid is supplied from the rinse nozzle to the surface of the substrate held by the substrate holding unit, and the cleaning liquid is discharged from the back surface cleaning nozzle to the back surface of the substrate.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a block diagram showing a configuration of a substrate processing apparatus according to an embodiment of the present invention.
[0032]
The substrate processing apparatus 1 includes a main panel 100, a main controller 110, a developing device 120, a gas-liquid mixing device 130, a specific resistance measurement sensor 160, and a drain box 170. The substrate processing apparatus 1 is supplied with pure water and carbon dioxide (CO ₂ ) from a pure water supply device 140 and a carbon dioxide supply device 150 provided in the factory.
[0033]
The main panel 100 includes a switch that performs an overall operation of the substrate processing apparatus 1, a display unit that displays an operation status, and an alarm lamp that displays an alarm. An operation signal generated by operating the switch on the main panel 100 is given to the main controller 110 via the signal path C. An alarm signal is given from the main controller 110 to the main panel 100 via the signal path C.
[0034]
The main controller 110 controls the overall operation of the substrate processing apparatus 1 based on an operation signal given from the main panel 100 through the signal path C.
[0035]
The developing device 120 performs development processing on the substrate 121. In the present embodiment, the substrate 121 is a semiconductor wafer. The developing device 120 includes a developing nozzle 122, a conductive substrate holding portion 123, a motor 124, and a back rinse nozzle 125.
[0036]
During the developing process in the developing device 120, the substrate 121 is held by the substrate holding unit 123, and the substrate holding unit 123 is rotationally driven by the motor 124. In this state, the developer is discharged from the developing nozzle 122 onto the surface of the rotating substrate 121. The developer is spread on the surface of the substrate 121 by the rotation of the substrate 121. Thereafter, development proceeds by allowing the developer to remain on the surface of the substrate 121 for a certain period of time. After the development is completed, the developer is spun off by rotating the substrate 121, and a rinse liquid such as pure water is discharged from the rinse nozzle (not shown) onto the surface of the substrate 121, and back rinse is performed on the back surface of the substrate 121. A cleaning liquid described later is discharged from the nozzle 125. Thereby, the front surface and the back surface of the substrate 121 are cleaned. The operation of the developing device 120 is controlled by a control signal given from the main controller 110 via the signal path D.
[0037]
The gas-liquid mixing device 130 mixes carbon dioxide gas supplied from the carbon dioxide supply device 150 via the carbon dioxide supply piping b with pure water supplied from the pure water supply device 140 via the pure water supply piping a. Thus, a cleaning liquid used for cleaning the back surface of the substrate 121 in the developing device 120 is manufactured. The gas-liquid mixing device 130 also manages the specific resistance of the cleaning liquid. The operation of the gas-liquid mixing device 130 is controlled by a control signal given from the main controller 110 via the signal path B. Further, as will be described later, an alarm signal is given from the gas-liquid mixing device 130 to the main controller 110 via the signal path B. Details of the configuration and operation of the gas-liquid mixing device 130 will be described later.
[0038]
The cleaning liquid produced by the gas-liquid mixing device 130 is supplied to the back rinse nozzle 125 of the developing device 120 through the cleaning liquid supply pipe c, and is discharged to the back surface of the substrate 121 held by the substrate holding unit 123. The used cleaning liquid in the developing device 120 is discharged to the drain box 170 through the cleaning liquid discharge pipe e.
[0039]
The specific resistance measurement sensor 160 measures the specific resistance of the cleaning liquid supplied from the gas-liquid mixing apparatus 130 via the cleaning liquid discharge pipe d1, and outputs a signal indicating the specific resistance value to the gas-liquid mixing apparatus 130 through the signal path A. To do. The cleaning liquid that has passed through the specific resistance measurement sensor 160 is discharged to the drain box 170 through the cleaning liquid discharge pipe d2. The drain box 170 collects cleaning liquid that is no longer necessary.
[0040]
As described above, when carbon dioxide gas is mixed with pure water by the gas-liquid mixing device 130, the specific resistance of the cleaning liquid decreases. By discharging the cleaning liquid from the back rinse nozzle 125 to the back surface of the substrate 121, the specific resistance of the back surface of the substrate 121 is reduced, and electrical conduction between the back surface of the substrate 121 and the substrate holding portion 123 is obtained. As a result, charging of the substrate 121 is sufficiently prevented. Further, since the cleaning liquid is discharged onto the back surface of the substrate 121, the surface of the substrate 121 is not affected by carbon dioxide bubbles or the like. Therefore, charging can be sufficiently prevented while keeping the substrate 121 clean.
[0041]
FIG. 2 is a diagram showing a configuration of the gas-liquid mixing device 130 in the substrate processing apparatus 1 of FIG.
[0042]
In FIG. 2, the gas-liquid mixing device 130 includes a pure water control valve 131, a carbon dioxide mixing unit 132 including a carbon dioxide supply module, a carbon dioxide control valve 133, a closing valve 134, and a pressure gauge 135.
[0043]
In the gas-liquid mixing device 130, the pure water sent from the pure water supply device 140 in the factory via the pure water supply pipe a is sent to the carbon dioxide mixing unit 132 via the pure water control valve 131. On the other hand, the carbon dioxide gas sent from the carbon dioxide supply device 150 in the factory via the carbon dioxide supply pipe b is sent to the carbon dioxide mixing unit 132 via the carbon dioxide control valve 133. In the carbon dioxide gas mixing unit 132, pure water and carbon dioxide gas are mixed. In the carbon dioxide gas mixing unit 132, the cleaning liquid mixed with carbon dioxide gas merges with the pure water sent from the pure water supply device 140 in the factory, and is supplied to the cleaning liquid supply pipe c and the cleaning liquid discharge pipe d1. Generation | occurrence | production of the water vapor | steam etc. by a carbon dioxide supply is discharged | emitted by the pressure feed by a carbon dioxide gas through the closing valve 134. FIG.
[0044]
The pressure of the carbon dioxide gas in the carbon dioxide gas mixing unit 132 of the gas-liquid mixing device 130 is adjusted by the carbon dioxide gas control valve 133. The user gives an operation signal for pressure adjustment to the main controller 110 via the signal path C by operating the switch of the main panel 100. The main controller 110 controls the carbon dioxide control valve 133 by providing a control signal for pressure adjustment to the gas-liquid mixing device 130 via the signal path B based on the operation signal. Thereby, the pressure of the carbon dioxide gas in the carbon dioxide gas mixing unit 132 changes.
[0045]
The pressure of the carbon dioxide gas in the gas-liquid mixing device 130 is managed as follows. The pressure gauge 135 measures the pressure of the carbon dioxide gas supplied to the carbon dioxide gas mixing unit 132 and outputs a signal indicating the measured pressure value to the main controller 110 through the signal path B. The main controller 110 determines whether or not the measured value of the pressure of the carbon dioxide gas is within a predetermined pressure setting range based on a signal indicating the measured value of the pressure. When the measured value of the pressure of carbon dioxide gas deviates from a predetermined pressure setting range, the main controller 110 outputs a pressure warning signal to the main panel 100 through the signal path C. The main panel 100 turns on the pressure alarm lamp in response to the pressure alarm signal. Thereby, the user can know that the pressure of the carbon dioxide gas supplied to the carbon dioxide gas mixing unit 132 is out of the set range.
[0046]
The specific resistance of the cleaning liquid obtained by the gas-liquid mixing device 130 is adjusted by the pure water control valve 131. The user gives an operation signal for adjusting the specific resistance to the main controller 110 via the signal path C by operating the switch of the main panel 100. The main controller 110 controls the pure water control valve 131 by providing a control signal for adjusting the specific resistance to the gas-liquid mixing device 130 via the signal path B based on the operation signal. Thereby, the mixing ratio of pure water and carbon dioxide gas changes, and the specific resistance of the obtained cleaning liquid changes.
[0047]
The operation of mixing carbon dioxide gas into pure water by the gas-liquid mixing device 130 is managed by the measured value of the specific resistance by the specific resistance measuring sensor 160. The specific resistance measurement sensor 160 measures the specific resistance of the cleaning liquid sent via the cleaning liquid discharge pipe d1, and outputs a signal indicating the measured value of the specific resistance to the gas-liquid mixing device 130 through the signal path A. The signal indicating the measured value of the specific resistance output to the gas-liquid mixing device 130 is further sent to the main controller 110 via the signal path B. The main controller 110 determines whether or not the measured value of the specific resistance is within a predetermined specific resistance setting range based on a signal indicating the measured value of the specific resistance. When the measured value of the specific resistance deviates from a predetermined specific resistance setting range, the main controller 110 outputs a specific resistance alarm signal to the main panel 100 through the signal path C. The main panel 100 turns on a specific resistance alarm lamp in response to the alarm signal. Thereby, the user can know that the specific resistance of the cleaning liquid is out of the set range.
[0048]
In the present embodiment, a metal material is used for the specific resistance measurement sensor 160. Even in this case, a part of the cleaning liquid obtained by the gas-liquid mixing device 130 is supplied to the back rinse nozzle 125 of the developing device 120 via the cleaning liquid supply pipe c, and another cleaning liquid obtained by the gas-liquid mixing device 130 is supplied. A part is supplied to the specific resistance measurement sensor 160 via the cleaning liquid discharge pipe d1, and the cleaning liquid passing through the specific resistance measurement sensor 160 is discharged to the drain box 170 via the cleaning liquid discharge pipe d2. In this way, the cleaning liquid that has passed through the specific resistance measuring sensor 160 is not supplied to the developing device 120. As a result, it is possible to prevent a metal component not preferable for processing the substrate 121 from being supplied to the developing device 120.
[0049]
Further, the main controller 110 manages power supply to the gas-liquid mixing device 130. The main controller 110 outputs an alarm signal for power supply to the main panel 100 via the signal path C when power supply to the gas-liquid mixing device 130 is interrupted. The main panel 100 turns on the alarm lamp in response to the alarm signal. Thereby, the user can know the interruption of the power supply to the gas-liquid mixing device 130.
[0050]
In the present embodiment, the substrate holding portion 123 corresponds to the substrate holding means, and the back rinse nozzle 125 corresponds to the back surface cleaning nozzle. Further, the carbon dioxide gas control valve 133 corresponds to an adjusting unit, the main panel 100 corresponds to a specific resistance alarm output unit and a pressure alarm output unit, and the developing nozzle 122 corresponds to a developing solution supply unit.
[0051]
In the above embodiment, when the specific resistance of the cleaning liquid deviates from a predetermined setting range, an alarm is output by an alarm lamp. However, an alarm may be displayed by other display means, such as an alarm buzzer. An alarm sound may be output from the sound source.
[0052]
In the above embodiment, an alarm lamp outputs an alarm when the pressure of the carbon dioxide gas supplied to the carbon dioxide gas mixing unit 132 of the gas-liquid mixing device 130 is out of a predetermined setting range. An alarm may be displayed by the display means, and an alarm sound may be output by a sound source such as an alarm buzzer.
[0053]
Further, in the above embodiment, when the power supply to the gas-liquid mixing device 130 is interrupted, an alarm is output by the alarm lamp, but the alarm may be displayed by other display means. An alarm sound may be output by a sound source such as.
[0054]
The present invention can be applied not only to the developing apparatus but also to other substrate processing apparatuses having a function of cleaning the back surface of the substrate.
[0055]
Further, the cleaning liquid is not limited to pure water, and other liquids can be used as long as the carbon dioxide gas dissolves therein.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a substrate processing apparatus in an embodiment of the present invention. FIG. 2 is a diagram showing a configuration of a gas-liquid mixing device in the substrate processing apparatus of FIG.
100 Main Panel 110 Main Controller 120 Developing Device 121 Substrate 122 Developing Nozzle 123 Substrate Holding Unit 124 Motor 125 Back Rinse Nozzle 130 Gas-Liquid Mixing Device 131 Pure Water Control Valve 132 Carbon Dioxide Mixing Unit 133 Carbon Dioxide Control Valve 134 Closing Valve 135 Pressure Gauge 140 Pure water supply device 150 Carbon dioxide supply device 160 Resistivity measurement sensor 170 Drain box A, B, C, D Signal path a Pure water supply piping b Carbon dioxide supply piping c Cleaning liquid supply piping d1, d2, e Cleaning liquid discharge piping

Claims (8)

A substrate processing apparatus for performing predetermined processing on a substrate,
A substrate holding means capable of rotating the substrate to be held and holding the back surface central portion of the substrate while having conductivity;
A back surface cleaning nozzle that is held by the substrate holding means and that discharges the cleaning liquid to the peripheral edge of the back surface of the substrate rotated by the substrate holding means ;
A gas-liquid mixing device that mixes carbon dioxide with the cleaning liquid;
Cleaning liquid supply means for supplying a cleaning liquid mixed with carbon dioxide by the gas-liquid mixing apparatus to the back surface cleaning nozzle ;
A substrate processing apparatus, comprising: a developer supply means for supplying a developer to the surface of the substrate held by the substrate holding means .   The substrate processing apparatus according to claim 1, wherein the gas-liquid mixing apparatus includes an adjusting unit that adjusts a specific resistance of the cleaning liquid by adjusting a mixing amount of carbon dioxide gas.   The substrate processing apparatus according to claim 1, further comprising a specific resistance measurement sensor for measuring a specific resistance of the cleaning liquid obtained by the gas-liquid mixing apparatus. The cleaning liquid supply means includes
A cleaning liquid supply pipe for supplying the cleaning liquid obtained by the gas-liquid mixing device to the back surface cleaning nozzle;
4. The substrate processing apparatus according to claim 3, further comprising a cleaning liquid discharge pipe for discharging the cleaning liquid obtained by the gas-liquid mixing apparatus through the specific resistance measurement sensor.   5. The substrate processing according to claim 3, further comprising specific resistance alarm output means for outputting an alarm when the specific resistance of the cleaning liquid measured by the specific resistance measuring sensor is outside a predetermined range. apparatus.   6. The substrate processing according to claim 1, further comprising a pressure alarm output means for outputting an alarm when the pressure of the carbon dioxide gas in the gas-liquid mixing apparatus falls outside a predetermined range. apparatus.   The substrate processing apparatus according to claim 1, wherein the cleaning liquid is pure water. A rinsing nozzle for supplying a rinsing liquid to the surface of the substrate held by the substrate holding means ;
The substrate processing apparatus according to claim 1, wherein a rinse liquid is supplied from the rinse nozzle to the surface of the substrate, and a cleaning liquid is discharged from the back surface cleaning nozzle to the back surface of the substrate.

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