JP2807675B2 - Resist processing equipment - Google Patents

Description

The present invention relates to a resist processing apparatus such as a resist coating apparatus, an exposure apparatus, and a development processing apparatus.

(Prior art) Resist coating on an object to be processed such as a semiconductor wafer,
Processing such as exposure and development is performed in a clean room in which a vertical laminar flow is constantly supplied to prevent generation of fine dust and the like.

FIG. 2 shows a resist processing apparatus used when applying a resist to the surface of a semiconductor wafer as an example of an apparatus used in such a clean room.

As shown in the figure, the resist processing apparatus is provided with a cup 2 having an opening 1 at an upper portion and having a shape inclined inward. At the edge of the lower surface of the cup 2, an end is connected to a cylindrical exhaust pipe 3 connected to an exhaust mechanism (not shown) and an end is connected to a drain box 4 made of vinyl chloride or the like for accommodating a used resist. The provided cylindrical discharge pipe 5 is provided. A spindle insertion hole 6 is formed at the center of the cup 2.

A wafer chuck 8 made of resin or the like which holds the semiconductor wafer 7 so as to be able to be sucked is inserted into the spindle insertion hole 6. A spindle motor 10 that operates inside is mounted.

A resist supply pipe 11 made of tetrafluoroethylene resin or SUS is disposed above the opening 1 of the cup 2. One end of the resist supply pipe 11 has a resist temperature for adjusting the temperature of the resist. At the other end, a resist drop nozzle 13 for dropping a resist on the surface of the semiconductor wafer 7 from the opening 1 toward the center of the semiconductor wafer 7 is provided.

Above the opening 1 of the cup 2, a temperature / humidity control unit 15 for controlling the temperature and humidity after forcibly taking in the vertical laminar flow 14 supplied from a ceiling (not shown) is arranged. I have.

When a resist is applied to the semiconductor wafer 7 by the resist processing apparatus having such a configuration, first, the vertical laminar flow 14 is forcibly taken into the temperature / humidity control unit 15 and the temperature and humidity of the taken vertical laminar flow 14 are measured. Control and drain,
Send into cup 2.

Next, the semiconductor wafer 7 is transferred onto the wafer chuck 8 by a belt or the like, and then placed at a predetermined position on the wafer chuck 8, and thereafter, is suction-held by a suction mechanism obtained by a vacuum mechanism (not shown).

At this time, in order to facilitate the transfer of the semiconductor wafer 7, the cup 2 has been lowered in advance, and after the semiconductor wafer 7 is sucked and held, the cup 2 is raised.

Thereafter, a resist is dropped from the resist dropping nozzle 13 onto the central portion of the held semiconductor wafer 7.

Here, the resist is sent from a resist supply source (not shown) to the resist temperature controller 12, and is adjusted to, for example, about 24 ° C. by circulating constant temperature water inside the resist temperature controller 12. At this time, the temperature of about 10 cc of the resist is adjusted at a time. However, by circulating the resist in a serpentine or spiral shape, the temperature control capacity increases, so that the temperature can be adjusted more efficiently.

After the resist adjusted to the set temperature by the resist temperature controller 12 is dropped from the resist dropping nozzle 13 onto the surface of the semiconductor wafer 7 by about 3 cc, the spindle motor 10
Is driven at, for example, about 4000 rpm, the semiconductor wafer 7 is rotated at a high speed via the output shaft 9, and the dropped resist is diffused by centrifugal force.

By continuing this, the resist diffused on the semiconductor wafer 7 is dried.

Subsequently, the semiconductor wafer 7 having a surface coated with a resist and dried is conveyed by a belt or the like to an exposure device (not shown), where the surface is subjected to pattern exposure.

Further, the semiconductor wafer 7 that has been subjected to the pattern exposure is conveyed by a belt or the like to a development processing apparatus (not shown), where the semiconductor wafer 7 is suction-held by a wafer chuck with the surface to be developed of the semiconductor wafer 7 facing upward. And while stopping or rotating at low speed the motor connected to the wafer chuck,
A developing solution is supplied to the surface to be developed by a spray nozzle or the like, and thereafter, the semiconductor wafer 7 is rotated at a high speed by a driving force of a motor. As a result, the developer supplied to the surface to be developed is removed by centrifugal force, and a pattern having a thickness of about several μm is formed.

(Problems to be Solved by the Invention) However, in the conventional resist processing apparatus described above, the semiconductor wafer 7 is held by the wafer chuck 8 by a belt or the like.
When the semiconductor wafer 7 is conveyed up and held by suction, the semiconductor wafer 7 rubs against the belt, the wafer chuck 8 and the like, so that the surface thereof is charged with static electricity, so that fine dust and the like are adsorbed on the surface.

As described above, when dust or the like is adsorbed on the surface of the semiconductor wafer 7, the film thickness of the resist becomes non-uniform or the exposure in the exposure apparatus is out of focus, and the quality, yield, and productivity are reduced. However, there is a problem that is reduced.

The present invention has been made in view of such circumstances, and has as its object to provide a resist processing apparatus capable of improving the quality, yield, and productivity of an object to be processed.

[Structure of the Invention] (Means for Solving the Problems) A resist processing apparatus according to the present invention is a resist processing apparatus that sends a vertical laminar flow to a resist processing atmosphere and performs a resist process while rotating an object to be processed. A vertical laminar flow forming apparatus that forms a vertical laminar flow by incorporating air, a filter for removing dust, an ion generator for ionizing air, a heat exchanger for dehumidifying air, and air. A vertical laminar flow forming device configured to pass, in this order, a portion provided with a humidifying mechanism for adding steam to the air, and a heat exchanger for adjusting air to a desired temperature. is there.

(Operation) In the resist processing apparatus of the present invention, the downflow of the ionized air can neutralize the static electricity on the surface of the object to be processed. it can.

(Example) Hereinafter, an example of a resist processing apparatus of the present invention will be described in detail with reference to the drawings.

A pre-filter 17 for filtering the vertical laminar flow 14 is provided inside a rectangular cylindrical housing 16 of the temperature and humidity control unit 15. Below the pre-filter 17, fans 18 and 18 forcibly taking in the vertical laminar flow 14 therein, a damper 19 for buffering the vertical laminar flow 14 taken in by the fan 18, and a damper 19 An ion generator 20 for ionizing the vertical laminar flow 14 is arranged in this order.

Below the ion generator 20, the moisture of the vertical laminar flow 14 ionized by the ion generator 20 is removed by dew condensation by circulation of constant temperature water at a desired temperature by a cooler 21 provided outside the housing 16. A heat exchanger 22 is provided.

Below the heat exchanger 22, a humidification pipe 24 having a plurality of holes 23, 23 for adding vapor such as a solvent of a photoresist to the vertical laminar flow 14 dehumidified by the heat exchanger 22 is arranged. At the end of the humidifying tube 24, a humidifier 25 which is provided outside the housing 16 and generates steam by ultrasonic waves or the like is attached.

Below the humidifier tube 24, a heat exchanger 26 for heating the vertical laminar flow 14 to which steam has been added by the humidifier tube 24 is provided. A temperature controller 27 for circulating constant-temperature water at a desired temperature is provided in the heat exchanger 26.

Below the heat exchanger 26, a heat and humidity detection sensor 28 for detecting the temperature and humidity of the vertical laminar flow 14 controlled by the heat exchanger 22, the humidifying tube 24 and the heat exchanger 26, and a filter 29 including a HEPA filter and the like are provided. They are arranged in this order.

The ion generator 20, the cooler 21, the temperature controller 27, and the like are controlled by a control unit (not shown) connected to the temperature / humidity detection sensor 28 via the cable 30.

Next, the operation of the resist coating apparatus including the temperature and humidity control unit 15 having such a configuration will be described.

As described with reference to FIG. 2, the semiconductor wafer 7 is transported onto the wafer chuck 8 by a transport mechanism such as a belt and held by the wafer chuck 8, and then the resist is dropped from the resist dropping nozzle 13 to the center of the semiconductor wafer 7. The resist is dropped. The exhaust in the cup 2 during such processing is performed by an exhaust pipe 3 according to a set program.
Through an exhaust mechanism (not shown).

The resist scattered by the rotation of the semiconductor wafer 7 adheres to the inner surface of the cup 2 inclined inward and falls down by its own weight when the thickness increases to some extent, and is stored in the drain box 4 via the discharge pipe 5. .

Here, when the resist coating in the cup 2 is always performed in a clean state, the vertical laminar flow 14 forcibly taken in by each fan 18 through the pre-filter 17 is first buffered by the damper 19, It is ionized by the ion generator 20. Next, after the ionized vertical laminar flow 14 is dehumidified by the heat exchanger 22, a vapor such as a photoresist solvent from the plurality of holes 23 of the humidifying tube 24 is added thereto, and further heated by the heat exchanger 26. , Temperature detection sensor 28
And, it is discharged downward through the filter 29 and sent into the cup 2.

As a result, the temperature and humidity are controlled and the inside of the cup 2 is filled with the ionized vertical laminar flow 14, so that the semiconductor wafer 7 rubs against the belt or the wafer chuck 8 and the like, and the static electricity on the surface is ionized. Neutralization can be performed by the vertical laminar flow 14 thus prevented, and adsorption of fine dust and the like to the surface thereof is prevented.

As described above, in the present embodiment, the temperature and humidity control unit 15
The vertical laminar flow 14 to be sent to the cup 2 can be ionized by the ion generator 20 provided therein, so that the static electricity charged on the surface of the semiconductor wafer 7 can be neutralized, and Adsorption of fine dust and the like can be prevented.

Further, in the resist coating apparatus of this embodiment, the temperature and humidity control unit 15 provided in the apparatus can keep the atmosphere in the cup 2 constant even when the temperature and humidity in the clean room fluctuate.

Further, in the present embodiment, the cleanness inside the cup 2 can be locally improved by the pre-filter 17 and the filter 29 provided in the temperature / humidity control unit 15.

In this embodiment, the heat exchanger 22 is circulated by circulating constant temperature water.
Although the case of controlling the temperature and humidity using the humidifier 25 using ultrasonic waves or ultrasonic waves has been described, the temperature and humidity may be controlled using a Peltier element, bubbling, or the like, without being limited to this example.

In the present embodiment, the case where the present invention is applied to a resist coating apparatus has been described. However, the present invention is not limited to this example, and may be applied to other resist processing apparatuses such as an exposure apparatus and a developing apparatus. In this case, the uniformity of the developed pattern and the uniformity of the development can be improved.

[Effects of the Invention] As described above, according to the resist processing apparatus of the present invention, adsorption of dust and the like can be prevented, so that the quality, yield, and productivity of an object to be processed can be improved.

[Brief description of the drawings]

FIG. 1 is a detailed view of a temperature / humidity control section showing an embodiment in which the resist processing apparatus of the present invention is applied to a resist coating apparatus, and FIG. 2 is a diagram simply showing a conventional resist coating apparatus. 1 ... opening, 2 ... cup, 3 ... cylindrical exhaust pipe, 4
... Drain box, 5 ... Cylindrical discharge tube, 7 ... Semiconductor wafer, 8 ... Wafer chuck, 9 ... Output shaft, 10
…… Spindle motor, 11 …… Resist supply pipe, 12
… Resist temperature controller, 14… vertical laminar flow, 15… temperature and humidity control section, 17… prefilter, 18… fan, 19… damper, 20… ion generator, 21… cooler , 22 ... heat exchanger, 24 ... humidifier tube, 25 ... humidifier, 26
…… Heat exchanger, 27 …… Temperature controller, 28 …… Temperature and humidity detection sensor, 29 …… Filter

Claims (1)

(57) [Claims] 1. A resist processing apparatus for sending a vertical laminar flow to a resist processing atmosphere and performing a resist process while rotating an object to be processed, wherein a vertical laminar flow forming apparatus for taking in air to form a vertical laminar flow. The air taken in is a filter for removing dust, an ion generator for ionizing air, a heat exchanger for dehumidifying air, a humidifying mechanism for adding steam to air, and a heat exchange for adjusting air to a desired temperature. vessel,
A vertical laminar flow forming device configured to pass through the portions provided with the layers in this order.