JP3058541B2 - Resist pattern forming condition determining method and resist pattern forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of determining resist pattern forming conditions for determining processing conditions such as resist film baking conditions and developing conditions in a resist pattern forming step formed on a substrate in the process of performing fine pattern processing. The present invention relates to a resist pattern forming method for forming a resist pattern under conditions determined by the resist pattern forming condition determining method.

[0002]

2. Description of the Related Art For example, in order to manufacture an LSI or a photomask, a fine pattern processing by a photolithography method is necessary. In the process of performing the fine pattern processing, a resist pattern used as an etching mask is formed. The resist pattern forming step includes a resist coating (forming) step, a resist baking step, an exposing step, and a developing step. Specifically, first, on the substrate to be processed,
For example, a resist is applied to a desired film thickness by a spin coating method. Next, in order to evaporate and remove the solvent of the resist, the substrate is allowed to stand in a hot-air circulating furnace (oven), on a hot plate, or the like and fired at a predetermined temperature and time according to the type of the resist. After baking the resist, the substrate to be treated with the resist film is cooled to about room temperature by natural leaving in a clean atmosphere or forced cooling. Thereafter, the substrate to be treated with the resist film is exposed by selectively irradiating an electromagnetic wave in a predetermined wavelength range corresponding to the type of the resist, for example, ultraviolet rays or a particle beam (for example, an electron beam) having a predetermined energy at a predetermined irradiation amount. I do. Thereafter, a desired resist pattern is formed through a development process.

By the way, a resist pattern is formed by baking conditions (temperature, time, baking method, etc.) in the resist film baking step and developing conditions (temperature, time, supplying method or amount of developing solution, etc.) in the developing step. The resist characteristics such as the amount of irradiation of electromagnetic waves necessary for the process, the shape quality of the obtained resist pattern, the dimensional accuracy of the resist pattern, and the characteristic of the adhesive strength to the underlying substrate greatly change. Therefore, baking conditions or developing conditions are important factors for forming a resist pattern with high precision, and these conditions need to be carefully determined. The determination of these conditions is, in theory,
By investigating all combinations of each condition, it is possible to independently and uniquely determine each optimum condition, but this combination is extremely enormous and cannot be implemented in practice.

Therefore, conventionally, the determination of the baking conditions of the resist film and the determination of the developing conditions have been performed as follows.

FIG. 6 is a diagram showing a work flow in a conventional method for determining a baking condition of a resist film. As shown in FIG. 6, after a resist is applied to a substrate to be processed and formed into a film, firing is performed by changing firing conditions. Next, the optimum exposure amount for each sample fired under a plurality of different firing conditions under certain development conditions is determined. The procedure for obtaining the optimum exposure amount is as follows. First, through a sample exposure step and a development step, a residual film sensitivity curve (a variation curve of the resist residual film thickness with respect to the exposure irradiation amount under a constant developing condition) is created. A rough exposure amount (irradiation amount of electromagnetic wave) necessary for formation is obtained. Next, through exactly the same procedure, a line width sensitivity curve (a variation curve of the resist pattern size with respect to the exposure irradiation amount under a constant developing condition) is created, and the optimal electromagnetic wave irradiation amount (optimum irradiation amount) under each firing condition is obtained. Exposure). In this case, the development conditions are fixed, and the optimum exposure amount (electromagnetic radiation amount) under each firing condition is determined.

Next, each sample is subjected to pattern exposure and development using the optimum exposure amount obtained in this way to actually form a resist pattern. The dimensional accuracy, shape quality of the obtained resist pattern, Evaluation of resist characteristics such as adhesion strength characteristics is performed. These evaluation results are compared and compared to make a comprehensive judgment, and the optimum firing conditions under certain development conditions are determined.

FIG. 7 is a diagram showing a flow of operations in a conventional method for determining development conditions. As shown in FIG. 7, this conventional developing condition determining method is performed in the same manner as the above-described firing condition determining method except that the developing condition is changed while the firing condition is kept constant. The evaluation results are compared and compared to make a comprehensive judgment, and the optimum development conditions under certain baking conditions are determined.

Thereafter, the evaluation results obtained in the above-described firing condition determining process and developing condition determining process are comprehensively determined, and finally the most suitable combination of the firing condition and the developing condition is selected and determined.

[0009]

In the above-mentioned conventional method, a resist is subjected to pattern exposure to actually form a pattern, and the obtained pattern is evaluated. That is, which firing condition or developing condition is optimal is determined based on the quality of the finally obtained pattern. For this reason, it is essential to perform pattern exposure after baking the resist. In addition, since the quality of the finally obtained pattern is determined, the conditions for obtaining the best pattern as the exposure conditions, development conditions, and other conditions are determined for each firing condition or development condition, and then the pattern is determined. Must be formed and evaluated.
Otherwise, it is not possible to determine whether the quality of the pattern is due to the baking conditions or developing conditions to be determined or other conditions. As a result, other conditions are inevitably determined for each baking condition or developing condition. For example, when determining the firing conditions, the optimum firing conditions are found from among several firing conditions, but the developing conditions are determined in advance as fixed conditions. Then, an optimum exposure condition is found, a pattern is formed by pattern exposure and development under the optimum exposure condition, and a comparative evaluation is performed. Therefore, the exposure conditions are necessarily determined. Also, in this case, it is necessary to select appropriate developing conditions so that a good pattern is formed even with fixed developing conditions, and the degree of dissolution of the resist greatly exceeds the appropriate range. It cannot be set as a condition. Therefore, for example, a method of freely selecting other conditions, such as development conditions, for the purpose of making it easy to make a judgment by greatly enlarging a difference in the quality of a pattern depending on a difference in firing conditions. Could not be adopted.

Due to such circumstances, according to the above-described conventional method, depending on the type of resist, etc., the difference in the quality of the pattern due to the difference in the firing conditions and the development conditions does not appear so large, or In many cases, it was not always easy to judge, for example, that if the exposure conditions were changed even under different baking conditions and developing conditions, there was no difference in the quality of the pattern.

That is, in the above-mentioned conventional method, the degree of the difference in the quality of the pattern depending on the difference in the firing conditions, in other words, the discrimination sensitivity is limited, and the quality of the pattern is not necessarily selected. The evaluation result of the resist pattern formed under the obtained conditions is, for example, poor, because it depends not only on the firing conditions and development conditions to be used but also on the combination of these and the exposure conditions to a degree that cannot be ignored. If so, it may not always be possible to determine whether it is due to firing conditions, to the amount of electromagnetic wave irradiation, or to development conditions. Further, even when the pattern evaluation result is good, there is a problem that whether or not the condition is the most suitable condition cannot always be determined.

Further, in the conventional method, when the firing conditions are determined, if a resist pattern is not formed at least three times on a sample prepared under each of the firing conditions under an arbitrary fixed developing condition, the firing conditions of the resist may be reduced. Not enough information can be obtained, so just performing this step
It requires considerable cost and time, including personnel and equipment. Furthermore, when determining the development conditions, the same evaluation must be performed under any fixed firing conditions. Therefore, the cost and time required to determine both the baking conditions and the developing conditions become substantial in proportion to the number of the baking conditions set and the number of the developing conditions set.

The present invention has been made under the above-mentioned background, and does not depend on exposure conditions and the like, and can optimize the conditions for baking or developing the resist film independently in a small number of steps. It is an object of the present invention to provide a method for determining a resist pattern forming condition that can be easily obtained and a method for forming a resist pattern under conditions determined by the method for determining a resist pattern forming condition.

[0014]

In order to solve the above-mentioned problems, a method for determining conditions for forming a resist pattern according to the present invention comprises the following steps: (1) a resist film forming step of forming a resist film on a substrate; A resist film firing step of firing the resist film formed by the forming step, an exposure step of subjecting the resist film fired by the resist film firing step to a predetermined pattern exposure using electromagnetic waves or particle beams, and a resist having passed through the exposure step A resist pattern forming condition determining method for determining a processing condition of any one or both of a resist film baking condition and a developing condition in a resist pattern forming process having a developing process of performing a developing process on the film, Prepare a plurality of formed resist films, bake them under different baking conditions, and expose them When the resist film fired under each firing condition is subjected to a developing solution treatment in which each of the resist films is partially dissolved under a predetermined developing solution and processing conditions, the resist film in which the tendency of dissolution among the resist films showed a desired tendency was shown. Is determined as a resist film firing condition, and a plurality of resist films formed on the substrate are prepared and fired under predetermined firing conditions,
When each of these baked resist films were subjected to developing solution treatment under different developing solution processing conditions and partially dissolved without subjecting them to exposure treatment, the dissolution tendency of each resist film showed a desired tendency. The developing condition is determined based on the developing solution processing condition of the resist film in the above case. As a mode of the configuration 1, (2) In the method for determining a resist pattern forming condition according to the configuration 1, the dissolution tendency may be determined. Wherein the desired tendency is determined when the degree of change in the thickness of the resist film before and after the dissolution is smallest, and (3) the method for determining a resist pattern forming condition according to the first aspect, wherein The configuration is characterized in that the case where the tendency is that the uniformity of the thickness of the resist film after dissolution is the highest is regarded as the desired tendency. According to another aspect of the present invention, (4) In the method for determining a resist pattern forming condition according to any one of the constitutions 1 to 3, the developing solution processing conditions when the resist film is processed by a developing solution to partially dissolve the resist film may be formed by forming the resist pattern And a resist according to the present invention, wherein the processing conditions are such that a residual film amount or a residual film ratio smaller than the residual film amount or the residual film ratio considered to be appropriate in the developing process is obtained. The pattern forming method includes: (5) a resist film forming step of forming a resist film on a substrate, a resist film firing step of firing the resist film formed by the resist film forming step, and firing by the resist film firing step. An exposure step of subjecting the resist film to a predetermined pattern exposure using an electromagnetic wave or a particle beam, and a development step of subjecting the resist film having undergone the exposure step to a development process In the method for forming a resist pattern, a condition determined by the method for determining a condition of forming a resist pattern according to any one of claims 1 to 4 is used as a baking condition of the resist film in the baking step of the resist film and a developing condition in the developing step. This is a configuration characterized by this.

[0015]

According to the above configuration 1, a plurality of resist films formed on a substrate are prepared and fired under different firing conditions, and each of the resist films fired under the respective firing conditions is not subjected to exposure processing. When a developer solution in which a part of the resist film is dissolved under a predetermined developing solution and processing conditions is applied, the firing condition of the resist film in which the tendency of dissolution among the resist films shows a desired tendency can be determined as the firing condition of the resist film, Also,
A plurality of resist films formed on a substrate are prepared and fired under predetermined firing conditions, and each of the fired resist films is subjected to a developing solution processing under different developing solution processing conditions without subjecting them to exposure processing. When dissolved, the developing conditions can be determined based on the developer processing conditions for the resist film when the dissolution tendency of each resist film shows a desired tendency.

This is because the tendency of the resist film to dissolve (hereinafter simply referred to as “dissolution tendency”) when the resist film is treated with a developing solution in which the resist film is partially dissolved under a predetermined developing solution and processing conditions without exposing the resist film is exposed. And the solubility of the pattern and the quality of the pattern formed by actual exposure and development of the pattern (hereinafter simply referred to as the quality of the pattern) depend on each other. Is based on the fact that the present inventors have found for the first time.

FIGS. 8 and 9 show this fact.
That is, FIG. 8 is a graph showing the relationship between the resist baking temperature T, the tendency of dissolution of the resist film (in-plane uniformity of the remaining film ratio and the remaining film thickness), and the quality of the pattern (in-plane dimensional accuracy of the pattern). FIG. 9 shows resist development conditions (developer supply amount f or developer supply time t in the spray development method).
And tendency of dissolution of resist film (residual film ratio and in-plane uniformity of remaining film thickness) and quality of pattern (pattern dimensional accuracy in plane)
6 is a graph showing a relationship with the graph.

In FIG. 8, the vertical axis represents the in-plane dimensional accuracy of the pattern (3σ; unit = μm, solid line), the remaining film ratio (unit =%, one-dot chain line), and the in-plane uniformity of the remaining film thickness (3σ). Unit = angstrom, two-dot chain line), and the horizontal axis is the resist baking temperature T (unit = ° C.).

In FIG. 9, the vertical axis represents the dimensional accuracy in the pattern plane (3σ; unit = μm, solid line), the remaining film ratio (unit =%, dashed line), and the in-plane uniformity of the remaining film thickness (3σ). Unit = angstrom, two-dot chain line), and the horizontal axis represents the developer supply amount f (unit = cc / min) or the developer supply time t (unit = second) in the spray developing method.

Here, the residual film ratio is the ratio of the film thickness before and after dissolution when the resist film is partially treated and dissolved with a developer.

The in-plane uniformity of the remaining film thickness is defined as the variation of the film thickness at each point of the dissolved resist film with a standard deviation σ.
It is expressed in three times.

Further, the dimensional accuracy in the pattern plane refers to the variation in the deviation between the pattern obtained in the case where the pattern is actually formed by exposing and developing the resist by a conventional method and the design pattern. Is expressed as three times the standard deviation σ.

FIG. 8 shows that the tendency of dissolution and the quality of the pattern depend on the resist baking temperature in substantially the same relationship. In other words, when the tendency of dissolution is a desired tendency, for example, when the residual film ratio is the maximum (at the same time, the in-plane uniformity of the residual film thickness is the highest = 3σ is the minimum), the pattern surface The inner dimensional accuracy is the highest (= 3σ is the minimum). Therefore, it can be seen from this relationship that it is possible to obtain the same result and determine the optimum firing conditions only by looking at the tendency of dissolution without actually forming the pattern and measuring the pattern dimensional accuracy. . In addition, since only the tendency of dissolution is observed without exposure, discrimination can be easily performed irrespective of exposure conditions.

Similarly, FIG. 9 shows that the optimum developing conditions can be determined only by looking at the tendency of dissolution.

In the configuration 2, the optimum condition is determined as the desired tendency when the tendency of dissolution is the smallest in the degree of change in the thickness of the resist film before and after the dissolution. The optimum condition is determined when the tendency of dissolution has the highest uniformity of the thickness of the resist film after dissolution as the desired tendency.

In the fourth aspect, the developing conditions for developing and partially dissolving the resist film are set to be smaller than the amount of remaining film or the remaining film ratio which is considered to be appropriate in the developing process for forming the resist pattern. The developing conditions were such that a small residual film amount or residual film ratio was obtained. In other words, the difference in the tendency of dissolution depending on the difference in the firing conditions or the developing conditions was enlarged to increase the identification sensitivity. Things.

According to the configuration 5, it is possible to relatively easily form the resist pattern by obtaining the optimum firing conditions and the optimum developing conditions.

[0028]

FIG. 1 is an explanatory view showing the steps of a method for determining resist forming conditions according to one embodiment of the present invention. As shown in FIG. 1, the method for determining the resist forming conditions according to one embodiment basically includes the following steps.

Step 1: Step of spin-coating a resist on a substrate Step 2: Step of baking the formed resist film Step 3: Measuring at least one of the thickness of the resist film after baking and the uniformity of the film thickness in the substrate Step 4; a step of performing a developer treatment for partially dissolving the resist film with a developer Step 5; at least one of the average film thickness of the resist film after the developer treatment in Step 4 and the uniformity of the film thickness within the substrate However, in step 1, a resist is applied to a plurality of necessary substrates according to the number of firing conditions to be tested. In the step 2, when the firing conditions are determined, the respective resist films are fired under different firing conditions. On the other hand, when determining the developing conditions, each resist film is fired under the same firing conditions.

In step 4, when the firing conditions are determined, each resist film is subjected to a developer treatment under the same developer treatment conditions. On the other hand, when developing conditions are determined, developing processing is performed on each resist film under different developing processing conditions.

A method of forming a resist pattern according to an embodiment of the present invention includes forming a resist pattern by determining a condition by the above-described method for determining a condition of forming a resist pattern, and performing pattern exposure and development using the condition. It is.

Hereinafter, for a positive resist of a type in which an exposed portion is removed by development, an example in which a baking condition is actually determined to form a resist pattern and an example in which a developing condition is actually determined to form a resist pattern Is raised.

(Example of Determining Firing Conditions) First, a photomask production substrate (0.09 inch thick, 5 mm thick) mounted on a turntable.
A plurality of square quartz plates of inch × 5 inches, each having a surface polished and a chrome light-shielding film formed thereon, are prepared as appropriate, and an i-line resist NPR-895i (manufactured by Nagase & Co., Ltd.) solution is discharged to each of them. The film was applied by a spin coating method so that the film thickness after firing was about 5000 Å.

Next, each substrate was placed on a hot plate for 8 hours.
After sintering for 10 minutes at 0 ° C. to 130 ° C. at 6 kinds of sintering temperatures at 10 ° C. each, it was cooled to room temperature by natural cooling in a clean atmosphere.

Next, each of the six types of sample substrates having different sintering temperatures manufactured as described above was subjected to a spectral interference type film thickness measuring device (TM-005 manufactured by CANON) using a method of measuring an optical film thickness from a spectral reflection curve. ) Is used to measure the resist film thickness after firing (44 in the 4.2-inch square region at the center of the substrate).
One point (21 points × 21 points) was performed, and the average film thickness of the resist film before treatment with the developing solution and the standard deviation σ of the resist film thickness were calculated.

Next, each of the sample substrates fired under the respective firing conditions was applied to AZ-400 (Hoe, a stock solution of a developing solution).
chst product name) with a developing solution diluted with a dilution ratio of water: stock solution = 7: 3 by a spray developing method for 90 seconds, followed by rinsing with pure water for 30 seconds and spin-drying. It was left still.

Next, the film thickness is measured for the resist film which has been sufficiently dried after the processing with the developing solution, and similarly, the average film thickness of the resist after the developing solution processing and the standard deviation σ of the resist film thickness are similarly measured. Was calculated.

FIG. 2 is a table showing the results of film thickness measurement before and after the development processing of each sample substrate, and FIG. 3 is a graph showing the values shown in the table of FIG. As shown in FIG. 2 and FIG. In the sample substrate having a firing temperature of 120 ° C., the residual film ratio after the development treatment was the highest, and the film thickness standard deviation value of the residual film was also the smallest. When the sintering temperature is lower than 120 ° C., the residual film ratio after the developing solution treatment decreases as the sintering temperature decreases, and the standard deviation of the residual film thickness increases to improve the uniformity of the residual film. Has been impaired. On the other hand, when the sintering temperature is higher than 120 ° C., the residual film ratio after the development processing is still small, and the film thickness standard deviation value of the residual film is large, and the uniformity of the residual film is impaired. I have.

From the above evaluation results, it was found that the optimum baking temperature of the present resist was 120 ° C.

Next, an argon laser drawing apparatus (exposure wavelength 363.8) was applied to the sample substrate prepared under each firing condition.
nm) by drawing at an exposure dose 40 mJ / cm ^2, which is the undiluted developer solution AZ-Developer (Hoechst Corporation product name), water: concentrate = 1: 60 sec development process with a developing solution which is diluted with dilution ratio of 1 Thus, when a resist pattern was actually formed, the resist pattern on the sample substrate at a firing temperature of 120 ° C. showed a rectangular shape that was almost ideal, and the standard deviation value of a predetermined pattern dimension in the substrate was the smallest. (The dimensional accuracy was the highest).

Here, in the above example, a plurality of firing temperatures were changed as the firing conditions, but this may be changed by changing the firing time. Similarly, the firing method, for example, comparison of firing with a hot air circulating furnace and a hot plate, or all factors related to firing, such as a difference in temperature rise temperature gradient during firing or a difference in cooling temperature gradient after firing. It can be a condition.

(Example of Developing Conditions Determination) A photomask working substrate (0.09 inch thick, 5 inch × 5 inch square quartz plate placed on a turntable is appropriately polished to form a chrome light-shielding film. A plurality of films are prepared, and a solution of i-line resist NPR-895i (manufactured by Nagase & Co., Ltd.) is dropped from a discharge nozzle, and the film thickness after firing is reduced to about 5000 angstroms by a spin coating method. It applied so that it might become.

Next, each substrate was subjected to a baking treatment at a baking temperature of 120 ° C. for 10 minutes using a hot plate, and naturally cooled in a clean atmosphere to room temperature.

A plurality of sample substrates having the same sintering temperature manufactured as described above were used to measure the optical film thickness from the spectral reflection curve by using a spectral interference type film thickness measuring device (TM manufactured by CANON).
-005) to measure the resist film thickness after firing (441 points (21 points × 21 points) in a 4.2-inch square area at the center of the substrate.
Point)), and the average film thickness of the resist before the developer treatment and the standard deviation σ of the resist film thickness were calculated.

Next, another sample substrate fired under the same conditions was applied to AZ-400 (Hoechst) which is a stock solution of a developing solution.
Using a developer diluted at a dilution ratio of water: stock solution = 7.5: 2.5, with developer flow rates of 60 cc / min and 120 cc / min, 180 cc / min and 240 cc / min. Spray development was performed for 60 seconds, 120 seconds and 180 seconds. Thereafter, the substrate was rinsed with pure water for 30 seconds, spin-dried, and allowed to stand.

The resist film thickness of the sufficiently dried resist film was measured in accordance with the above-described film thickness measurement method, and the average film thickness after development and the standard deviation of the resist film thickness were calculated in the same manner.

FIG. 4 is a table showing the results of film thickness measurement before and after the development processing of each sample substrate. FIG. 5 is a graph showing the values of FIG. As shown in FIGS. 4 and 5, in the sample substrate processed at a developing solution flow rate of 240 cc / min, any of the developing conditions were compared with the other developing conditions, that is, the sample substrates processed at 60, 120 and 180 cc / min. As for the time, the residual film ratio after the development processing is low, and the tendency is apparent when the development time is increased. Further, the film thickness uniformity of the residual film after the development processing is clearly inferior.

From the above evaluation results, the optimum developing solution flow rate of the present resist is less than 240 cc / min (180 cc / min or less).
Turned out to be suitable.

4 and 5, when the developing time is 180 seconds, the film thickness uniformity of the residual film after the development is sharper than when the developing time is 120 seconds or less. Is getting worse. In particular, when the flow rate of the developer is 240 cc / min, the tendency is remarkable.

From the above results, it has been found that a developing time of less than 180 seconds (120 seconds or less) is suitable as a developing condition.

The sample substrate prepared under each of the above developing conditions was drawn with an exposure amount of 40 mJ / cm ² by an argon laser drawing apparatus (exposure wavelength: 363.8 nm), and a developing solution AZ-De was used.
When a resist pattern was actually formed by developing with a 1: 1 diluent of Veloper (manufactured by Hoechst) and forming a resist pattern, the resist pattern on the sample substrate processed at a developer flow rate of 60 cc / min showed a rectangular shape closest to the ideal. In addition, the standard deviation value of the predetermined pattern dimension in the substrate was the smallest, and the dimensional accuracy was the highest.

Here, in this example of determining the developing conditions, the developing solution flow rate was changed as the developing conditions.
The type of the developer may be used. Similarly, all the factors relating to development, such as a development method, for example, a comparison between a spray method and an immersion method, can be used as conditions.

In the present invention, the firing conditions and / or the developing conditions are determined by evaluating the remaining film thickness and / or the uniformity of the remaining film thickness in the sample substrate after the development processing by comparing the processed sample substrates. Therefore, arbitrary development conditions can be selected in determining the firing conditions, and arbitrary firing conditions can be selected in determining the development conditions. Also, the method for measuring the film thickness is not particularly limited to the above-described embodiment. Further, by increasing the amount of film reduction due to development as much as possible (decreasing the remaining film ratio as much as possible), that is, for example, by increasing the concentration of the processing developer or lengthening the development time , More detailed investigation is possible.

The firing condition and / or developing condition determination method of the present invention can be applied not only to the positive resist of the above embodiment but also to a polymer resist.

[0055]

As is apparent from the above description, according to the method for determining resist pattern forming conditions of the present invention, a plurality of resist films formed on a substrate are prepared, baked under different firing conditions, and exposed to these. When each of the resist films fired under the respective firing conditions without being subjected to the processing is developed with a predetermined developing solution and partially dissolved, a resist film having a desired tendency of dissolution among the respective resist films. The firing conditions are determined as the resist film firing conditions, and a plurality of resist films formed on the substrate are prepared and fired under predetermined firing conditions, and each of the fired resist films is exposed without subjecting them to exposure treatment. When a part of the resist film is dissolved by developing under different developing conditions, the developing condition is set based on the developing condition of the resist film when the dissolution tendency of each resist film shows a desired tendency. The method for determining a resist pattern formation condition can be easily determined in a small number of steps independently of each other, independently of the amount of electromagnetic wave irradiation, and independently of the baking condition or developing condition of the resist film. And a method of forming a resist pattern in which a resist pattern is formed under the conditions determined by the method for determining conditions for forming a resist pattern.

[Brief description of the drawings]

FIG. 1 is a process explanatory diagram of a method for determining resist forming conditions according to one embodiment of the present invention.

FIG. 2 is a table showing measurement results of an average resist film thickness before and after a developer treatment of each sample substrate, and a calculation result of a standard deviation value of the resist film thickness and a residual film ratio.

FIG. 3 is a graph showing the values shown in the table of FIG. 2;

FIG. 4 is a table showing measurement results of an average resist thickness before and after a developer treatment of each sample substrate, and a calculation result of a standard deviation value of the resist film thickness and a residual film ratio.

FIG. 5 is a graph showing the values shown in the table of FIG. 4;

FIG. 6 is an explanatory diagram of a conventional method for determining optimum firing conditions.

FIG. 7 is an explanatory diagram of a conventional method for determining optimum developing conditions.

FIG. 8 is a graph showing the relationship between the resist baking temperature T, the tendency of dissolving the resist film (in-plane uniformity of the remaining film ratio and the remaining film thickness), and the quality of the pattern (in-plane pattern dimensional accuracy).

FIG. 9 shows resist development conditions (developer supply amount f or developer supply time t), dissolution tendency of the resist film (residual film ratio and in-plane uniformity of residual film thickness), and pattern quality (in-plane pattern). 6 is a graph showing a relationship with the dimensional accuracy.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-103053 (JP, A) JP-A-4-142728 (JP, A) JP-A-4-93014 (JP, A) JP-A-54- 150079 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01L 21/027

Claims (5)

(57) [Claims] A resist film forming step of forming a resist film on a substrate; a resist film firing step of firing the resist film formed by the resist film forming step; and a resist film fired by the resist film firing step Exposure step of performing a predetermined pattern exposure by electromagnetic waves or particle beams, and either one of the resist film baking conditions and development conditions in the resist pattern forming step having a development step of performing development processing on the resist film after this exposure step or A resist pattern forming condition determining method for determining processing conditions for both processes, wherein a plurality of resist films formed on a substrate are prepared and fired under different firing conditions, and each of the firing conditions is performed without performing an exposure process. Each of the resist films baked in the step is subjected to a developing solution treatment for partially dissolving the resist film under a predetermined developing solution and processing conditions. Then, among the resist films, the firing conditions of the resist film having the desired tendency of dissolution are determined as the firing conditions of the resist film, and a plurality of resist films formed on the substrate are prepared and fired at a predetermined firing temperature. When each of the baked resist films is subjected to developing solution treatment under different developing solution processing conditions and partially dissolved without subjecting them to exposure treatment, the tendency of dissolution of each of the resist films is desired. A method for determining a resist pattern forming condition, comprising: determining a developing condition based on a developing solution processing condition of a resist film when the tendency is exhibited. 2. The resist pattern forming condition determining method according to claim 1, wherein the tendency of the dissolution is the desired tendency when the degree of change in the thickness of the resist film before and after the dissolution is smallest. Method for determining conditions for forming resist patterns. 3. The method for determining conditions for forming a resist pattern according to claim 1, wherein the tendency of the dissolution is the desired tendency when the uniformity of the thickness of the resist film after dissolution is highest. Method for determining conditions for forming resist patterns. 4. The method for determining conditions for forming a resist pattern according to claim 1, wherein the processing conditions of the developing solution when the resist film is subjected to a developing solution process and partially dissolved are determined by forming a resist pattern. A process for obtaining a residual film amount or a residual film ratio smaller than an appropriate residual film amount or residual film ratio in a developing process when the resist pattern is formed. 5. A resist film forming step for forming a resist film on a substrate, a resist film firing step for firing the resist film formed in the resist film forming step, and a resist film fired in the resist film firing step In a resist pattern forming method having an exposure step of performing a predetermined pattern exposure by electromagnetic waves or particle beams and a development step of performing a development process on the resist film after the exposure step, the resist film baking conditions in the resist film baking step and 5. A method for forming a resist pattern, wherein a condition determined by the method for determining a condition for forming a resist pattern according to claim 1 is used as a developing condition in the developing step.