JPH07107604B2 - Resist development method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a resist developing method for performing favorable development by reducing the undeveloped residue of a resist pattern.

[Prior Art] Generally, in forming a resist pattern on a substrate, a resist is uniformly deposited on the substrate, a pattern mask is placed on the resist to perform exposure, and the resist is cured according to the pattern. In the development process, the cured resist is left, and the uncured resist is removed.
A resist pattern is formed.

In such a developing process, in order to reduce the undeveloped portion of the resist pattern and perform good development, conventionally, ultrasonic waves are applied to the developing solution or the substrate on which the resist pattern is formed is shaken. Has been done. Although ultrasonic waves are effective, uneven development, that is, areas where development is insufficient, is likely to occur, so it is necessary to apply ultrasonic waves for a long time, and as a result, the resist in the cured portion may peel off. In the case of rocking, it is impossible to completely eliminate the development residue only by rocking, and moreover, the edge portion of the developed resist layer is dull as compared with the case of applying ultrasonic waves.

[Problems to be Solved by the Invention] Accordingly, an object of the present invention is to provide a resist developing method which eliminates the above-mentioned drawbacks and favorably develops the resist.

[Means for Solving the Problem] In order to achieve such an object, the present invention provides a resist developing method in which a substrate on which an exposed resist layer is formed is immersed in a developing solution to perform a developing treatment. The substrate is immersed in the developing solution while applying ultrasonic waves to the substrate for 1/20 to 1/2 of the entire time in which the substrate is immersed in the developing solution in the first half. It is characterized in that the substrate is rocked over a period of time.

Here, the ultrasonic wave application time is 1/20 to 1 / of the total immersion time.
It is preferably 2 and more preferably 1/15 to 1/4. It is also preferable to apply ultrasonic waves immediately after the immersion of the substrate.

[Operation] According to the present invention, the uncured portion can be almost completely removed without peeling off the cured portion of the resist, and thus the resist edge portion can be sharpened to form a resist pattern, Good resist development can be performed.

[Examples] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a developer tank 2 in which a substrate 1 on which an exposed resist layer is formed is immersed when development is performed according to the present invention.
The ultrasonic transducer 3 is arranged in the tank 2 to propagate the ultrasonic wave to the substrate 1 in a predetermined direction. Reference numeral 4 is a rocking device for rocking the substrate 1 in a predetermined direction.

In the present invention, ultrasonic waves are applied to the resist substrate 1 from the ultrasonic oscillator 3 during development, and in combination with the ultrasonic waves, the substrate 1 is swung by the swinging device 4. In that case, for the time of applying the ultrasonic wave, when the ultrasonic wave is applied in the latter stage of the development, peeling of the cured portion of the resist increases, so it is preferable that the time is less than 1/2 of the time of the developing step. Apply ultrasonic waves. More preferably, the application of ultrasonic waves is started before 1/4 of the previous step, and further preferably from the first point of development. In the present invention, in order to uniformly apply the ultrasonic wave to the resist, the substrate 1 is mechanically swung in the same direction as the ultrasonic wave is transmitted. From the viewpoint of the efficiency of the layer 2, it is preferable that the pitch of the rocking is as small as possible within a range longer than the wavelength of the ultrasonic waves. Preferably, (wavelength) ≦ oscillation pitch ≦ (wavelength) × 20. More preferably, 2 × (wavelength) ≦ oscillation pitch ≦ (wavelength) × 10. For example, a swing pitch of 5 cm for a wavelength of 1.3 cm
And

The rocking speed is preferably as high as possible within the range where no load is applied to the substrate 1. Preferably, 2 cm / sec ≦ oscillation linear velocity ≦ 50 cm / sec. More preferably, 5 cm / sec ≦ oscillation linear velocity ≦ 25 cm / sec.

Further, changing the strength and movement of ultrasonic waves, or moving the position of the ultrasonic source 3 is also effective for good development, but considering the structure of the tank 2 and so on, ultrasonic development It is most preferable to use both and rocking together.

Next, examples will be described to further clarify the aspects of the present invention, but the present invention is not limited to the following examples, and it is needless to say that various modifications can be made.

"Nagase negative resist 747" is applied on a copper foil with a thickness of 80 μm and dimensions of 650 × 400 so that the thickness after curing becomes 4 μm, and then it is exposed by covering it with a mask pattern and exposing Cured. Then, it was developed under the following conditions in three tanks by using a dedicated developer for the above resist.

In any of the first to third tanks, the substrate is fixed vertically to the bottom surface, the vertical stroke is 10 cm, and the linear velocity is 15 cm / sec.
It was immersed for 3 minutes while rocking. An ultrasonic oscillator was provided in the lower part of the first tank to propagate an ultrasonic wave of 50 KHz upward.
The ultrasonic wave transmission time was set to 0.5, 1 and 3 minutes in the order of Examples immediately after the substrate was immersed. The liquid temperature was 25 ° C. As the pattern, a striped pattern with a line width of 30 μm and 6 lines / mm was used. Here, ultrasonic waves were applied in the first tank only for the first minute, and all of the first to third tanks were shaken over the entire 3 minutes. Substrates are 3 each from the first tank to the third tank in order.
Soaked for a minute.

In addition to the examples of the present invention, the following Table 1 shows results as comparative examples when the ultrasonic wave application time and the rocking time were variously changed and when the rocking stroke was shortened.

As described above, according to the present invention, it was possible to obtain a copper foil having a resist pattern developed in a state where there is no peeling portion of the resist cured portion and no development residual portion of the resist uncured portion. Here, the time for simultaneously applying and shaking the ultrasonic waves is preferably 1/20 to 1/2 of the total immersion time, and particularly 1/1
It was found that the oscillation pitch of 5 to 1/4 is more preferable to be longer than the wavelength.

[Effects of the Invention] As is apparent from the above, according to the present invention, the uncured portion of the resist can be almost completely removed without peeling off the cured portion, thereby sharpening the edge portion of the resist. A resist pattern can be formed and good resist development can be performed.

[Brief description of drawings]

FIG. 1 is a diagram showing a developer tank for carrying out the present invention. 1 ... Resist substrate, 2 ... Developer tank, 3 ... Ultrasonic vibrator, 4 ... Oscillating device.

Claims (4)

[Claims] 1. A resist developing method in which a substrate on which an exposed resist layer is formed is immersed in a developing solution to perform a developing treatment, in which the substrate is immersed in the developing solution in the first half of the time. Ultrasonic waves are applied to the substrate for a period of 1/20 to 1/2 of the total time during which the substrate is shaken while the substrate is immersed in the developing solution. Method. 2. The resist developing method according to claim 1, wherein the time of applying the ultrasonic wave is 1/15 to 1/4 of the total time of immersing the substrate in the developing solution. A method for developing a resist, comprising: 3. The resist developing method according to claim 1 or 2, wherein the ultrasonic wave is applied to the substrate immediately after the substrate is immersed in the developing solution. Method. 4. The resist developing method according to claim 1, wherein the substrate is rocked in a longitudinal direction of the substrate, and the rocking direction and the ultrasonic wave are changed. A resist developing method characterized in that the transmission directions are set to be substantially the same.