JP2828682B2 - Development method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a developing method.

2. Description of the Related Art Conventionally, a semiconductor element manufacturing process includes a resist coating process, an exposure process, and a developing process. Conventionally, this developing step is performed as follows. That is, the development of a resist film formed by adding a quinonediazide-based material as a photosensitizer to a phenol / novolak resin material is performed by using an alkali-based developer mainly containing tramethylammonium hydroxide as a semiconductor wafer substrate (hereinafter, referred to as a wafer). (Abbreviated as "abbreviated") is developed by spin coating on the surface. In this developing method, a mostly liquid developing substance is supplied onto a surface of a wafer by a nozzle. For example, as shown in FIG. 5, the developer (2) is held on the upper surface of the wafer (1) by surface tension and interfacial tension, and the wafer (1) is rotated at a low speed so that the developer (2) does not drop. Developing method, or immersing the wafer (1) in the developing solution (2), and further spraying the developing solution on the surface of the wafer (1) to accumulate the developing solution (2) on the surface of the wafer (1) And developing. In any case, a liquid developing substance is added on the wafer (1). This method is disclosed in Japanese Patent Application Laid-Open Nos. 56-33834 and 57-122.
No. 8, JP-A-57-32445, JP-A-57-166032, JP-A
57-192955, JP-A-57-208134, JP-A-58-4147
No., JP-A-58-52645, JP-A-59-46649, JP-A-59-46649
No. -50440, JP-A-60-126651, JP-A-61-147256
And JP-A-62-239532.

(Problems to be Solved by the Invention) Further, Japanese Utility Model Application Laid-Open No. 58-98640 for developing using a liquid and a gas, and Japanese Patent Application Laid-Open No. Sho 58-98640 for performing a plasma discharge of a resist formed on a substrate and performing dry development. 58-10
3045 etc. However, the conventional wafer developing method uses a liquid developing substance (developer) to prepare a wafer (1).
Because it is a method of developing the resist film attached to the
When fixing the resist film (3) on the wafer (1), the developing solution (2) cannot be quickly removed from the wafer, and excessive development, for example, developing (dissolving) even the resist film on an unexposed portion of the wafer. Resulting in. This excessive development has been a problem particularly in forming a fine circuit pattern on a wafer such as recent 1M, 4M, 16M, and 64M ultra-high-density ICs, and improvement has been demanded.

That is, as shown in FIG. 5 (a), the resist film (3) added to the wafer (1) is first developed with the supplied developer (2), and then as shown in FIG. 5 (b). In order to remove the developing solution (2) from the wafer (1), the developing solution (2) is shaken off by rotating the wafer (1) at a high speed by a rotating mechanism (not shown). However, a small amount of the developing solution (2) remains in a part of the wafer (1), and the remaining developing solution (2) develops a part of the wafer (1).
In this development, the resist coating (3) up to the unexposed portion (4) of the wafer (1) is dissolved. That is, since the development is excessively performed compared to the predetermined development processing, it is difficult to form a fine circuit pattern on the wafer (1).

SUMMARY OF THE INVENTION It is an object of the present invention to provide a developing method for preventing an object to be processed from being excessively developed.

[Configuration of the invention]

(Means for Solving the Problems) In order to solve the above problems, the present invention firstly comprises a step of loading an object to be processed having a resist film with an exposure pattern formed therein into a processing chamber; Depressurizing, supplying a developing gas into the processing chamber to develop an exposure pattern of the resist film on the object to be processed, and stopping the supply of the developing gas into the processing chamber after a predetermined developing time has elapsed. Introducing air into the chamber and exhausting the processing chamber, then supplying a cleaning liquid to the processing object in the processing chamber to wash the processing object, and then drying the processing object, and opening the processing chamber to perform the processing. And a step of removing the body.

Secondly, a step of loading an object to be processed having a resist film on which an exposure pattern is formed, a step of depressurizing the processing chamber, and a step of supplying a developing gas into the processing chamber to form a resist film on the object to be processed. Step of developing the exposure pattern of, after a predetermined development time, supply of the developing gas into the processing chamber is stopped, an inert gas is introduced into the processing chamber, the processing chamber is purged, and the processing chamber is exhausted. Next, a step of supplying a cleaning liquid to the object in the processing chamber to clean the object, and thereafter drying the object, and a step of opening the processing chamber and taking out the object are provided. To provide a developing method.

Thirdly, there is provided a developing method according to the first or second aspect, further comprising a step of detecting an end point of development.

Fourthly, in the first to third inventions, there is provided the developing method, wherein the developing gas contains an alkali element compound.

Fifthly, in the first to fourth aspects of the present invention, there is provided a developing method, wherein the object to be processed is heated or cooled according to a type of a developing gas.

(Effects) According to the first aspect of the present invention, in the development with the developing gas, after a predetermined developing time is over, the gas supply is stopped, the gas is introduced into the atmosphere, and the processing chamber is evacuated. Can be removed. That is, in the present invention, the object to be processed is developed with the developing gas. In the developing gas, the developing substance floats in an independent molecular state, and the independent molecule adheres to the object and develops. If the gas adheres later, over-development may be caused.However, by introducing the atmosphere into the processing chamber after the development, the molecules can be easily separated from the object to be processed, and exhausted together with the gas. Thereby, the molecule can be quickly discharged to the outside. Therefore, the developing gas can be quickly removed from the object. In addition, since the object to be processed is washed by supplying a cleaning liquid into the processing chamber subsequent to such an operation and then dried, the remaining developing gas particles and the like can be quickly removed. For this reason, it is possible to reliably prevent excessive development in the development using the developing gas,
A highly accurate circuit pattern can be formed. Also,
As described above, since the cleaning and drying with the processing liquid are performed in the same processing chamber, when the substrate to be processed is unloaded from the processing chamber,
Since it is in a clean state, it is possible to effectively prevent particles from adhering during the transfer of the object to be processed, and to remarkably increase the throughput.

According to the second aspect, an inert gas is introduced into the processing chamber instead of introducing the atmosphere of the first aspect.
In addition to the effects of the invention, the development gas is prevented from being released to the atmosphere, and without contact with the atmosphere,
Since the object to be processed can be washed and dried, formation of an unnecessary oxide on the object to be processed can be prevented.

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

The development process is a process of removing a resist film on an exposed portion of an exposed semiconductor wafer (hereinafter, abbreviated as a wafer). In this step, the wafer exposure step and the development step are arranged adjacent to each other.

This developing step is performed by a dry developing device that develops a wafer in a developing chamber filled with a developing gas.

As shown in FIG. 1, the configuration of the dry developing device is as follows.
The exposed wafer (5) is shielded from the atmosphere and is provided in an airtight manner. The hermetically sealed chamber is filled with a developing gas for development, and the exposed wafer (5) is exposed to the developing chamber (6). , For example, a carry-in handling arm (7), and a carry-out unit, such as a carry-out handling arm (7), for taking out the wafer (5) developed in the development processing chamber (6) from the development processing chamber (6). And consists of

The development processing chamber (6) is provided in an airtight manner. That is, a cylindrical upper cup whose upper surface is closed by a plate-like material, for example, a 400 mm diameter x 150 mm x 2 mm thick stainless steel upper cup (6a), and a cylindrical upper cup whose bottom is closed by a plate-like material A lower cup, for example, 400 mm in diameter x 150 mm in height x 2 mm in thickness, and a stainless steel lower cup (6b) is provided airtightly via a sealing member, for example, an O-ring (6c) made of neoprene having an outer diameter of 405 mm x an inner diameter of 395 mm x a height of 6 mm. ing.

The upper cup (6a) is connected to an elevating mechanism (8) so as to move up and down. That is, the upper cup (6a) and the lower cup (6b) are aligned to form an airtight chamber (8), in which a wafer (5) is placed at a predetermined position.
For example, the upper cup (6a) is separated from the lower cup (6b) fixed to check whether the upper surface of the spinner (9) has been reached, or when performing maintenance for a trouble that has occurred in the airtight chamber (8). An elevating mechanism (8) is provided to open the closed room (8).

A nozzle (10) for introducing a developing gas, for example, an alkali element compound gas, into the hermetic chamber (8) is provided at the center of the upper cup (6a) so that a discharge port faces a surface of a spinner (9) described later. . At the tip of the nozzle (10), a diffusion plate (11) to be filled with a developing gas containing the alkaline element compound dispersed and introduced around the airtight chamber (8) is filled with a spinner (8) surface. They are provided so as to face each other.

At the opposite end from the nozzle (10), a supply system (12) for introducing the developing gas and the atmosphere into the airtight chamber (8) is provided. The supply system (12) is piped so that the nozzle (10) communicates with the developing gas source (12a) containing an alkali element compound. An air supply system (12a) for sending air into the airtight chamber (8) is provided in the middle of the pipe. A switching valve (12c) is provided so that the air supply system (12a) and the developing gas source (12a) can be selected.

That is, the developing chamber containing the alkali element compound is introduced into the hermetic chamber (8) when the wafer (5) is developed in the hermetic chamber (8). Further, when the developed wafer (5) is fixed, the switching valve (12c) is switched to the air supply system (12a) so that the atmosphere is introduced into the airtight chamber (8).

The upper surface of the upper cup (8a) forming the hermetic chamber (8) is formed by developing the wafer (5) and then dissolving the molecules of the alkali-based compound gas attached to the wafer (5) and the dissolved gas. Cleaning liquid to remove resist (13)
A cleaning nozzle (14) for discharging the ink is provided on the upper cup (6a).

The cleaning nozzle (14) applies the cleaning liquid (13) to the wafer (5) based on a command from a controller (not shown), for example, a CPU.
An on-off valve (15) for discharging the liquid to the air is provided.

At the center of the lower cup (6b) forming the airtight chamber (8), there is provided a spinner (9) mounted on and supported by the transferred wafer (5). A rotating mechanism, for example, a motor (16), is provided below the spinner (9) to shake off the cleaning liquid (13) together with the dissolved resist when cleaning the wafer (5).

A discharge system (17) for discharging a cleaning liquid (13) to the wafer (5) and discharging the cleaned liquid to the lower cup (6b).
Are provided perpendicular to the bottom surface.

The lower cup (6b) is provided with an on-off valve (17a) for exhausting the gas in the airtight chamber (8) to the outside and then making the airtight chamber (8) airtight.

The carry-in handling arm (7) is provided in a load lock chamber (18) provided on a side surface of the airtight chamber (8), and the wafer () exposed from the exposure device (19) side to the airtight chamber (8) side. 5) can be transported.

Further, the carry-in handling arm (7) is also used as a carry-out handling arm (7) for taking out the developed wafer (5) from the airtight chamber (8) to the outside.

 Next, the operation will be described.

First, a command signal is transmitted from the exposure device (19) side to the control section on the dry developing device side to develop the exposed wafer (5). Upon receiving this signal, the dry developing device operates in accordance with the program stored in advance to set the upper cup (6
Lower a) to match the lower cup (6b) fixed below this upper cup (6a). That is, an airtight chamber (8) for dry developing the wafer (5) is formed. The wafer (5) is transferred from the exposure apparatus (19) into the airtight chamber (8) by the carry-in handling arm (7) in the load lock chamber (18) provided between the airtight chamber (8) and the exposure apparatus. Replace. That is, the wafer (5) is supported on the upper surface of the spinner (9) provided at the center in the airtight chamber (8).
In this state, the wafer (5) transferred into the hermetic chamber (8) is subjected to dry development processing.

That is, the dry development process is performed in the hermetic chamber, for example, 25
The volume of the airtight chamber (8) is reduced to a predetermined negative pressure, for example, about 0.5 Torr.

When a pressure sensor (not shown) provided in the hermetic chamber (8) senses that a predetermined negative pressure value has been reached, this signal switches the switching valve (12c) to the developing gas source (12a) side.

A developing gas containing an alkali element compound, for example, a gas amount of 25 is introduced from the side of the developing gas source (12a) into the hermetic chamber (8) at a flow rate of, for example, 2 / s, and is filled. At this time, it is desirable that the exhaust pump is appropriately operated. The countless molecules P of the filled developing gas are shown in FIG.
And, as shown in FIG. 2 (b), it adheres to those which come into contact with the surface of the wafer (5) supported by the spinner (9). The rotation speed of the motor (16) at this time can be appropriately selected. Of course, it may be stopped. Further, the wafer may be heated or cooled to an optimum temperature according to the type of the developing gas. Further, a development end point detection may be provided to automatically stop. The attached numerous molecules P react with the exposed resist film (5a) and develop (dissolve). This solution amount is dissolved by the same amount as the molecular P amount. On the dissolved resist film (5a), molecules P of the developing gas are adhered again as shown in FIG. 2 (c). The attached molecule P dissolves the dissolved resist film (5a) further deeply. A gas such as an inert gas may be purged simultaneously with the detection of the development end point to terminate the development processing.
After the development, the processed wafer is unloaded via the load lock. Thus, the above-mentioned exposed resist film (5a) is subjected to predetermined development by repeating the above-described method.

Next, as shown in FIG. 2D, when a predetermined developing time has elapsed, the supply of the developing gas is stopped, and the developing gas in the hermetic chamber (8) is removed. Switch the switching valve (12c) to the atmosphere piping side to supply the atmosphere. Then, the air is introduced into the airtight chamber (8), and the developing gas is exhausted from the exhaust system (17). In this case, if the development processing space for the wafer is set to a volume necessary to accommodate the wafer, the throughput is improved. Since the exhaust gas removes the developing gas from the hermetic chamber (8), the phenomenon of adhesion of molecules P of the developing gas to the surface of the wafer (5) disappears, and the developing process of the wafer (5) is stopped. If a spare chamber is provided on the loader side or unloader side of the development processing chamber or in common to improve the throughput, the throughput is further improved.

Next, as shown in FIG. 2 (e), the molecules P attached to the unexposed portions of the wafer (5) and the dissolved resist film (5a) are removed with a cleaning liquid (13).

Next, as shown in FIG. 2 (f), the wafer (5) cleaned with the cleaning liquid (13) is rotated at a high speed and dried. The wafer (5) thus developed is taken out of the hermetic chamber (8) by the carry-out handling arm (7).

These steps are repeated to develop a plurality of wafers (5).

In the above embodiment, the developing gas containing the alkali element is filled in the hermetic chamber (8), and the developing process is performed in a state where the wafer (5) is stored in the hermetic chamber (8) in advance. The hermetic chamber (8) may be filled with a developing gas containing an alkali element, and the wafer (5) may be passed through the hermetic chamber (8) for development, or a gas having developing characteristics may be used. Any may be used.

In the above embodiment, the wafer (5) is washed after developing in the single hermetic chamber (8). However, as shown in FIG. 3, the hermetic chamber (D) for dry developing the wafer (5) is processed. The washing room (21) for washing and the washing room (21) may be installed independently.

In the above embodiment, the developing gas is blown down from top to bottom. However, as shown in FIG. 4, the developing gas (22) may be introduced left and right, for example, from left to right to fill the space. .

In the above embodiment, since the resist film on the wafer is developed with a developing gas containing an alkali element compound, the developing gas can be easily removed from the wafer. Can be stopped immediately. Due to this stop, excessive development processing of the wafer can be prevented.

Further, in order to excite the developing gas, the electron beam and μ may be processed by being turned into plasma by electric discharge or the like. In this case, a dome-shaped mechanism that presses the periphery is desirable in consideration of the adhesion of the substrate such as a wafer to the mounting table.

In the above embodiment, an example in which the present invention is applied to a developing process after resist exposure of a semiconductor wafer is described. However, any developing process may be used. For example, a developing process for a substrate having a liquid crystal driving circuit, a developing process for a printed board, and the like. It can be applied to any of them.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a dry developing apparatus for explaining an embodiment in which the method of the present invention is applied to a semiconductor wafer developing step.
FIG. 3 is a cross-sectional view for explaining a step of developing a wafer using the method of FIG. 1. FIG. 3 is another method in which an airtight chamber and a cleaning chamber are made independent in the method of FIG. FIG. 4 is an explanatory view of a dry developing apparatus for explaining another method of FIG. 1, and FIG.
FIG. 1 is a sectional view of a wafer for explaining a process of developing a wafer by a conventional method. 5 wafer 6 developing processing chamber 6a upper cup 6b lower cup 7 loading handling arm (unloading handling arm) 8 airtight chamber 9 spinner 13 cleaning solution 14 ... Cleaning nozzle 18 ... Load lock chamber, 19 ... Exposure equipment

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-250125 (JP, A) JP-A-63-228616 (JP, A) JP-A-59-24846 (JP, A) JP-A 60-250 234324 (JP, A) JP-A-62-45114 (JP, A) JP-A-58-103045 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03F 7/36, 7 / 26

Claims (5)

(57) [Claims] A step of loading a processing object having a resist film on which an exposure pattern is formed into a processing chamber; a step of reducing the pressure in the processing chamber; and a step of supplying a developing gas into the processing chamber to form a resist on the processing object. A step of developing the exposure pattern of the film, and after a predetermined development time, supply of the developing gas into the processing chamber is stopped to introduce the atmosphere into the processing chamber and exhaust the processing chamber. A developing method, comprising: a step of supplying a cleaning liquid to wash an object to be processed, and thereafter drying the object to be processed; and a step of opening a processing chamber and taking out the object to be processed. 2. A step of loading an object having a resist film on which an exposure pattern is formed into a processing chamber; a step of depressurizing the processing chamber; and a step of supplying a developing gas into the processing chamber to resist the object. A step of developing the exposure pattern of the film, and after a predetermined development time, supply of the developing gas into the processing chamber is stopped, an inert gas is introduced into the processing chamber, and the processing chamber is purged and the processing chamber is exhausted. And a step of supplying a cleaning liquid to the object in the processing chamber to clean the object, and thereafter drying the object, and a step of opening the processing chamber and taking out the object. Development method. 3. The developing method according to claim 1, further comprising a step of detecting an end point of the development. 4. The developing gas according to claim 1, wherein said developing gas contains an alkali element compound.
The developing method according to any one of the above. 5. The developing method according to claim 1, wherein the object to be processed is heated or cooled according to a type of a developing gas.