JPH11345763A - Treating apparatus for semiconductor substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To variably manage flow speed by controlling a suction port to a suitable opening at treating. SOLUTION: A cup 4 containing a wafer 3 has a throttling mechanism 10, having a plurality of blades provided above and an exhaust port 5. A flow speed of a gas flowing in the cup 4 is varied by altering the open state of the mechanism 10 at each step. Thus, a mist can be exhausted without adversely affecting a resist film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor substrate processing apparatus, and more particularly to a resist coating apparatus used in a photolithography process and an exhaust method of a developing apparatus.

[0002]

2. Description of the Related Art In order to pattern a laminated film formed on a semiconductor substrate, a photolithography technique for forming a pattern composed of a resist film has been used.

The flow of a conventional general photolithography process will be briefly described. First, in order to remove moisture adsorbed on a substrate to be processed (hereinafter, referred to as a wafer), a temperature of 1
After high-temperature baking under the condition of 00 ° C or higher, HMDS is applied to improve the adhesion to the resist film.
(Hexamethyldisizaran) treatment.

[0004] After that, a positive or negative resist is applied to an arbitrary thickness, and a remaining solvent is removed by baking. Thereafter, a desired circuit pattern is exposed using a sequential moving exposure apparatus (commonly called a step-and-repeat type stepper, hereinafter referred to as a stepper).

Next, at a temperature of about 100 ° C., PE
After performing B (post-exposure baking), in the case of a positive resist, the TMAH (tetramethyl ammonium hydroxide) concentration is generally 2.38%.
A resist pattern is completed by performing development using an aqueous alkaline solution consisting of front and rear portions.

Next, of the resist coating process and the developing process in the photolithography process according to the conventional method described above, the resist coating process will be described in more detail with reference to FIG. 5 as an example.

In the configuration of the conventional apparatus shown in FIG. 5, a wafer 103 as a substrate to be processed is placed on a wafer chuck 102 connected to a spin motor 101 after centering, and then vacuum-adsorbed. Is fixed and held.

Next, the resist is dropped on the wafer 103 by either a static dispense method in which the resist is dropped while the wafer 103 is stationary or a dynamic dispense method in which the resist is dropped while rotating the wafer 103 at a low speed. After that, the treatment is performed at a rotation speed at which a desired film thickness is obtained. Thereby, the wafer 103
A resist film having a uniform thickness is formed thereon.

At this time, removal of the resist wrapped around the smooth surface of the wafer 103 (indicating the side surface of the wafer) and particles (dust generation) caused by contact between the resist and a clamp used for holding the wafer 103 by various devices. In order to suppress the above, the resist is removed by an arbitrary number of millimeters at the outer peripheral portion on the resist application surface side. For this reason, the resist is locally removed by discharging alkylpyrrolidone, xylene, ethyl cellosolve acetate, propylene glycol monomethyl ether acetate, ethyl lactate, or the like as an organic solvent from a rinse nozzle (not shown).

Further, regarding the back side of the wafer 103,
In order to remove various mist and adhered particles, a backside rinse process (hereinafter referred to as “backside rinse”) is performed by ejecting an organic solvent through the backside rinse nozzle 107, and then a series of processes are performed by performing a swing-off rotation process. Complete.

Note that the excess resist and the rinsing liquid comprising the organic solvent generated during the above-described process are discharged to the drain tank via the drain port 106.

In addition, in the above-mentioned steps, the surplus resist bounces from the inner wall of the cup, and also the purpose of protecting the surface of the wafer 103 from the bounce of the organic solvent and the atmosphere during the rinsing process. , Forced exhaust is performed using the exhaust port 105.

However, since this exhaust greatly affects the uniformity of the resist coating film thickness, the uniformity of the coating film thickness is given top priority, and the exhaust damper 108 is adjusted in order to obtain an appropriate exhaust gas free of mist and the like. Thus, a method of optimizing the resist film thickness has been adopted.

As described above, the exhaust gas in the resist coating apparatus plays an important role, and the exhaust gas is also intensively controlled in the developing apparatus from the viewpoint of uniformity of the line width of the resist pattern, suppression of mist, and the like. That is the current situation.

[0015]

As described above, in the case of a resist coating apparatus as an example, the processing is performed in such a manner that the first priority is given to the resist coating characteristic and an appropriate exhausting is performed so as not to generate mist as much as possible. As shown in FIG. 6, the organic solvent 121 discharged from the back rinse nozzle 107 and the front rinse nozzle 109 scatters and rebounds on the inner wall of the cup 104 and adheres to the resist 110 on the wafer 103 as a mist 122. That could not be suppressed.

Therefore, it is conceivable to increase the exhaust gas only during the rinse dispensing process excluding the resist dispensing process or the spin coating process which affects the uniformity of the coating film thickness. It had to be strengthened, and the utility capacity had to be increased, and there was a problem that a large financial burden was imposed.

Even if the method of increasing the exhaust is used, the exhaust method of each of the existing devices is either "1" or "O" for opening and closing the damper 108, as shown in FIG. This method has a problem that it is not possible to perform arbitrary exhaust adjustment for each processing step.

Here, the developing device is described in
Japanese Patent Application Laid-Open No. 94515/94 discloses a resist coating apparatus.
0, JP-A-9-260276, JP-A-9-260276
Japanese Patent Application Laid-Open No. 260277 discloses a device applicable to both a developing device and a resist coating device.
Attempts to solve the above problems have been made in, for example, Japanese Patent No. 63941.

However, in any of the methods, the purpose is to improve the flow velocity direction and the flow velocity by changing the mechanism, structure, and the like in the cup, and there is no mechanism capable of arbitrarily varying the flow velocity. It had some of the same problems as the prior art.

The present invention has been made in view of the above problems, and has an arbitrarily variable diaphragm mechanism provided above a cub.
The purpose of the present invention is to variably control the flow rate by controlling an appropriate opening at each processing step.

[0021]

A semiconductor substrate processing apparatus according to the present invention is a processing apparatus for forming a resist film by dropping a resist on a semiconductor substrate and performing a spin coating process, and surrounds the semiconductor substrate. It has a cup, an exhaust port provided in the cup, and a suction port provided above the cup and comprising a throttle mechanism whose opening state is variable.

A processing apparatus for a semiconductor substrate according to the present invention is a processing apparatus for performing a developing process by dropping a developing solution onto a semiconductor substrate, comprising: a cup surrounding the semiconductor substrate; and an exhaust port provided in the cup. And a suction port provided above the cup and comprising a throttle mechanism whose opening state is variable.

In one embodiment of the apparatus for processing a semiconductor substrate according to the present invention, the aperture mechanism may include a step of locally removing the resist film after spin-coating the resist film or a step of cleaning the back surface of the semiconductor substrate. The opening diameter is set to be smaller than in the resist coating step.

In one embodiment of the apparatus for processing a semiconductor substrate of the present invention, the aperture mechanism is set so that an opening diameter is smaller in a cleaning step in the developing process than in the developing process.

In one embodiment of the apparatus for processing a semiconductor substrate according to the present invention, the aperture mechanism comprises a plurality of blades.
The tip of the opening is closer to the semiconductor substrate than the periphery of the aperture mechanism.

[0026]

According to the present invention, it is possible to arbitrarily change the flow rate by arbitrarily changing the ventilation port even under the same exhaust pressure without increasing the exhaust pressure on the utility side. By performing the rinsing-related processing, the flow velocity serves as an air curtain for the mist, and the mist can be forcibly discharged.

Further, the cross-sectional shape of the throttle mechanism is inverted triangular or concave, and the tip of the opening is structured so as to be closer to the wafer, thereby converging the air flow and increasing the flow velocity of the air flow flowing into the cup. In addition, it is possible to improve the flow velocity from the central portion of the wafer to the outer peripheral portion, thereby suppressing mist.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a semiconductor substrate processing apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view illustrating a configuration of a semiconductor substrate processing apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view illustrating a planar configuration of the semiconductor substrate processing apparatus, as viewed from an upper surface of a wafer. is there.

The greatest difference between the processing apparatus shown in FIGS. 1 and 2 and the conventional apparatus is that a freely variable diaphragm mechanism 10 is provided above the cup 4.

The freely variable aperture mechanism 10 is composed of a plurality of blades, similarly to an aperture mechanism used in a photographing machine or the like. The freely variable aperture mechanism 10 can be arbitrarily opened and closed by instructing each step of a processing process on a program set in the resist coating apparatus or the developing apparatus, and the opening degree (aperture). The aperture is also set as a mechanism that can be set to any degree of opening.

As shown in FIG. 1, the aperture mechanism 10 has an inverted triangular shape such that the center of the opening is closest to the wafer.
Or has a concave cross-sectional shape. That is, as shown in FIGS. 1 and 2, when the degree of opening is reduced so that the aperture of the aperture mechanism 10 is reduced,
The tip of the blade at the opening of the aperture mechanism 10 is located below the peripheral portion. As a result, the above-described inverted triangular shape or concave shape is formed.

Next, a resist coating process or a developing process using this processing apparatus will be described together with reference to FIGS.

First, as shown in FIG. 3, in a steady state, the freely variable aperture mechanism 10 is fully opened. In this steady state, the centered wafer 3 is placed on the wafer chuck 2 and vacuum suction is performed. Is held at.

Thereafter, when used as a resist coating apparatus, a resist is dropped from a resist nozzle, and spin coating is performed at a rotation speed such that a desired film thickness is obtained.
When used as a developing device, a developing solution is dropped from a developing solution injection nozzle, and paddling development consisting of stationary or very low speed rotation is performed over a desired specified developing time.

The exhaust during the above-mentioned processing is performed by fully opening the freely variable throttle mechanism 10 and adjusting the exhaust damper 8 to obtain an appropriate exhaust pressure, or by fully opening the exhaust damper 8 to achieve uniform coating film thickness. Either method is used in which the freely variable aperture mechanism 10 is stopped down and set arbitrarily within a range in which no influence occurs.

Next, in the case of using for resist coating, as shown in FIG. 4, before the next step of rinsing with an organic solvent, the freely variable aperture mechanism 10 is moved to the desired opening 11 as shown in FIG. Close to obtain.

Similarly, if it is used for development, as shown in FIG. 4, before the rinsing step with pure water is started, the freely variable aperture mechanism 10 is moved so that the desired opening 11 can be obtained. Close and subsequently perform the rinsing process.

At this time, the back surface rinsing is performed by the back surface cleaning nozzle 7 and the pure water discharge when used as a developing device is performed by discharging from the opening 11 of the freely variable aperture mechanism 10. .

When applying to the resist coating apparatus, when performing top side rinsing, a rinsing nozzle is provided inside the cup 4 or an opening is provided in a part of the freely variable type diaphragm mechanism 10. The rinsing nozzle is lowered through the opening to perform a top side rinsing process.

By adopting such a method, as compared with the state where the aperture mechanism 10 shown in FIG. 3 is open, the aperture 11 of the aperture mechanism 10 shown in FIG.
The flow velocity from the center of the wafer 3 toward the exhaust port 5 is increased. This makes it possible to eliminate mist generated at the time of rinsing at an increased flow rate.

The above-described method has been described by taking as an example the case where the aperture mechanism 10 is fully opened or fully closed (however, the central portion is partially opened). However, the aperture of the aperture 11 of the aperture mechanism 10 can be set arbitrarily. Therefore, the opening 11 of the freely variable diaphragm mechanism 10 can be arbitrarily changed and used so that the most suitable flow rate can be obtained for each processing step.

[0042]

According to the present invention, a rinsing process using an organic solvent in a resist coating process, a shaking-off process,
In addition, it is possible to increase the flow rate of the gas flowing in the cup at the time of the pure water washing process and the shake-off process in the developing process. As a result, unnecessary mist can be forcibly discharged to the outer peripheral portion of the cup and the drain portion, thereby suppressing mist adhesion from the inner wall of the cup and suppressing the occurrence of pattern defects caused by the mist. Becomes

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an apparatus for processing a semiconductor substrate according to the present invention.

FIG. 2 is a schematic plan view showing a semiconductor substrate processing apparatus according to the present invention.

FIG. 3 shows a semiconductor substrate processing apparatus according to the present invention.
It is a schematic sectional view explaining the state of the air current when the throttle mechanism is fully opened.

FIG. 4 shows a semiconductor substrate processing apparatus according to the present invention.
It is a schematic sectional view explaining the state of the air current when the throttle mechanism is closed.

FIG. 5 is a schematic sectional view showing a conventional semiconductor substrate processing apparatus.

FIG. 6 is a schematic sectional view showing a main part of a conventional semiconductor substrate processing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spin motor 2 Wafer chuck 3 Wafer 4 Cup 5 Exhaust port 6 Drain port 7 Backside rinsing nozzle 8 Exhaust damper 10 Throttling mechanism 101 Spin motor 102 Wafer chuck 103 Wafer 104 Cup 105 Exhaust port 106 Drain port 107 Backside rinsing nozzle 108 Exhaust damper 109 Surface rinse nozzle 110 Resist 121 Rinse liquid 122 Mist

Claims (5)

[Claims] 1. A processing apparatus for forming a resist film by dropping a resist on a semiconductor substrate and performing a spin coating process, comprising: a cup surrounding the semiconductor substrate; an exhaust port provided in the cup; A processing device for processing a semiconductor substrate, comprising: a suction port provided above a cup, the suction port including a diaphragm mechanism whose opening state is variable. 2. A processing apparatus for performing a developing process by dropping a developing solution onto a semiconductor substrate, comprising: a cup surrounding the semiconductor substrate; an exhaust port provided in the cup; and an upper port provided above the cup. And a suction port having a diaphragm mechanism whose opening state can be varied. 3. The aperture mechanism has a smaller opening diameter in a step of locally removing the resist film after the spin coating of the resist film or in a step of cleaning the back surface of the semiconductor substrate than in the step of applying the resist. 2. The apparatus for processing a semiconductor substrate according to claim 1, wherein the setting is performed as follows. 4. The semiconductor substrate processing apparatus according to claim 2, wherein the aperture mechanism is set such that an opening diameter is smaller in the cleaning process in the developing process than in the developing process. . 5. The aperture mechanism according to claim 1, wherein the aperture mechanism comprises a plurality of blades, and a tip of an opening is closer to the semiconductor substrate than a peripheral portion of the aperture mechanism. 2. The apparatus for processing a semiconductor substrate according to claim 1.