JPH0395559A - Dry developing method - Google Patents

Abstract

PURPOSE:To prevent a body to be processed from being developed excessively by developing the body to be processed by bringing it into contact with developing gas. CONSTITUTION:A wafer 5 which is exposed by an exposure device 19 is moved into an airtight chamber 8 by a carry-in handling arm 7 in a load lock chamber 18 and supported on the top surface of a spinner 9 provided in the center in the airtight chamber 8. In this state, negative pressure is produced in the airtight chamber 8 and when the specific negative pressure is reached, a switching valve 12c is switched to the side of a developing gas source 12a. The developing gas which contains alkali element compound is admitted to the airtight chamber 8 from the side of a developing gas source 12a to fill the chamber. An infinite number of molecules of the developing gas filling the chamber contact and stick on the surface of the wafer 5 supported on a spinner 9. Thus, excessive development processing is precluded and development is carried out.

Description

[Detailed description of the invention] [Purpose of the invention] (Industrial application field) The present invention relates to a dry developing method.

(Prior Art) Conventionally, the manufacturing process of semiconductor devices includes a resist coating process, an exposure process, and a development process. Conventionally, this developing process is performed as follows. That is, in the development treatment of a resist film formed by adding a quinone diazide material as a photosensitizer to a phenol/borac resin material, an alkaline developer mainly containing tramethylammonium hydroxide is applied to a semiconductor wafer substrate (hereinafter referred to as (abbreviated as wafer) is spin-coated on the surface and developed. In this developing method, a mostly liquid developing material is supplied onto the surface of the wafer through 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 to the extent that the developer (2) does not fall off. A method of processing, a method of immersing the wafer (2) in a developer (2), a method of spraying a developer on the surface of the wafer (1), and a method of accumulating the developer (2) on the surface of the wafer (1) for development. There is. In any case, the wafer (υ
A liquid developing substance is added thereto, and this method is described in JP-A-5633834, JP-A-57-1228, JP-A-57-32445, JP-A-57-166032, and JP-A-57. -192955, JP-A-57-20
No. 8134, JP-A-58-4147, JP-A-58-
52645, JP 59-46649, JP 5950440, JP 60-126651, JP 61-147256, JP 62-239532
It is described in many publications such as No.

(Problems to be Solved by the Invention) Furthermore, there is a Utility Model Application Publication No. 58-98640 that uses liquid and gas for development, and a method that uses plasma discharge to dry develop a resist formed on a substrate. There is No. 58-103045, etc. However, the conventional wafer development method is a method of developing the resist film attached to the wafer (1) using a liquid developing substance (developer).
When fixing 3), the developer (2) cannot be quickly removed from the wafer, resulting in excessive development, for example, even the resist film on the unexposed portions of the wafer is developed (dissolved). This excessive development is particularly important for recent IM, 4M, and 16M
This has caused problems in forming fine circuit patterns on wafers such as 64M ultra-high density ICs, and improvements have been sought.

That is, as shown in FIG.
After developing the wafer (
1) to remove the developer (2) from the wafer (1).
is rotated at high speed by a rotating mechanism (not shown) to remove the developer (2).
I'm shaking it off. However, a small amount of developer (2) remains in a part of the wafer (2), and this residual developer (2) remains.
) is developing a portion of the wafer (1).

This development dissolves the resist film (2) up to the unexposed part (4) of the wafer (D).In other words, the resist film (2) up to the unexposed part (4) of the wafer (D) is dissolved.In other words, it is developed excessively than the prescribed development process, so a fine circuit pattern is formed on the wafer (1). However, it was difficult.

SUMMARY OF THE INVENTION An object of the present invention was made in view of the above problems, and it is an object of the present invention to provide a dry developing method that prevents excessive development of an object to be processed.

[Structure of the invention]

(Means for Solving the Problems) The present invention is characterized in that development processing is carried out by contacting with a developing gas.

Further, after making the container in which the object to be processed is stored airtight, and after evacuating this airtight chamber to a predetermined degree of accuracy, developing gas is introduced into this airtight chamber to fill it, and the above-mentioned The object to be processed is being developed.

(Operation and Effect) In the present invention, since the object to be developed is developed with a developing gas, the developing gas in the atmosphere can be removed to stop the development process immediately after the development of the object to be processed is completed.

In other words, since the object to be processed is developed with a developing gas, the developing gas contains an image substance floating in the state of independent molecules, and these independent molecules adhere to the object to be processed and develop it. By removing the molecules from the object to be processed, the independent molecules disappear from the periphery of the object, and when the developing gas disappears from the periphery, the development process is stopped.

Therefore, excessive development processing of the object to be processed can be prevented. Since this excessive development can be prevented, a highly accurate circuit pattern can be formed on the object to be processed.

Furthermore, if the airtight chamber is sucked to a negative pressure before the developing gas is introduced into the airtight chamber, and then the developing gas is introduced and filled, the developing gas will come into contact with the object to be processed evenly. It is possible to prevent uneven development and make a highly accurate circuit pattern appear on the object to be processed.

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

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

In this development process, a development processing chamber filled with development gas is
This is done using a dry developing device that develops a wafer.

As shown in Fig. 1, the structure of the dry developing apparatus is as follows: The exposed wafer 0 is isolated from the atmosphere and airtightly provided, and this airtight chamber is filled with a developing gas to perform development. a transport unit that transports the exposed wafer ■ to the development processing chamber 0;
For example, the carry-in handling arm 0 and the development processing chamber 0
It consists of an unloading section, for example, an unloading handling arm ω, which takes out the wafer 0 developed therein from the developing processing chamber (1).

The development processing chamber 0 is provided in an airtight manner.

In other words, a cylindrical cup whose top surface is closed with a plate-like object,
For example, a stainless steel upper cup (6(1)) with a diameter of 400 m + x height 150 mm x plate thickness 2 mm, and a cylindrical lower cup whose bottom is closed with a plate, for example, a diameter of 400 mm x height 1
50nnX plate thickness 2lTII1 stainless steel lower cup (6
b) Seal member, for example, outer diameter 405mm x inner diameter 39mm
It is airtightly installed via a neoprene O-ring (6c) measuring 5mm x 6m high.

The upper cup (6 (1)) is connected to a lifting mechanism (2) so that it can move up and down in the vertical direction. In other words, the upper cup (6 (1)) and the lower cup (6b) match to open the airtight chamber (8). As it looks, wafer 0 is in a predetermined position in this airtight chamber (8).
For example, to check whether the upper surface of the airtight chamber (9) has been reached, or when repairing a problem that has occurred in the airtight chamber (8), the upper cup (6 (1) is separated from the fixed lower cup (6b)). A lifting mechanism (8) is provided to open the inside of the airtight chamber (8).

The upper cup (
6(1) is installed so that one discharge is directed toward the surface of a spinner (9), which will be described later. At the tip of this nozzle (10), a diffuser plate (11) that introduces and disperses the developing gas containing the alkaline element compound into the airtight chamber (8) and fills the airtight chamber (8) is connected to the spinner (8) surface. They are placed so as to face each other.

A supply system (12) for introducing developing gas and atmosphere into the airtight chamber (8) is provided at the end opposite to the nozzle (10). This 0 (feeding system (12) is the above nozzle (10)
and a developing gas source containing an alkaline element compound (1 2a
) are connected to each other by piping. An air supply system (12 (1)
) is provided. A switching valve (
12c) is provided.

7--8- That is, the airtight chamber (8) is provided so that when developing the wafer 0, a developing gas containing an alkaline element combination is introduced into the airtight chamber (8). Also, developed wafer 0
When fixing the air, switch the switching valve (12c) to the air supply system (12(
1), the atmosphere is introduced into the airtight chamber (8).

The upper surface of the upper cup (8 (1) forming the airtight chamber (8) is the upper surface of the upper cup (8 (1)) that is formed by the molecules of the alkaline element compound gas attached to the wafer 0 and the dissolved gas after the wafer 0 is developed. A cleaning nozzle (14) for discharging a cleaning liquid (13) to remove the resist is provided in the upper cup (6(1)).

The cleaning nozzle (14) applies the cleaning liquid (13) to the wafer 0 based on a command from a control unit (not shown), for example, a CPU.
An on-off valve (15) for discharging is provided.

At the center of the lower cup (6b) forming the hermetic chamber (8), a spinner (9) is provided to place and support the transferred wafer (2). A rotating mechanism, such as a motor (16), is provided below the spinner (9) for shaking off the cleaning liquid (13) together with the dissolved resist when cleaning the wafer 0.

In addition, the lower cup (6b) is equipped with a cleaning liquid (1) for the wafer 0.
3) Discharge system (l7) that discharges the washed waste liquid
is placed vertically on the bottom.

The lower cup (6b) is provided with an on-off valve (17(1)) in order to make the airtight chamber (8) airtight after exhausting the gas in the airtight chamber (8) to the outside.

The carry-in handling arm 0 is installed in a load lock chamber (18) provided on the side of the airtight chamber (8),
It is installed so that the exposed wafer 0 can be transferred from the exposure device (19) side to the airtight chamber (8) side.

Further, the carry-in handling arm 0 is also used as a carry-out handling arm ω for taking out the developed wafer 0 from the airtight chamber (8) side to the outside.

Next, the operation will be explained.

First, a command signal is sent from the exposure device (19) to the control section of the dry developing device to develop the exposed wafer (5). Upon receiving this signal, the dry developing device processes the upper cup (6) according to a pre-stored program.
(1) is lowered to match the lower cup (6b) fixed below the upper cup (6(1). That is,
An airtight chamber (8) for dry developing wafer 0 is formed. The wafer 0 is transferred from the exposure device (19) side to the airtight chamber (1) using the carry-in handling arm 0 in the load lock chamber (18) provided between the airtight chamber (8) and the exposure device. That is, the wafer 0 is supported on the upper surface of a spinner (9) provided at the center of the airtight chamber (8). In this state, the wafer 0 transferred into the airtight chamber (8) is subjected to dry development processing.

That is, the dry development process is carried out in the airtight chamber, for example 25Q.
The volume of the airtight chamber (8) is set to a predetermined negative pressure value, for example 0.5 Torr.
Make the pressure negative to about r value.

Pressure sensor (not shown) installed in the airtight chamber (8)
It is sensed when the pressure reaches a predetermined negative pressure value, and this signal switches the switching valve (12c) to the developing gas source (12(1)).

A developing gas containing an alkaline element compound, e.g.
A gas quantity of Q is introduced at a flow rate, for example, 2 QCS flow rate, and is filled. At this time, it is desirable to operate the exhaust pump appropriately. As shown in FIG. 2 (1) and FIG. 2(b), the countless molecules P of this filled developing gas are
), which are in contact with the surface of the wafer 0 supported by the wafer 0. The rotational speed of the motor (l6) at this time can be selected as appropriate. Of course, it may be stopped. Furthermore, the wafer may be heated or cooled to an optimum temperature depending on the type of developing gas. Furthermore, development end point detection may be provided to automatically stop the development. The countless attached molecules P react with the exposed resist film (5(1)) and are developed (dissolved).The amount of this dissolution is the same as the amount of molecules P. Molecules P of the developing gas are again deposited on the resist film (5(1)) as shown in FIG. Dissolve 1) more deeply.

The development process may be terminated by purging a gas such as an inert gas at the same time as the development end point is detected. After the development is completed, the processed wafer is loaded into the un-11 12 through the load lock. The above-described method is repeated for the exposed resist film (5(1)) to perform a prescribed development.

Next, as shown in FIG. 2(d), when a predetermined developing time has elapsed, the supply of developing gas is stopped and the airtight chamber (8) is opened.
The switching valve (12c) is switched to the atmosphere piping side in order to remove the developing gas inside, that is, to supply the atmosphere into the airtight chamber (8). Then, the atmosphere is introduced into the airtight chamber (8), and the developing gas is exhausted from the exhaust system (17).

In this case, throughput can be improved by setting the wafer development processing space to a volume necessary to accommodate the wafer. Since the cursed gas is removed from the airtight water (8) by this exhaust, the phenomenon of sticking of molecules P of the developing gas to the surface of the wafer 0 is eliminated, and the developing process of the wafer 0 is stopped. In order to improve throughput, if a preliminary chamber is provided on the loader side, unloader side or in common of the development processing chamber, the throughput will further increase.
・Improves.

Next, as shown in FIG. 2(e), molecules P attached to the unexposed portion of wafer 0 and the dissolved resist film (5(
1) is removed with a cleaning solution (13).

Next, as shown in FIG. 2(f), the wafer (2) cleaned with the cleaning liquid (13) is rotated at high speed and dried.

The wafer (5) developed in this way is taken out from the airtight chamber (8) by the carry-out handling arm ω.

These steps are repeated to develop a plurality of wafers 0.

In the above embodiment, the airtight chamber (8) is filled with a developing gas containing an alkali element, and the development process is performed with the wafer 0 previously housed in the airtight chamber (8).
The airtight chamber (8) may be filled with a developing gas containing an alkaline element, and the wafer (5) may be passed through the airtight chamber (8) for development, or any gas having developing properties may be used. Anything is fine.

In the above embodiment, after developing in a single airtight chamber (8),
Although it has been described that wafer 0 is cleaned, as shown in FIG. 3, an airtight chamber (20) in which wafer 0 is dry-developed and a cleaning chamber (21) in which wafer 0 is cleaned may be installed independently.

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

In Example 2, the resist film on the wafer is developed with a developing gas containing an alkaline element compound, so the developing gas can be easily removed from the wafer, and along with this removal, the wafer is development can be stopped immediately. This stopping can prevent excessive development processing of the wafer.

Further, in order to excite the developing gas, processing may be performed by converting the electron beam and μ into plasma by discharge or the like. in this case,
Considering the adhesion of the substrate such as a wafer to the mounting table, it is desirable to have a dome shape and a mechanism to press the periphery.

In the above embodiment, an example was explained in which the application was applied to a developing process after resist exposure of a semiconductor wafer, but any developing process may be used, such as a developing process of a substrate equipped with a liquid crystal drive circuit, a developing process of a printed circuit board, etc. It can be applied to anything.

[Brief explanation of drawings]

The second royal diagram is an explanatory diagram of a dry developing device for explaining an embodiment in which the method of the present invention is applied to a semiconductor wafer developing process.
The figure is a wafer cross-sectional explanatory diagram for explaining the process in which a wafer is developed using the method shown in Figure 1. Figure 3 is another method in which the airtight chamber and the cleaning chamber are separated from each other in the method shown in Figure 1. FIG. 4 is an explanatory diagram of a dry developing device for explaining another method of FIG. 1, and FIG.
The figure is a wafer cross-sectional explanatory diagram for explaining a process in which a wafer is developed by a conventional method. 5... Wafer 6... Development processing chamber 6a...
・Upper cup 6b...Lower cup 7...Carry-in handling arm (Carry-out handle 1 herring arm)

Claims (3)

[Claims] (1) A dry developing method characterized by developing an object to be processed by bringing it into contact with a developing gas. (2) After making the container in which the object to be processed is stored airtight and evacuating this airtight chamber to a predetermined degree of vacuum, developing gas is introduced into the airtight chamber and filling it, and the object to be processed is A dry development method characterized by a development process. (3) A dry developing method, characterized in that the object to be processed is developed with a developing gas containing at least an alkaline element compound.