JPH0532898B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention provides a pattern position accuracy diagnosis method for diagnosing the position accuracy of a pattern drawn on a resist film formed on a conductive substrate, and Regarding equipment.

(Prior Art) Conventionally, as a method for diagnosing the positional accuracy of a pattern drawn on a resist film formed on a conductive substrate, a pattern position accuracy mark is formed on the resist film outside the main pattern area. , a method of determining the amount of deviation using a microscope, etc.
11461) is known.

(Problems to be Solved by the Invention) In such conventional methods, not only can the positional accuracy of the pattern be determined only after the pattern is formed, that is, after it has been drawn and developed, but it is also difficult for humans to use a microscope. It is necessary to measure the position accuracy mark using a conventional method, which poses the problem that defective products cannot be detected early.

The present invention has been made in consideration of the above problems, and it is an object of the present invention to provide a method and apparatus for diagnosing pattern position accuracy that can quickly diagnose the quality of a drawn pattern.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a pattern position accuracy diagnosis method for diagnosing the position accuracy of a pattern formed on a resist film laminated on a conductive substrate, in which a pattern is drawn on the resist film. Beforehand, there is a step of drawing a first positional accuracy monitor pattern on the resist film in an area other than the area where the pattern is drawn, and a step of drawing a first positional accuracy monitor pattern on the resist film after the pattern is drawn on the resist film, if there is a positional shift in the pattern. a step of drawing a second positional accuracy monitor pattern in which a portion overlaps with the first positional accuracy monitor pattern; a step of immersing the conductive substrate on which the first and second positional accuracy monitor patterns are drawn in a developer; The method is characterized by the step of immersing the electrode in a developer and determining the amount of positional shift of the pattern based on the current flowing between the electrode and the conductive substrate.

The present invention provides a pattern position accuracy diagnosis device for diagnosing the positional accuracy of a pattern drawn on a resist film formed on a conductive substrate, in which a pattern is drawn on a region where the pattern is drawn before the pattern is drawn on the resist film. a means for drawing a first positional accuracy monitor pattern on a resist film in an area other than that of the resist film, and a portion that overlaps with the first positional accuracy monitor pattern when there is a positional shift in the pattern after the pattern is drawn on the resist film; a means for drawing a second positional accuracy monitor pattern in which a second positional accuracy monitor pattern is generated; a conductive substrate on which the first and second positional accuracy monitor patterns are drawn are immersed in a developer; and an electrode is immersed in the developer; and means for determining the amount of positional deviation of the pattern based on the current flowing between the conductive substrate and the conductive substrate.

(Function) According to the method for diagnosing pattern position accuracy according to the present invention configured as described above, before a pattern is written, the first position accuracy monitor is placed on the resist film in an area other than the area where the pattern is written. A pattern is drawn. Further, after the pattern is drawn, a second positional accuracy monitor pattern is drawn, in which a portion overlaps with the first positional accuracy monitor pattern when there is a positional shift in this pattern. Then, the conductive substrate on which the first and second positional accuracy monitor patterns are drawn is immersed in a developer, and the pattern is drawn based on the current flowing between the conductive substrate and the electrode immersed in the developer. The amount of positional deviation is determined. Thereby, the quality of the drawn pattern can be diagnosed before the pattern is developed.

Further, according to the pattern position accuracy diagnosis apparatus according to the present invention configured as described above, the conductor substrate on which the first and second position accuracy monitor patterns are drawn is immersed in a developer solution, and the conductor substrate is The amount of pattern position shift is determined based on the current flowing between the electrode and the electrode immersed in the developer. Thereby, the quality of the drawn pattern can be diagnosed before the pattern is developed.

(Example) Embodiments of the present invention will be described using the drawings.

The steps of an embodiment of the method for diagnosing pattern position accuracy according to the present invention are shown in the flowchart of FIG. In the pattern position accuracy diagnosis method of this embodiment, first, in step F1, a resist is applied onto a conductive substrate to form a resist film.

Next, in step F2, before a predetermined pattern (hereinafter referred to as main pattern) 2 is drawn on the conductive substrate 1 on which the resist film is formed, for example, in an area other than the area where this main pattern 2 is drawn, A first position accuracy monitor pattern 3A shown in FIG. 2b is drawn (see FIG. 2a). In addition,
First positional accuracy monitor pattern 3 shown in FIG. 2b
A consists of patterns (shaded areas) that are long in the vertical direction (y direction) and arranged at a pitch of 2 μm in the horizontal direction (x direction), and are used to find the amount of deviation in the x direction.

In step F3, main pattern 2 is drawn, and then in step F4, for example, the first pattern is drawn.
A second positional accuracy monitor pattern 3B (see FIG. 2c) having the same shape as the positional accuracy monitor pattern 3A,
The first positional accuracy monitor pattern 3A is drawn at a position shifted in the x direction by 2 μm from the drawn position. At this time, if the main pattern has no positional deviation in the x direction, the first positional accuracy monitor pattern 3A and the second positional accuracy monitor pattern 3B will not overlap, but if the main pattern has a positional deviation in the x direction The first positional accuracy monitor pattern 3A and the second positional accuracy monitor pattern 3B overlap by this amount of positional deviation. The exposure amount of this overlapping portion is higher than that of other portions.

Next, in step F5, only the portions where the first and second position accuracy monitor patterns 3A and 3B are drawn are immersed in a developer 7 for selectively removing the resist, as shown in FIG. Then, in step F6, an electrode 8 made of, for example, platinum (Pt) or silver-silver chloride (AgAgCl), which is stable in the developer 7, is immersed in the developer 7, and an electrode 8 is placed between the electrode 8 and the conductive substrate 1. Amplifier 9
(see FIG. 3), and based on this detected current value, the amount of positional deviation of the main pattern is determined by, for example, the determining circuit 10 shown in FIG. 3.

Next, a method for determining the amount of positional deviation will be explained. FIG. 4 shows how the current flowing between the conductive substrate 1 and the electrode 8 changes. Graph A (solid line) shows the change in current when the first and second positional accuracy monitor patterns do not overlap, that is, when there is no positional deviation in main pattern 2, and graph B (broken line) shows the change in current when the first and second positional accuracy monitor patterns do not overlap, that is, when there is no positional deviation in main pattern 2. 2 shows the change in current when the position accuracy monitor patterns No. 2 overlap by 0.5 μm, that is, when a positional deviation of 0.5 μm occurs in the main pattern 2. The time _tB1 for the current to rise when there is misalignment in the main pattern and the time _tA1 for the current to rise when there is no misalignment are in the relationship _tB1 < _tA1 . be. This is because if a positional shift occurs, there will be an overlapping portion between the first and second position accuracy monitor patterns 3A and 3B, and the exposure amount of this overlapping portion will be higher than the exposure amount of other portions.

Also, the relationship between the time t _B2 when the current rises until it reaches its peak when there is a position shift and the time t _A2 when there is no position shift is t _A2
<t _B2 . The ratio of these times, i.e., α=t _B1 /t _A1 and β=t _B2 /t _A2 , will change depending on the amount of positional deviation if the temperature of the developer 7, the exposure amount during drawing, etc. are the same. . Therefore, by measuring the time t _A1 , t _B1 until the current rises or the time t A2 , t _B2 from the time the current rises to the peak, the amount _of positional deviation can be determined.

Although this embodiment has explained the positional deviation in the x direction, if the first and second positional accuracy monitor patterns 3A and 3B are rotated 90 degrees and a positional deviation occurs, the first and second positional accuracy If the monitor patterns are drawn so that they overlap, the amount of positional deviation in the y direction can be determined in the same way as in the x direction.

As described above, according to the present embodiment, the quality of the pattern can be diagnosed before the main pattern 2 is formed (development is completed), and through cost can thereby be reduced.

Note that the first and second positional accuracy monitor patterns have the same effect as the above embodiment even if they overlap when a positional deviation greater than the positional deviation error determined for each product occurs. The first position accuracy monitor pattern and the second
Even if the positional accuracy monitor patterns are inversely related to each other, the same effects as in the above embodiment can be obtained.

In addition, in the above embodiment, only the portions where the first and second positional accuracy monitor patterns were drawn were immersed in the developer, but the exposure amount for drawing the first and second positional accuracy monitor patterns was changed to that of the main pattern 2. The entire conductive substrate on which the first and second positional accuracy monitor patterns and the main pattern have been drawn is immersed in a developer at a higher exposure dose (for example, twice or more) than the exposure amount for drawing, and the area between the conductive substrate and the electrode is immersed in a developer. The quality of the pattern can be determined based on the current flowing through the pattern in the same manner as in the above embodiment. FIG. 5 shows the current flowing between the conductive substrate and the electrode in this case. In FIG. 5, a graph C shown by a solid line shows the change in current when no positional deviation occurs, and a graph D shown by a broken line shows a change in current when there is a positional deviation. Note that the arc at time T is due to completion of development of the main pattern.

Further, the pattern position accuracy diagnostic device according to the present invention includes pattern drawing means and positional deviation amount determining means. This pattern drawing means applies a first position accuracy monitor pattern (for example,
The pattern shown in FIG. 2a), the main pattern, and the second positional accuracy monitor pattern (for example, the pattern shown in FIG. 2b) are used for drawing. The order in which these patterns are drawn is that first the first position accuracy monitor pattern is drawn in an area other than the area where the main pattern is drawn, and then the main pattern is drawn. Thereafter, a second positional accuracy monitor pattern is drawn in which a portion overlaps with the first positional accuracy monitor pattern when there is a positional shift in the main pattern.

The positional deviation amount determining means immerses the conductive substrate on which the first and second positional accuracy monitor patterns are drawn in a developer that selectively removes the exposed resist, and removes the immersed conductive substrate. The amount of positional shift of the main pattern is determined based on the current flowing between the electrode and the electrode immersed in the developer (see FIG. 3).

The quality of the drawn main pattern can also be diagnosed at an early stage using this pattern position accuracy diagnostic device.

〔Effect of the invention〕

According to the present invention, it is possible to diagnose the quality of a pattern at an early stage, thereby reducing through cost.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the steps of an embodiment of the method for diagnosing pattern position accuracy according to the present invention, FIG. 2 is a diagram showing the first and second position accuracy monitor patterns and their arrangement, and FIG. 3 is a diagram showing the conductive substrate and A block diagram showing a device for measuring the current flowing between the electrodes,
4 and 5 are graphs showing changes in current when measured using the apparatus shown in FIG. 3. 1...A conductive substrate on which a resist film is formed, 2
...Main pattern, 3A, 3B...Position accuracy monitor pattern, 7...Developer, 8...Electrode, 9...
...Amplifier, 10...Judgment circuit.

Claims (1)

[Claims] 1. In a pattern position accuracy diagnosis method for diagnosing the positional accuracy of a pattern drawn on a resist film formed on a conductive substrate, before drawing the pattern on the resist film,
a step of drawing a first positional accuracy monitor pattern on the resist film in an area other than the area where the pattern is drawn, and after the pattern is drawn on the resist film,
drawing a second positional accuracy monitor pattern in which a portion overlaps with the first positional accuracy monitor pattern when the pattern has a positional deviation; and the first and second positional accuracy monitor patterns are drawn. a step of immersing the conductive substrate in a developer; a step of immersing an electrode in the developer and determining an amount of positional shift of the pattern based on a current flowing between the electrode and the conductive substrate; A method for diagnosing pattern position accuracy, comprising: 2. In a pattern position accuracy diagnostic device for diagnosing the positional accuracy of a pattern drawn on a resist film formed on a conductive substrate, before drawing the pattern on the resist film,
means for drawing a first positional accuracy monitor pattern on a resist film in an area other than the area where the pattern is drawn; after the pattern is drawn on the resist film;
means for drawing a second positional accuracy monitor pattern in which a portion overlaps with the first positional accuracy monitor pattern when the pattern has a positional deviation; and the first and second positional accuracy monitor patterns are drawn. means for immersing the conductive substrate in a developer solution and immersing an electrode in the developer solution, and determining the amount of positional shift of the pattern based on the current flowing between the electrode and the conductor substrate; A pattern position accuracy diagnostic device comprising: