JP2940620B2 - Liquid processing equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a processing apparatus.

(Prior Art) When a resist is applied to a substrate to be processed, for example, a semiconductor wafer, the surface to be coated of the semiconductor wafer is directed upward and vacuum chucked by a wafer chuck, and the resist is dropped onto the center of the surface to be coated. In this method, the semiconductor wafer is rotated at a high speed by a motor connected to a wafer chuck to spread the resist over the surface to be coated by centrifugal force.
For example, Japanese Patent Application Laid-Open No. Sho 52-144491 discloses a spin coating apparatus that forms a coating film by dropping a coating material and rotating a wafer-shaped object.

When a semiconductor wafer is coated by the above-described resist coating apparatus, there is a problem that the film thickness on the semiconductor wafer becomes non-uniform due to a change in the temperature of the resist. It has been practiced to apply a resist by dropping it on the surface of a semiconductor wafer in a state where the temperature change is eliminated. Such a resist temperature control is well known, for example, from JP-A-61-125017.

(Problems to be Solved by the Invention) However, as in the conventional technology described above, in a semiconductor wafer processing apparatus that rotates a semiconductor wafer by a motor such as a resist coating process or a developing process, the temperature of a resist solution to be coated is controlled. However, the heat transmitted through the drive shaft of the motor connected to the wafer chuck and the radiant heat generated by the motor cause uneven temperature distribution of the semiconductor wafer, which makes it impossible to achieve uniform resist film thickness and reduces the yield. was there.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a liquid processing apparatus that can realize uniform processing and improve the yield.

(Means for Solving the Problems) According to the present invention, in a liquid processing apparatus for supplying and processing a resist liquid on a processing surface of a rotating object to be processed, the resist liquid supplied to the processing surface of the object to be processed is heated and cooled. A first temperature control means for adjusting, a holding member configured to hold the object to be processed and rotatable based on rotation of an output shaft of a motor, and configured to be capable of projecting an output shaft of the motor; A motor contacting member; and a second temperature adjusting means for adjusting a temperature of at least a region of the member contacting the motor, wherein the member thermally separates the motor side from the holding body side. It is characterized by comprising.

According to the present invention, there is provided a liquid processing apparatus for supplying a resist liquid to a processing surface of a rotating object to be processed, wherein the temperature of the resist liquid supplied to the processing surface of the object is adjusted.
A holder for holding the object to be processed and rotatable based on the rotation of the output side of the motor; provided at a position below the holder for projecting the output shaft of the motor. A first member configured to be capable of being used, a second temperature control means for adjusting the temperature of the first member, and a motor provided on the motor side together with the first member, the second member being provided in contact with the first member; And a second member for thermally partitioning the body side.

In these liquid processing apparatuses, the motor can be attached to the member or the first member. Further, the second temperature adjusting means may be configured to circulate constant-temperature water through the inside of the member or the first member.

(Operation) In the liquid processing apparatus of the present invention, the temperature of the resist solution supplied to the processing surface of the object to be processed can be adjusted by the first temperature control means, and the heat transmitted to the output shaft of the motor by the second temperature control means. By controlling the radiation heat of the motor and the motor so as to insulate the heat, it is possible to prevent the temperature of the wafer chuck and the semiconductor wafer from being uneven, and to improve the uniformity of the resist film thickness.

(Embodiment) An embodiment in which the apparatus of the present invention is applied to resist coating of a semiconductor wafer in a semiconductor manufacturing process will be described below with reference to the drawings.

 First, the configuration of the resist coating device will be described.

For example, a resin-made disk-shaped wafer chuck (2) capable of holding a substrate to be processed, for example, a semiconductor wafer (1), for example, by suction holding
Is provided. The wafer chuck (2) is connected to a spin motor (4), for example, an AC servomotor via an output shaft (3). The wafer chuck (2) is rotatably provided at a desired rotation speed of, for example, 0 to 8000 rpm. I have. A cylindrical cup (5) made of, for example, resin or SUS is provided so as to surround the semiconductor wafer (1) held by the wafer chuck (2), and the cup (5) is a surface of the semiconductor wafer (1). Angle A (A ≠
90 ゜). At the bottom of the cup (5), for example, a cylindrical discharge pipe (6a) is provided, and the resist after use is connected to the discharge pipe (6a) via a vertically movable cylindrical discharge pipe (6b). Are connected to, for example, a cubic drain box (7) made of vinyl chloride. Further, at the bottom of the cup (5), for example, a cylindrical exhaust pipe (8) connected to an exhaust mechanism (not shown) for exhausting the inside of the cup (5) is provided.

A resist drop nozzle (9) made of, for example, tetrafluoroethylene resin or SUS is provided so that a resist set on the central axis of the semiconductor wafer (1) can be dropped on the surface of the semiconductor wafer (1). This is in contact with, for example, a cylindrical heat exchanger (10) for controlling the temperature of the resist, which can be adjusted with constant temperature water, for example, to a resist dropping position.
The heat exchanger (10) is connected to the first temperature controller (12) by, for example, urethane resin or rubber tubes (11a, 11b), and the temperature is controlled by the first temperature controller (12). The constant temperature water can be circulated to the heat exchanger (10).

The nozzle (9) is made of, for example, a pipe (13a, 13b, 13c) made of tetrafluoroethylene resin or SUS, a check valve (14) for preventing backflow of resist, and a pump using, for example, an air cylinder or the like. For example, a pump (16) using a verose or diaphragm equipped with a drive mechanism (15) and a tank (1) equipped with two non-contact liquid level sensors (17) such as a capacitance sensor
8) and a resist tank (19) through which the resist can be supplied onto the semiconductor wafer.

Here, the cup (5) is supported on, for example, an Al square plate-like base (20) by screwing or the like. Similarly, the spin motor (4) is also screw-fastened or the like by an Al circular plate-like motor mounting plate. (2
It is fixedly supported by the base (20) via 1). The motor mounting plate (21) corresponds to the "member in contact with the motor" in claim 1 and the "first member" in claim 2. Further, the base (20) corresponds to the “second member” of the second aspect. The motor mounting plate (21) is supplied with constant temperature water from the second temperature controller (22) by using, for example, urethane resin or rubber pipes (23a,
The circulation temperature can be controlled via 23b), and forms means for controlling heat transmitted through the drive shaft of the spin motor (4), that is, the output shaft (3), and radiant heat from the spin motor (4). That is, as shown in FIG. 2, the motor mounting plate (2) supported by the base (20) and fixing the spin motor (4).
1) Insert a pipe (2) into the hole (30)
The motor mounting plate (21) can be controlled to a desired temperature by circulating constant-temperature water through 3a, 23b), whereby the radiant heat from the spin motor can be controlled. Further, between the output shaft (3) and the motor mounting plate (21), a heat conductive material such as sintering can be controlled by controlling the temperature of the motor mounting plate (21) to control the heat transmitted through the output shaft (3). A gold cylindrical bearing (31) is provided.

The operation and setting of the semiconductor wafer processing apparatus having the above configuration are controlled by a control unit (not shown).

Next, a method of applying a resist on a semiconductor wafer by the above-described semiconductor wafer processing apparatus will be described.

A substrate to be processed, for example, a semiconductor wafer (1) is transferred onto the wafer chuck (2) by a transfer mechanism (not shown), for example, a belt, and the center of the semiconductor wafer (1) is aligned with the center of the wafer chuck (2). (2)
Place on top. This centering may be performed in advance by a mechanism (not shown) outside the cup (5). Then, the placed semiconductor wafer (1) is sucked and held by a wafer chuck (2) by a vacuum mechanism (not shown). At this time, in order to facilitate the transfer of the semiconductor wafer (1), the cup (5) may be lowered beforehand with respect to the support (20) supported by the cup (5), and may be raised after being held.

A resist is dropped from the resist dropping nozzle (9) to the center of the held semiconductor wafer (1). The resist is supplied from the resist tank (19) to the nozzle (9) through the pipe (13a) by the action of the pump (16) and the pump drive mechanism (15). The supplied resist is provided to the pump (16). There is no backflow by the check valve (14) provided. Here, a tank (18) having a liquid level sensor (17) is provided between the pump (16) and the resist tank (19) via pipes (13b, 23c).
The remaining amount of the resist is detected by detecting the amount of the resist inside. Since the remaining amount of resist is detected in this manner, when the remaining amount of resist is reduced, bubbles are mixed in the resist, thereby preventing the occurrence of a large number of defective products and a drastic reduction in the yield. The case where the desired amount of the resist is not obtained and the desired film thickness of the resist is not obtained or the case where the uniformity of the film thickness cannot be obtained can be prevented, and the productivity is improved. In addition, it is possible to prevent the semiconductor wafer (1), which could not be processed at all because the remaining amount of the resist completely disappears, from being erroneously sent to the next step. In addition, since the replacement work of the register tank (19) can be incorporated in the work process in advance, there is an effect that the work efficiency can be improved.

The means for detecting the remaining amount of the resist may be calculated from the number of operations of the pump drive mechanism (15) and the capacity of the pump (16), and the weight of the resist tank (19) is detected by a weight sensor such as a strain sensor. Then, the remaining amount of the resist may be detected.

Here, when this resist is supplied to the resist dropping nozzle (9), the resist in the nozzle (9) is supplied to the heat exchanger (10) by the pipes (11a, 11b) and the first temperature controller (12). The temperature of the circulated constant temperature water is a desired temperature, for example, about 20 ° C. to 30 ° C. In this way, by controlling the temperature of the dropped resist by, for example, heat exchange of a double tube structure, the resist can be applied to the surface of the semiconductor wafer (1) in a state in which the temperature of the resist has not changed, and the thickness of the film can be reduced. Unevenness and unevenness between lots can be prevented, and the yield can be improved.

At this time, the spin motor (4) has already been rotated at a desired rotational speed, for example, about 4000 to 6000 rpm, and a desired acceleration, for example, 10,000.
It rotates at ~ 50000rpm / sec. During this rotation, heat is generated from the spin motor (4), and this heat is transmitted through the output shaft (3) or directly emitted from the spin motor (4) as radiant heat, and is transferred to the semiconductor wafer (1) and the wafer chuck (2). Although it has an effect, pipes (23a, 23a) are inserted into holes (30) inside the motor mounting plate (21) that firmly supports the top surface of the spin motor (4).
The temperature of the motor mounting plate (21) is controlled by circulating constant temperature water from the second temperature controller (22) via b). Thus, the heat transmitted to the drive shaft of the spin motor (4), that is, the output shaft (3) can be controlled by the motor mounting plate (21) via the bearing (31), and the radiant heat from the spin motor (4) can also be controlled. It can be controlled with the motor mounting plate (21). Therefore, the output shaft (3) of the spin motor (4)
In order to prevent the temperature of the wafer chuck (2) and the semiconductor wafer (1) from being uneven, the uniformity of the resist film thickness is improved, and The yield can be improved by the uniformity.

Next, a resist is dropped on the semiconductor wafer (1) and diffused on the surface of the semiconductor wafer (1) by centrifugal force. The semiconductor wafer (1) is further rotated to dry the diffused resist. During such processing, the inside of the cup (5) is exhausted by an exhaust mechanism (not shown) through the exhaust pipe (8) according to a program preset in a control unit (not shown). Further, the resist scattered by the rotation of the semiconductor wafer (1) forms an angle A on the inner side of the cup (5), that is, in the vicinity of the intersection with the extended surface of the surface of the semiconductor wafer (1).
(A {90}) prevents the semiconductor wafer (1) from rebounding from the surface provided by being inclined and adheres to the peripheral portion and falls. Then, the used resist is accommodated in the drain box (7) for accommodating the used resist via the scattered resist discharge pipes (6a, 6b). Here, since the discharge pipe (6b) connected to the discharge pipe (6a) can move up and down in the direction of the arrow, the drain box (7) can be easily moved in the horizontal direction with the discharge pipe (6b) raised. , The drain box (7) can be replaced in a short time, and the operation efficiency of the apparatus is improved. The replacement of the drain box (7) automatically raises the discharge pipe (6b) by detecting the used resist amount in the drain box (7) or detecting the weight of the drain box (7). It may be made to be replaced.

Then, the processing is completed by unloading the processed semiconductor wafer by a transfer mechanism (not shown).

Further, in the above embodiment, the means for controlling the heat transmitted through the drive shaft of the motor and the radiant heat from the motor are described by controlling the temperature of the plate on which the motor is mounted with constant temperature water. It is only necessary to control the heat generated, and the present invention is not limited to the above embodiment.

In addition, in the above embodiment, the temperature control of the resist was described by heat exchange using the constant temperature water of the nozzle. However, it is sufficient that the temperature of the resist immediately before dropping can be controlled to a desired temperature. Needless to say, the temperature may be controlled by the above method.

As described above, according to this embodiment, when the semiconductor wafer on the wafer chuck is rotated by the spin motor, and the resist or the like is dropped on the semiconductor wafer for processing, the heat transmitted through the drive shaft of the spin motor and the spin motor are used. By controlling the radiant heat of the motor, that is, by adopting a structure for controlling the temperature of the motor mounting plate, uniformity of processing such as uniformity of the resist film thickness can be realized.

〔The invention's effect〕

As described above, according to the present invention, processing such as uniformity of the resist film thickness and uniformity can be improved, and the yield can be improved.

[Brief description of the drawings]

FIG. 1 is a view for explaining the components of an embodiment of the apparatus of the present invention, and FIG. 2 is a view for explaining the spin motor and the motor mounting plate of FIG. In the drawing, 1 ... a semiconductor wafer, 2 ... a wafer chuck 3 ... an output shaft, 4 ... a spin motor 21 ... a motor mounting plate, 22 ... a second temperature controller, 30 ... a hole, 31 ... bearing

Claims (4)

(57) [Claims] 1. A liquid processing apparatus for supplying and processing a resist liquid on a processing surface of a rotating object to be processed, wherein first temperature control means for adjusting the temperature of the resist liquid supplied to the processing surface of the object to be processed. A holding member configured to hold the object to be processed and rotatable based on rotation of an output shaft of the motor; and a member configured to be capable of projecting the output shaft of the motor and contacting the motor. Second temperature control means for adjusting the temperature of an area of the member that comes into contact with the motor, wherein the member is configured to thermally separate the motor side and the holding body side. Liquid treatment equipment. 2. A liquid processing apparatus for supplying and processing a resist liquid on a processing surface of a rotating object to be processed, wherein first temperature control means for adjusting the temperature of the resist liquid supplied to the processing surface of the object to be processed. A holding member configured to hold the object to be processed and to be rotatable based on rotation of an output shaft of a motor; provided at a position below the holding member so that the output shaft of the motor can protrude. A first member, a second temperature adjusting means for adjusting the temperature of the first member, and a heat member that is provided in contact with the first member and heats the holder together with the first member on the motor side. And a second member for partitioning the liquid. 3. The liquid processing apparatus according to claim 1, wherein said motor is attached to said member or said first member. 4. The liquid processing apparatus according to claim 1, wherein the second temperature control means has a structure for circulating constant temperature water inside the member or the first member.