JPH0513533B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a resist developing device, and more particularly, to a resist developing device for developing a resist layer attached to an object to be developed such as a semiconductor wafer, a semiconductor mask, or an optical disk. .

(Prior Art) Conventionally, a developing device for developing a resist layer on a semiconductor wafer is disclosed in Japanese Patent Laid-Open No. 56-98826, and as shown in FIG. a nozzle N, a developer container C, and a pump P that supplies the developer to the nozzle N.
The resist is developed by injecting a developer from the nozzle N.Recently, as resists have become more sensitive, the current conditions for the resists, particularly temperature requirements, have become more important. , a temperature control section for adjusting the temperature of the developer between the developer container C and the nozzle N;
A thermometer TE is provided to control the temperature and flow rate of the developer by providing a TC and a valve (FV) for adjusting the amount of the developer. and the nozzle N and the wafer W held opposite to the nozzle N.
A shutter S that freely moves forward and backward is provided between the nozzle N and the wafer W, and when the temperature of the developer has not reached the set temperature, the shutter S is advanced between the nozzle N and the wafer W, and the shutter S is moved between the nozzle N and the wafer W. When the developing solution from N is received and the set temperature is reached, the shutter S is moved back so that the developing solution can be sprayed onto the wafer W, and the temperature of the developing solution acting on the wafer W can be limited to the set temperature. That's what I do.

In FIG. 6, _M1 is a driving motor for the shutter S, and CT is its controller. Further, _M2 is a motor that rotates the wafer W.

(Problems to be Solved by the Invention) When controlling the temperature of the developer as described above,
Since most of the developer is volatile, it will partially evaporate when it is injected from the nozzle N, cooling the inside of the developing chamber and lowering the saturation pressure. Even if the temperature is accurately controlled, the temperature inside the developing chamber cannot be accurately maintained at a constant temperature.

The resist developing device is usually installed in a controlled room, but since this controlled room also includes various control devices, the temperature is controlled by taking into consideration the amount of heat radiated from each of these devices. There is a need,
For this reason, it is difficult to control the room temperature with high precision, resulting in variations of, for example, ±1.0°C.Also, the outer surface of the wall of the developing chamber is in contact with the air in the control room; Since the heat transfer coefficient is much smaller than the heat transfer coefficient on the inner surface of the wall in contact with the developer and the time for one development is short, the temperature of the developing chamber to which heat is supplied from the regulating chamber is the temperature of the regulating chamber. It is not controlled by. Therefore, from the above, the temperature inside the developing chamber tends to decrease due to the evaporation of the developer, and it becomes impossible to maintain the temperature at a constant temperature.

Also, JP-A-57-166032 and JP-A-55-2213
In the above publication, it has been proposed that a heating source using a heater is attached to the developing tank that defines the source image chamber, and the temperature inside the developing chamber is controlled by heating, but heating by the heater alone is not optimal in the first place. It is not possible to deal with cases where the developing temperature is lower than the external ambient temperature, and even if the optimum developing temperature is higher than the external ambient temperature, controlling the heater on/off alone will result in overheating. There is a problem in that when the indoor temperature rises above the optimum value, it is impossible to forcefully lower the temperature, and it is extremely difficult to control the temperature with high precision within ± a few tenths of a degree.

(Means for Solving the Problems) The present invention solves the above-mentioned conventional problems, and makes it possible to arbitrarily set the temperature inside the developing chamber and to maintain it accurately at the set temperature.
As shown in FIG. 1, a developer tank 1 is equipped with a holding means for holding an object W to be developed, such as a semiconductor wafer, and a nozzle 2 for discharging a developer onto the object W held by this holding means. In the resist developing device, the developing tank 1 is sealed to isolate the internal developing chamber 10 from the outside with a door 21 closing the entrance 20 for the object W to be developed which opens on the wall surface of the developing tank 1. A heat exchange chamber 14 facing the developer chamber 10 is formed on the wall surface of the developer tank 1, and a heater 71 is used as a heat source, and an evaporator 72 of a freezing device is used as a cooling source, and arbitrary settings can be made. A constant temperature heat medium generation device 7 that generates a constant temperature heat medium is formed, and this constant temperature heat medium generation device 7 is connected to the heat exchange chamber 14 via piping 76, 77. This is characterized in that a heat medium pump 75 is provided between the constant temperature heat medium generator 7 and the heat exchange chamber 14 to circulate the constant temperature heat medium.

(Function) As described above, since the developer tank 1 is made into a closed structure with the discharge type using the nozzle 2, the inside of the developer chamber 10 is brought to the saturation pressure of the developer within a short time after the developer is released. This makes it possible to suppress the temperature drop due to evaporation of the developer.
Moreover, in addition to the heater 71 as a heating source, a constant-temperature heating medium generator 7 equipped with an evaporator 72 as a cooling source is separately formed, and a heat exchange chamber 14 is provided with a constant-temperature heating medium at an arbitrary set temperature on the wall surface of the developer tank 1. Therefore, the temperature inside the developing chamber 10 can be raised or lowered relative to the external ambient temperature, and it is possible to cope with cases where the optimum developing temperature is lower than the external ambient temperature. Since cooling is used in combination, overheating can be corrected by cooling, and highly accurate temperature control can be performed near the optimum developing temperature. Furthermore, since the constant temperature heating medium is circulated by the heating medium pump 75 and new heating medium is constantly supplied to the heat exchange chamber 14, the temperature of the chamber 14 itself can be maintained uniformly, and temperature fluctuations within the developing chamber 10 can also be suppressed. It is possible to do so. In this way, these factors work together to maintain the temperature inside the developing chamber 10 as a whole at any desired set temperature, regardless of the external ambient temperature.
It is possible to maintain a constant temperature controlled with high precision of a few tenths of a degree, and the phenomenon of the object W can be maintained at a constant temperature of several tenths of a degree.
This means that it can be repeated multiple times without any variation.

(Example) In FIG. 1, 1 is a developer tank, and this developer tank 1 consists of a body 11 with a double wall structure, a bottom wall 12, and a lid body 13, and a developing chamber 10 is formed inside. In addition, due to the double wall structure of the fuselage 11,
A heat exchange chamber 14 surrounding the developing chamber 10 is formed.

Further, a support cylinder 15 is provided upright on the bottom wall 12, and a rotary shaft 17 having a chuck 16 at an upper end for fixedly holding a semiconductor wafer W as a developing object, for example, is rotatably supported inside the support cylinder 15. The lid 13 also has the chuck 16.
The nozzle 2 is arranged to face the wafer W held by the wafer W.

This nozzle 2 is connected to a developer container 3 via a liquid feed pipe 6 in which a liquid feed pump 4 and a temperature control section 5 are interposed, and the temperature-adjusted developer is supplied from the container 3 to the nozzle 2. The developing solution is ejected from the nozzle 2 onto the wafer W, for example, by spraying.

Although the temperature control unit 5 is not particularly necessary, it controls the temperature of the developer sprayed from the nozzle 2 onto the wafer W to a constant temperature, and can be controlled by, for example, constant temperature water.

Next, the constant temperature heat medium generator 7 will be explained.
In this embodiment, constant temperature water is used as the constant temperature heating medium.

This generator 7 includes a constant temperature bath 70 with a heat insulating structure.
In addition, a heater 71 and an evaporator 72 of the refrigeration system are installed inside, and a take-out pipe 74 with a strainer 73 is arranged near the bottom of the constant temperature bath 70, and a heat medium pump 75 and liquid supply piping are installed. 76 to the liquid inlet 18 provided at the bottom of the heat exchange chamber 14, and the heat exchange chamber 1
A liquid drain port 19 provided at the upper part of 4 is connected to the constant temperature bath 70 via a liquid return pipe 77.

The heater 71 and evaporator 72 installed in the constant temperature bath 70 are operated by detecting the indoor temperature of the developing chamber 10 or the water temperature (thermal medium temperature) in the heat exchange chamber 14, and adjusting settings arbitrarily set in advance. It is controlled by a controller 8 that performs a comparison with the temperature, and by controlling the operation of the heater 71 and evaporator 72, it is possible to form constant temperature water (constant temperature heating medium) with an error of ±0.1 degrees Celsius from 5 degrees Celsius to 40 degrees Celsius. It is.

Further, a condenser 78 in the refrigeration system corresponding to the evaporator 72 is provided in the condensing unit 9 together with the compressor.
The operation of the compressor is controlled by starting and stopping the compressor or by controlling the capacity.

In FIG. 1, reference numeral 20 denotes a wafer entrance/exit provided in the body 11 of the developer tank 1, and a door 21 is attached to this entrance/exit 20 so that it can be opened and closed freely.

Further, reference numeral 22 denotes a fan attached to the lid 13. By providing this fan 22, the interior of the developing chamber 10 can be quickly saturated, and the inner wall of the body constituting the heat exchange chamber 14 can be easily saturated. Heat transfer coefficient can be improved.

Further, the developer injected from the nozzle 2 is, for example, about 50% of isobutyl alcohol and ethanol.
A mixture of 50% and 50% is used, and
The developing temperature (° C.) and resist sensitivity (μc/cm ² ) of this developer change as shown in FIG. In addition, in FIG. 5, the vertical axis is expressed on a logarithmic scale.

In the above configuration, when developing the semiconductor wafer W, first, the operation of the constant temperature heating medium generator 7 is preceded, and the constant temperature heating medium circulating between the constant temperature bath 70 and the heat exchange chamber 14 is set in advance. It controls the temperature to the set temperature.

This set temperature can be arbitrarily set using the input device of the controller 8, and can be accurately controlled to the arbitrarily selected set temperature. It can be retained.

After the temperature of the constant-temperature heating medium circulating through the generator 7 and the heat exchange chamber 14 reaches the set temperature, the semiconductor wafer W held in the chuck 16 is rotated by the rotation shaft 17. At the same time, the developer is injected from the nozzle 2.

Since the developing chamber 10 can be maintained at a constant temperature in advance by circulating a constant temperature heating medium, reliable development is possible from the first semiconductor wafer W without using a dummy at the beginning of development. be.

Further, the temperature of the developing chamber 10 tends to change due to the injection of the developer from the nozzle 2, but since the developing chamber 10 is sealed, the saturation pressure of the developer is adjusted at the same time as the developer is jetted. The wall of the developer tank 1 is formed by a heat exchange chamber 14, and the heat exchange chamber 14 allows the intrusion of heat from the outside to be ignored, so there is no temperature change in the developer chamber 10, and the temperature can be controlled with high precision. Therefore,
It is possible to develop each of the first to Nth wafers W at a constant temperature with high precision, that is, without variations in sensitivity.

In the embodiment shown in FIG. 1, only the body 11 has a double wall structure so that the heat exchange chamber 14 is formed only at the side circumference of the developer tank 1. However, in the embodiment shown in FIG. For example, by using a lid 13a with a double wall structure instead of the lid 13, an upper heat exchange chamber 14a is formed,
Further, by communicating this upper heat exchange chamber 14a with a side heat exchange chamber 14b having a double wall structure of the body 11, a heat exchange chamber 14 is formed between the upper part and the side circumference of the developer tank 1. You can do it like this.

Furthermore, as shown by the imaginary line in FIG. 2, the bottom wall 12
For example, by forming a double wall structure to form a lower heat exchange chamber 14c, and by connecting the lower heat exchange chamber 14c to the side peripheral heat exchange chamber 14b, the upper and lower parts of the developer tank 1 can be separated. A heat exchange chamber 14 may also be formed on the side circumference, that is, on the entire outer wall of the developer tank 1.

The above-mentioned upper and lower heat exchange chambers 14
a, 14c may be configured in combination with the side circumferential heat exchange chamber 14b as described above, but they may be configured independently, that is, in the upper heat exchange chamber 14, without using the side circumferential exchange chamber 14b.
The heat exchange chamber 14 may be configured with only the heat exchange chamber 14a or the lower heat exchange chamber 14c, or the upper and lower heat exchange chambers 14a, 14 may be configured without using the side heat exchange chamber 14b.
The heat exchange chamber 14 may be configured by combining both of c. Further, either one of the upper and lower heat exchange chambers 14a and 14c may be combined with the side peripheral heat exchange chamber 14b. In addition, when combining the upper and lower heat exchange chambers 14a, 14c without using the side peripheral chamber 14b, these chambers 14a,
14c is connected with a connecting pipe or the like. Also,
When only one of the chambers 14a, 14b, and 14c described above is used alone, it goes without saying that the liquid sending pipe 76 and the liquid returning pipe 77 are connected to that one chamber. .

Furthermore, in the embodiments shown in FIGS. 1 and 2, the body 11 of the developer tank 1 has a double wall structure, so that
Although the heat exchange chamber 14 was formed, as shown in FIG. The heat exchange chamber 14 may be formed by adhering to the wall surface using paste solder or adhesive in a heat conductive manner.

In this case, it is preferable that the cross-sectional shape of the pipe 50 is, for example, a flat ellipse to increase the contact area with the wall surface. Further, it is preferable that the winding pitch of the pipe 50 is tight.

Further, in the embodiment shown in FIG. 3, the pipe 50 is tightly wound, but as shown in FIG. .

In the embodiment shown in FIG. 4, the framed frame 1
A developing tank 1 is supported on the upper part of 00, and a constant temperature heating medium generator 7 is housed below. Further, the liquid return pipe 77 constitutes a double pipe 40 together with the developer liquid feed pipe 6, and the temperature of the liquid feed pipe 6 is also controlled using this liquid return pipe 77. . Furthermore, a part 6a of the liquid feeding pipe 6 extending from the liquid feeding pump 4 is disposed inside the constant temperature heat medium generator 7, and together with the double pipe 40 described above, constitutes the temperature control section 5 for the developer. There is.

In FIG. 4, 61 is a control valve that controls the supply and stop of the developer, 62 is a filter, 200 is a wafer cassette placed on a stand 201 provided on the upper surface of the frame 100, and M is the developer tank. This motor drives a rotating shaft 17 of a chuck 16 installed in the motor 1, and is interlocked with the rotating shaft 17 by a belt transmission means 101.

(Effects of the Invention) As described above, in the present invention, in the case of the discharge type using the nozzle 2, the developer tank 1 is made into a sealed structure, the heat exchange chamber 14 is formed on the wall surface of the developer tank 1, and in addition to the heater 71 which is the heating source, the refrigerator is used as the cooling source. The developing chamber is equipped with an evaporator 72 of the machine, a separate constant-temperature heat medium generator 7 for generating a constant-temperature heat medium at an arbitrary set temperature, and a configuration in which the constant-temperature heat medium is circulated by a heat medium pump 75. An arbitrary set temperature that is aimed at a temperature within 10 degrees Celsius, regardless of the external ambient temperature, ± a few tenths of a degree.
It is possible to maintain a constant temperature that is controlled with high precision, and it is possible to develop the object W such as a semiconductor wafer without variation from the first time to multiple times, improving the product yield. It can be done.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram showing a first embodiment of the developing device of the present invention, FIG. 2 is an explanatory diagram of only the developing tank showing the second embodiment, and FIG. 3 is a schematic explanatory diagram showing the third embodiment.
FIG. 4 is a schematic explanatory diagram showing the fourth embodiment, FIG. 5 is a characteristic diagram of the development temperature of the developer and resist sensitivity change, and FIG. 6 is a schematic explanatory diagram showing the conventional example. 1... Developer tank, 2... Nozzle, 7... Constant temperature heating medium generator, 10... Development chamber, 14... Heat exchange chamber, 76, 77... Piping, 20... Entrance/exit,
21...door, 71...heater, 72...evaporator,
75... Heat medium pump, W... Object to be developed.

Claims (1)

[Claims] 1 A resist developing device in which a developing tank 1 is provided with a holding means for a developing object W and a nozzle 2 for discharging a developer onto the developing object W held by the holding means, the developing tank 1 is formed into an airtight structure that isolates the internal developing chamber 10 from the outside with the entrance 20 for the object to be developed W opened on the wall of the developing tank 1 closed with a door 21. ,
A constant-temperature heat medium generation device that forms a heat exchange chamber 14 facing the developing chamber 10, uses a heater 71 as a heat source, and uses an evaporator 72 of a freezing device as a cooling source to generate a constant-temperature heat medium at an arbitrary set temperature. The constant temperature heat medium generator 7 is connected to the heat exchange chamber 14 via piping 76, 77, and the heat is connected between the heat exchange chamber 14 and the constant temperature heat medium generator 7. A resist developing device characterized in that a heat medium pump 75 for circulating a constant temperature heat medium is provided in the exchange chamber 14.