JPH0119256B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a pattern forming method for forming a desired pattern on a desired substrate using a layer made of a conductive material, an insulating material, etc., and in particular to a semiconductor integrated circuit device, Josephson integrated circuit It is suitable for application when forming a conductor layer, an insulating layer, etc. of a device or the like into a desired pattern.

Conventionally, as a method for forming such a pattern, the method described below with reference to FIG. 1 has been proposed in principle.

That is, the required substrate 1 is prepared in advance (FIG. 1A),
Then, on the substrate 1, a stencil layer 2 made of photoresist, electron beam resist, etc. (in fact, a flange 5 extending outward from the upper edge is formed).
is formed into a desired pattern (FIG. 1B), and then a layer thinner than the stencil layer 2 made of a conductive material, an insulating material, etc. is formed on the area on the substrate 1 where the stencil layer 2 is not formed. Thickness layer 3, stencil layer 2
At the same time, a layer 4 made of the same conductive material, insulating material, etc. as layer 3 and having the same thickness as layer 3 is formed on top of the substrate 1. The stencil layer 2 is formed by vapor deposition, sputtering, etc. (FIG. 1C), and then the stencil layer 2 is removed from the substrate 1 by dissolving it using the solvent, and Along with this, a method is proposed in which layer 4 on stencil layer 2 is removed (FIG. 1D) and a desired pattern (a pattern that can be reversed from stencil layer 2) of layer 3 is formed on substrate 1. has been done.

However, in the case of such a pattern forming method, in principle,
In the step of forming layer 3 on the region of substrate 1 where stencil layer 2 is not formed, together with the formation of layer 4 on stencil layer 2 (hereinafter referred to as the second step for simplicity) , the layers 3 and 4 are formed separately from each other since they have a smaller thickness than the stencil layer 2. However, in practice, in the second step of forming the layers 3 and 4, the fine particles of the material constituting the layers 3 and 4 are scattered,
By diffusion etc., a thin layer 6 of the same material as that of layers 3 and 4 is formed, as shown in FIG.
is forced to be deposited on the side surfaces of stencil layer 2 in a manner that connects layers 3 and 4.

Therefore, by dissolving the stencil layer 2, the stencil layer 2 is removed from the substrate 1, and at the same time, the layer 4 on the stencil layer 2 is removed.
In the step of removing the stencil layer 2 (hereinafter referred to as the third step for simplicity), the stencil layer 2 is conventionally immersed in the solvent (in practice, the substrate 1 on which the stencil layers 2, 3, and 4 are formed is immersed in the solvent). Using an ultrasonic oscillator with an oscillation frequency of 25 to 50 KHz, the stencil layer 2 is immersed in the solvent of 25 to 50 KHz.
A process is used in which ultrasonic vibrations having a frequency of 50 KHz are applied to dissolve the stencil layer 2 while destroying the layer 6.

However, when such a treatment is performed in the third step, if the vibration output of the ultrasonic wave is increased, there is a problem that defects such as peeling or chipping of the layer 3 from the substrate 1 occur. Ta. In addition, in order to avoid such inconvenience, if the vibration output of the ultrasonic wave is made small, the layer 6 attached to the side surface of the stencil layer 2 will not be effectively destroyed, so the stencil layer 2 is removed from the substrate 1. It takes a long time to do this, and the layer 4 on the stencil layer 2 remains as an unnecessary layer 4' on the substrate 1 as shown in FIG. 6', a residue 6'' attached to the layer 3, or a residue 6 attached to an area of the substrate 1 where the layer 3 is not formed; It takes a long time to obtain the desired pattern by the layer 3, and the desired pattern by the layer 3 is obtained with unnecessary layers 4', residues 6', 6'', 6, etc. remaining. Was.

In view of the above, the present inventors conducted various experiments in the pattern forming method described above in FIG. When applying ultrasonic vibrations with a frequency of 25 to 50 KHz to the stencil layer 2 while the stencil layer 2 is immersed in Not only does the low power not effectively destroy the layer 6 deposited on the side surfaces of the stencil layer 2, but the ultrasonic frequency of 25-50 KHz also causes damage to the layer 6. We have come to the conclusion that this may also be caused by destruction not being done effectively.

In addition, the present inventors, in the third step mentioned above,
As described above, instead of applying ultrasonic vibrations having a frequency of 25 to 50 KHz to the stencil layer 2 while the stencil layer 2 is immersed in the solvent, the stencil layer 2 is immersed in the solvent. When applying ultrasonic vibrations with a frequency of 80 to 200 KHz to the stencil layer in a state where the It has now been confirmed that the layer 6 deposited on the side surface of the stencil layer 2 is effectively destroyed, and the above-mentioned disadvantages can therefore be effectively avoided.

Furthermore, in the third step mentioned above, the present inventors applied a temperature of 80 to 200 K to the stencil layer 2 while immersing the stencil layer 2 in the solvent.
When applying ultrasonic vibration having a frequency of Hz (hereinafter referred to as the third process for simplicity), before the third process, the stencil layer 2 is
, by using a mixture of a good solvent and a poor solvent (hereinafter, this will be referred to as the first treatment for simplicity). Even if the layer 6 described above is formed, it is thin, and the mixed liquid described above penetrates into the stencil layer 2 through it.
), the swelling of the stencil layer 2 imparts mechanical stress to the layer 6, so in the third step described above, the stencil layer It has now been confirmed that the layer 6 attached to the side surface of the substrate 2 can be more easily destroyed, and therefore the effect of effectively avoiding the above-mentioned disadvantages is further improved.

Furthermore, in the third step, when the above-mentioned third treatment is performed, the present inventors have prepared the stencil layer 2 in a good solvent before the third treatment. If the stencil layer 2 is immersed in water and subjected to a process of applying ultrasonic vibrations having a frequency of 20 to 50 kHz (hereinafter referred to as the second process for simplicity), the stencil layer 2 will have a frequency of 20 to 50 kHz. 50k
When ultrasonic vibrations having a frequency of Hz are applied in the good solvent of the stencil layer 2, internal strain is generated in the stencil layer 2, and therefore, the above-mentioned second process is performed and then the above-mentioned third process is performed. When the above treatment is carried out, the good solvent of the stencil layer 2 in the third treatment rapidly penetrates into the stencil layer 2,
Stencil layer 2 when using the third process
It has been confirmed that the layer 6 attached to the side surface of the structure is more easily destroyed, and therefore the effect of effectively avoiding the above-mentioned disadvantages is further improved.

In addition, the above-mentioned confirmation items are the first case where the above-mentioned first process and the above-mentioned third process are performed sequentially in the above-mentioned third step, and the above-mentioned second process and the above-mentioned third process. The stencil layer 2 and the layer 4 above it are as described above in FIG. As a result of measuring the rate (%) of removal from the substrate 1 without leaving unnecessary layers 4', residues 6', 6'', 6, etc., the results shown in Figure 4 were obtained. In Figure 4, ● and ○ marks indicate the first case mentioned above, and ■ and □
The marks indicate the second case mentioned above, and the white marks indicate that unnecessary layers, residues, etc. have been removed, and the black marks indicate that unnecessary layers, residues, etc. have been removed. This shows that it was not done. In addition, in the third step described above, in either of the first and second cases described above, the desired pattern formed by the layer 3 is removed from the unnecessary layer 4' and the residual material, as shown in FIG. 6′, 6″, 6
The fact that it was obtained in a short period of time as a clear image with no traces left behind confirmed its authenticity. However, the results shown in FIGS. 4 and 5 show that the stencil layer 2 has a thickness of about 1 μm and the AZ-1470
(trade name manufactured by Shipplay) is a positive type photoresist, and layers 3 and 4 have a thickness of 0.4 μm and are made of a lead alloy.
In this process, the good solvent for the stencil layer 2 is monochlorobenzene, the poor solvent is ethanol, which is 3% by volume of the good solvent in this case, and the third
The good solvent for the stencil layer 2 in the second treatment in the process is acetone, and the ultrasonic vibration output in the second treatment is 10W in terms of the electrical input of the ultrasonic oscillator. The solvent of the stencil layer 2 in the third process in the third process mentioned above is acetone, and the vibration output of the ultrasonic wave in the third process is based on the electric input of the ultrasonic oscillator.
This is the result when the power is 200W. However, in addition to the stencil layer 2 being made of AZ-1470 positive photoresist, AZ-1350J, AZ-1450J, AZ-2400 (all product names manufactured by Shippray Co., Ltd.) positive photoresist, OFPR series (manufactured by Tokyo Applied Chemical Co., Ltd.) Product name)
Even if layers 3 and 4 are made of lead alloy, other conductive materials, or insulating materials such as _SiO2 ,
Furthermore, the good solvent and poor solvent in the first treatment described above are monochlorobenzene and ethanol, respectively, and even if other necessary good and poor solvents are used,
Furthermore, even if the solvent for the stencil layer 2 in the second and third treatments described above is acetone, it may be a good solvent depending on the material constituting the stencil layer 2. When 2 is a photoresist or an electron beam resist, ketones such as methyl isobutyl ketone, 2-
Even with acetic acid esters such as ethoxylacetate, similar results were obtained as shown in FIG. 4.

In addition, in the confirmation items mentioned above, in the third process in the third process mentioned above, the frequency of the ultrasonic wave is
Its lower limit frequency is 80kHz, which is 80~200kHz
This is also determined from the fact that if the ultrasonic frequency becomes lower than the lower limit frequency of 80 kHz, the processing time for applying ultrasonic vibration to the stencil layer 2 with the lower limit frequency set as Sakai will suddenly become longer. be. Moreover, the upper limit frequency of 200 kHz is such that if the frequency of the ultrasonic wave becomes higher than the upper limit frequency of 200 kHz, the loss of vibration output of the ultrasonic wave in the solvent of the stencil layer 2 will suddenly increase, and this This is also determined by the fact that it becomes impossible to effectively apply ultrasonic vibration output to the stencil layer 2.

Based on the above, we have hereby proposed the pattern forming method described in Claims 1 and 2 as a pattern forming method according to the present invention.

According to the pattern forming method according to the present invention, it is possible to form a conductive material and an insulating material on a required substrate 1 without the above-mentioned disadvantages, although detailed explanation will be omitted since it is obvious from the above-mentioned points. A great feature is that a desired pattern can be formed using the layer 3 made of a rubber material or the like. Incidentally, as mentioned above, the stencil layer 2 has a thickness of 1 μm and is made of AZ-1470 photoresist, and the layers 3 and 4 have a thickness of 0.4 μm and are made of a lead alloy.
Furthermore, when the first and third treatments are performed in the third step described above, the good solvent and poor solvent for the stencil layer 2 in the first treatment may be motochlorobenzene and the like, respectively, as described above. against 3
% by volume of ethanol, the frequency of the ultrasonic wave in the first treatment is 45 kHz, the vibration output is 10 W in terms of the electrical input of the ultrasonic oscillator, and the second and In the case of the third treatment, the stencil layer 2 in the second treatment
Acetone is a good solvent for the stencil layer 2 in the third treatment in the third step described above, and furthermore, acetone is a good solvent for the stencil layer 2 in the third treatment in the third step described above. The ultrasonic vibration output in the ultrasonic oscillator's electrical input
In the case of 200W, the process of applying ultrasonic vibration in the third step mentioned above was 3 to 30 minutes, and the frequency of the ultrasonic wave was 100kHz or 150kHz. As shown in Figure 5, the substrate 1
The desired pattern by layer 3 is formed on the substrate 1 by forming unnecessary layers 4', residues 6', 6'', 6 as described above in FIG.
etc., without leaving any residue. In the case of this example, after the above-mentioned third step, the whole was rinsed in acetone solution and then dried.

[Brief explanation of drawings]

1A to 1D are schematic cross-sectional views of the sequential steps of the fundamental pattern forming method that is the basis of the pattern forming method according to the present invention, and FIG. 2 corresponds to the step of FIG. 1 C. FIG. 3 is a schematic cross-sectional view of an actual process corresponding to the process of FIG. 1D when a conventional pattern forming method is used; FIG. 5 is a curve diagram for explaining the pattern forming method according to the present invention, and FIG. 5 is a schematic cross-sectional view in the step shown in FIG. 1D when the pattern forming method according to the present invention is used. In the figure, 1 is a substrate, 2 is a stencil layer, 3, 4, and 6 are layers, 4' is an unnecessary layer, and 6', 6'', and 6 are residues.

Claims (1)

[Claims] 1. A first step of forming a stencil layer having a desired pattern on a desired substrate, and forming a desired first layer on a region of the substrate where the stencil layer is not formed. , a second step of forming a second layer on the stencil layer, and removing the stencil layer from the substrate by dissolving the stencil layer; and a third step of removing the second layer, in which the second step removes the stencil layer from its good quality. A swelling treatment is performed using a mixture of a solvent and a poor solvent, and following this treatment, the stencil layer is immersed in the good solvent, and the stencil layer is exposed to ultrasonic waves having a frequency of 80 to 200 kHz. A pattern forming method characterized by including a process of applying vibration. 2. A first step of forming a stencil layer with a desired pattern on a desired substrate, and forming a desired first layer on a region of the substrate where the stencil layer is not formed, and forming a desired first layer on the stencil layer. A second step of forming a second layer, and removing the stencil layer from the substrate by dissolving the stencil layer, and thereby removing the second layer. and a third step of removing the stencil layer to form a desired pattern using the first layer, wherein the second step is immersing the stencil layer in its good solvent. The stencil layer is subjected to ultrasonic vibration with a frequency of 20 to 50 kHz while the stencil layer is in a state where the stencil layer is immersed in a good solvent. A pattern forming method characterized by comprising: applying ultrasonic vibrations having a frequency of .