JPH07271054A - Rinsing solution for photosensitive polyimide - Google Patents

Abstract

PURPOSE:To prevent the reduction of the temp. of a rinsing soln. and the formation of scum, to eliminate the danger of ignition in a developing-rinsing process and to enable stable use by incorporating a specified ester compd. and/or a specified ketone compd. CONSTITUTION:An ester compd. and/or a ketone compd. having >=23 deg.C flash point is incorporated and/or an ester compd. and/or a ketone compd. having >=100 deg.C b.p. is incorporated. At least one kind of ester compd. and/or at least one kind of ketone compd. selected from among ethyl lactate, ethyl pyruvate, propylene glycol monomethyl ether acetate, methyl-3-methoxy propionate, ethyl-3- ethoxy propionate, 2-heptanone, butyl acetate, propylene carbonate and diethyl carbonate may be incorporated in place of or in combination with the above- mentioned compds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rinse solution used in a rinse step for removing a developer used in a developing step of a photosensitive polyimide composition useful as an electronic material.

[0002]

2. Description of the Related Art Conventionally, lower alcohols such as methanol, ethanol and isopropanol have been mainly used as a rinsing solution for photosensitive polyimide (Japanese Patent Laid-Open No. 64-64-
No. 48857). However, such a rinse solution
When spray development or puddle development that is generally performed in semiconductor manufacturing processes is performed, the rinse solution evaporates quickly during development, and the temperature of the rinse solution decreases during the rinse process, causing the components dissolved by the developer to reattach and scum. It causes the occurrence. In addition, in the case of such a lower alcohol, since the flash point is lower than 23 ° C. which is the room temperature of a normal clean room, there is a drawback that there is a possibility of catching a spark when a spark is generated by a developing device in this type of process. there were.

[0003]

The present invention was devised in view of the above-mentioned drawbacks of the prior art. The object of the present invention is to reduce the liquid temperature of the rinse liquid and the generation of scum and the like due to this. Another object of the present invention is to provide a rinse liquid for a photosensitive polyimide which can be prevented and can be used safely without fear of ignition in the developing rinse step.

[0004]

The object of the present invention is as follows.
This is achieved by adopting the following configuration.

(1) A rinse liquid for a photosensitive polyimide, which comprises an ester compound and / or a ketone compound having a flash point of 23 ° C. or higher. (2) The rinse liquid for photosensitive polyimides according to (1) above, which contains an ester compound and / or a ketone compound having a boiling point of 100 ° C. or higher. (3) At least one selected from ethyl lactate, ethyl pyruvate, propylene glycol monomethyl ether acetate, methyl-3-methoxypropionate, ethyl-3-ethoxypropionate, 2-heptanone, butyl acetate, propylene carbonate and diethyl carbonate. The rinsing liquid for photosensitive polyimide as described in (1) above, which contains one kind of ester compound and / or ketone compound.

The ester compound and the ketone compound in the present invention have a flash point of 23 ° C. or higher from the viewpoint of preventing scum generation due to a decrease in liquid temperature during rinsing and avoiding ignition in the developing rinse step. Is necessary, 30
It is preferably at least ° C. For the same reason, the boiling point is preferably 100 ° C or higher, more preferably 120 ° C or higher. Preferred specific examples include ethyl lactate, butyl lactate, ethyl pyruvate, butyl pyruvate, propylene glycol monomethyl ether acetate, methyl-3-methoxypropionate, ethyl-3.
-Ethoxypropionate, 2-heptanone, butyl acetate, propylene carbonate, diethyl carbonate, dibutyl carbonate and the like can be exemplified. Among them, ethyl lactate, ethyl pyruvate, propylene glycol monomethyl ether acetate, methyl-3-methoxypropionate, ethyl-3-ethoxypropionate, 2-heptanone,
Butyl acetate, propylene carbonate, diethyl carbonate are particularly preferred. These may be used alone or in combination of two or more.

The total amount of the above ester compound and ketone compound is preferably 30% by weight or more in the rinse liquid.
A more preferable content is 50% by weight or more.

Benzene, which is another organic solvent, within a range that does not significantly deteriorate the characteristics of the rinse liquid of the present invention,
Toluene, xylene, dioxane, tetrahydrofuran, methanol, ethanol, isopropanol, ethyl acetate, n-butanol, iso-butanol, sec
-Butanol, tert-butanol, n-amyl alcohol, iso-amyl alcohol, n-hexanol, iso-hexanol, cyclohexanol and the like may be added.

The rinse liquid for photosensitive polyimide of the present invention is
All currently known photosensitive polyimides (eg,
JP-B-59-52822, U.S. Pat. No. 39575
No. 12, Japanese Patent Laid-Open No. 2-50161, and Japanese Society of Polymer Science, Proceedings p807 (1990)).

Next, a method of developing a photosensitive polyimide using the photosensitive polyimide rinse liquid of the present invention will be described.

First, a photosensitive polyimide varnish is applied onto a silicon wafer or the like by a method such as spin coating, and the solvent is scattered on a hot plate or in an oven. Then, after performing a predetermined amount of exposure, the wafer is fixed on a spinner, and a developing solution is sprayed while rotating at 50 to 3000 rotations per minute (spray development). Alternatively, the developing solution is placed on the wafer on the spinner and left standing to perform the development (paddle development). As another developing method, a relief pattern is obtained by developing by a method such as immersion development in which a wafer is immersed in a bath of a developer or irradiation of ultrasonic waves in immersion development.

After that, rinsing is performed using the rinsing liquid for the photosensitive polyimide of the present invention. As a rinsing method, there are a method of spraying a rinse liquid on a rotated wafer with a nozzle or a spray (spray rinse), a method of immersing the wafer in a rinsing bath, or a method of irradiating ultrasonic waves during immersion. From the characteristics of the rinse liquid of the present invention, it is preferable to perform the rinse by the spray rinse method. After this rinse step, 100 on the oven or hot plate
A final product is obtained by performing heat treatment at about ℃ to 450 ℃ and converting into polyimide.

[0013]

EXAMPLES The present invention will be specifically described below based on examples, but the present invention is not limited thereto.

Example 1 UR-3 manufactured by Toray Industries, Inc. as a varnish of photosensitive polyimide
1 on a 4-inch silicon wafer using 140
Spin coating was performed at 500 rpm for 30 seconds. Then 8
After drying at 0 ° C. for 1 hour, a contact aligner PLA-501 manufactured by Canon Inc. was used, and a test pattern 9-19A-1 manufactured by Dainippon Printing was used as a mask.
The wavelength of 200 nmJ / cm ^{2 was used} for exposure.

This sample was paddle-developed using a developer consisting of 70% by weight of N-methylpyrrolidone and 30% by weight of xylene using a clean track manufactured by Tokyo Electron Ltd.

The developing conditions are as follows: a developing solution is applied to a silicon wafer at 100 revolutions for 3 seconds and then left standing for 5 minutes for development, and butyl acetate (boiling point 126 ° C., flash point 2
Rinsing was performed by spraying (3 ° C.) at 500 revolutions.

During the rinsing, the temperature of the central part of the wafer is 20 ° C. and the temperature of the peripheral part is 18 in a clean room at 23 ° C.
It was ℃.

When the result of development was observed with an optical microscope, scum was not observed at all from the central portion to the peripheral portion, and uniform resolution was achieved.

Example 2 A polyimide film was formed in the same manner as in Example 1 except that propylene glycol monomethyl ether acetate (boiling point 146 ° C., flash point 46 ° C.) was used as the rinse liquid.
Developed and rinsed.

During the rinsing, the temperature of the central part of the wafer is 21 ° C. and the temperature of the peripheral part is 19 ° C. in a clean room of 23 ° C.
It was ℃.

When the result of development was observed with an optical microscope, no scum was observed from the central part to the peripheral part, and uniform resolution was achieved.

Example 3 Ethyl lactate (boiling point 154 ° C., flash point 46
A polyimide coating was formed, developed and rinsed in the same manner as in Example 1 except that (.degree. C.) was used.

During the rinsing, the temperature of the central part of the wafer was 21 ° C. and the temperature of the peripheral part was 19 ° C. in a clean room at 23 ° C.
It was ℃.

When the result of development was observed with an optical microscope, no scum was observed from the central part to the peripheral part, and uniform resolution was achieved.

Example 4 A polyimide film was formed, developed and rinsed in the same manner as in Example 1 except that propylene carbonate (boiling point 240 ° C., flash point 132 ° C.) was used as the rinse liquid.

During the rinsing, the temperature of the central part of the wafer is 22 ° C. and the temperature of the peripheral part is 20 in a clean room at 23 ° C.
It was ℃.

When the result of development was observed with an optical microscope, no scum was observed from the central part to the peripheral part, and uniform resolution was achieved.

Comparative Example 1 A polyimide film was formed, developed and rinsed in the same manner as in Example 1 except that isopropanol (boiling point 82 ° C., flash point 22 ° C.) was used as the rinse liquid.

During the rinsing, the temperature of the central part of the wafer is 17 ° C. and the temperature of the peripheral part is 15 in a 23 ° C. clean room.
It was ℃.

When the results of development were observed with an optical microscope, scum was observed in several places in the large area of the punched portion from the central portion to the peripheral portion.

Comparative Example 2 Ethyl acetate (boiling point 76 ° C., flash point -3 as rinsing liquid
A polyimide coating was formed, developed and rinsed in the same manner as in Example 1 except that (.degree. C.) was used.

During the rinsing, the temperature of the central part of the wafer is 17 ° C. and the temperature of the peripheral part is 15 in a 23 ° C. clean room.
It was ℃.

When the results of development were observed with an optical microscope, scum was observed in several places in the large area of the punched portion from the central portion to the peripheral portion.

[0034]

INDUSTRIAL APPLICABILITY The present invention uses an ester compound and / or a ketone compound having a flash point of 23 ° C. or higher as a rinse liquid for a photosensitive polyimide, and lowers the temperature of the rinse liquid and scum resulting therefrom. It is possible to reliably prevent the occurrence of the above, and there is an advantage that it can be used safely without fear of ignition in the developing and rinsing step.

Claims (3)

[Claims] 1. A rinsing liquid for a photosensitive polyimide, which comprises an ester compound and / or a ketone compound having a flash point of 23 ° C. or higher. 2. A compound containing an ester compound and / or a ketone compound having a boiling point of 100 ° C. or higher.
The rinsing liquid for the photosensitive polyimide described. 3. Ethyl lactate, ethyl pyruvate, propylene glycol monomethyl ether acetate, methyl-
A compound containing at least one ester compound and / or ketone compound selected from 3-methoxypropionate, ethyl-3-ethoxypropionate, 2-heptanone, butyl acetate, propylene carbonate and diethyl carbonate. Item 2. A rinsing liquid for photosensitive polyimide according to Item 1.