JPH0582425A - Drawing data conversion method - Google Patents

Abstract

(57) [Abstract] [Purpose] Converting from the plotter code output from the CAD system to the drawing data for drawing with the electron beam without being restricted by the size of the board and the size and type of the wiring pattern. The purpose is to do. [Structure] As it is, it has a substitution processing function of replacing a pattern that cannot be drawn with a linear pattern and a land pattern, and a division processing function of dividing a pattern exceeding the maximum deflection range of an electron beam at a field connecting portion. It consists of a procedure of effectively combining the functions and converting the photoplotter code output from the CAD system into a pattern for drawing with an electron beam. [Effect] The drawing data for the electron beam drawing apparatus can be obtained from the conventionally existing photoplotter data with a minimum required capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an algorithm for converting a wiring pattern of a printed circuit board or the like into drawing data when drawing with an electron beam, that is, a drawing data conversion method.

[0002]

2. Description of the Related Art In recent years, a photomask or an electron beam drawing apparatus for drawing a pattern on the surface of a wafer with an electron beam has been used to draw a pattern in a narrow area such as a semiconductor integrated circuit.

This type of electron beam drawing method is shown in FIG.
This will be described with reference to FIGS. 12 and 1
FIG. 3 is a diagram showing a conventional electron beam drawing method disclosed in, for example, Japanese Patent Laid-Open No. 2-299220.

FIG. 12 is a diagram showing electron beam drawing pattern data. A rectangular frame 1 surrounded by a solid line is a drawing pattern data area. An area shaded by an alternate long and short dash line and shaded is a deflection range 2 of the electron beam. In this area 2, the pattern is drawn only by the deflection of the beam without moving the table of the drawing apparatus. The above-mentioned alternate long and short dash line is a connecting portion 4 of the fields 3a and 3b, and 5 is a pattern extending over this.

FIG. 13 (a) is an enlarged view of the main part of the drawing pattern data. The patterns 6 and 7 are connected to the inside of the fields 3a and 3b, and the connection between the fields 3a and 3b drawn with alternate long and short dash lines. There is a pattern 5 that spans the portion 4.

Next, the electron beam writing method of the above-mentioned conventional example will be described. As shown in FIG. 13B, when the left field 3a is drawn, the pattern 6 in this area and the pattern 5 extending over the connecting portion 4 are drawn by deflection without being cut.

Further, as shown in FIG. 13C, the right field 3b is also drawn by deflection without cutting the pattern 7 and the pattern 5 extending over the connecting portion 4. Then, the pattern 5 straddling the connecting portion 4 was performed with a dose amount of 1/2.

[0008]

The conventional electron beam writing method as described above is effective when writing in a narrow area such as a semiconductor integrated circuit. Therefore, writing data for realizing this method is created. The algorithm to do is
In the case of drawing on a wide area such as a printed circuit board, there is a problem that it cannot be applied because there are patterns that exceed the deflectable range of the beam. Further, since the patterns are overwritten, when drawing in a wide area, there is a problem that the amount of data that greatly affects the throughput increases and the dose amount must be controlled.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to draw on a wide area such as a printed circuit board, the drawing pattern can be suppressed to the minimum necessary increase amount, and the dose amount can be reduced. It is an object of the present invention to obtain a drawing data conversion method for realizing an electron beam drawing method that does not need to be controlled.

[0010]

A drawing data conversion method according to the present invention includes the following processes. [1] A division process in which when the wiring pattern extends over a plurality of fields, the wiring pattern is divided at the connecting portions of the fields to form a pattern that can be drawn for each field. [2] The distance between the field and the electron beam maximum deflection area set outside the field is (the wiring pattern /
Replacement processing for replacing a wiring pattern that cannot be drawn when the length is smaller than the length of 2) or when the electron beam drawing apparatus does not have a drawing function by approximating the wiring pattern with a linear pattern and a land pattern.

[0011]

According to the present invention, when the wiring pattern extends over a plurality of fields, the wiring pattern is divided at the connecting portions of the fields by the division processing so that each field can be drawn. Also,
When the distance between the field and the electron beam maximum deflection area set outside the field is smaller than the length of (wiring pattern / 2) by the replacement processing, and the electron beam drawing apparatus does not have a drawing function. The wiring pattern that cannot be drawn in the case of the wiring pattern is approximated and replaced by the straight line pattern and the land pattern.

[0012]

EXAMPLES Example 1. The processing of the linear pattern (the linear wiring pattern extending over a plurality of fields) according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2 are diagrams showing a dividing process of a linear pattern according to the first embodiment of the present invention. In the drawings, the same reference numerals indicate the same or corresponding parts.

In FIG. 1, the straight line pattern has a starting point (x
The pattern is wired from (s, ys) to the end point (xe, ye), and the dotted line is a straight line passing above the two points. The intersections of this straight line and the connecting portion 4 of the field are 8, 9, 10, and 11. The length of one side of the field is L, and the field surrounded by the connecting portion of the Nth and N + 1th fields in the x direction and the connecting portion of the Mth and M + 1th fields in the y direction is the NM field.

A method of dividing a straight line pattern whose starting point exists in the NM field will be described. First, the equation of a straight line passing through the start point and the end point of the straight line pattern is obtained. Next, the intersection points 8, 9, 10 of this straight line and the connecting portion of the four fields
Ask for 11. Of these four intersections, the intersections existing between the coordinates of the start point and the end point (both x and y) are obtained. However, when there are a plurality of intersections that satisfy the conditions, the one closer to the start point side is selected.

The drawing data of the NM field extends from the starting point to this intersection, the straight line data is divided at this position, and this intersection is adopted as a new starting point. N and M depending on the junction of the fields intersecting the selected intersection
Increase or decrease the value of to determine the position of the next field. This process is repeated until the end point matches the existing field. At the time of coincidence, division is completed by using the pattern from the last selected intersection to the end point as the drawing data of the field in which the end point exists.

The method of increasing and decreasing N and M is as follows. First, as shown in FIG. 1, when an intersection with the connecting portion of the Mth field is adopted, the field that constructs the next divided pattern is N (M -1) It is a field.

In other cases, as shown in FIG. 2 (a), M +
When the intersection with the connecting portion of the first field is adopted, the next field is set to the N (M + 1) field. Further, as shown in FIG. 2B, when the intersection with the connecting portion of the Nth field is adopted, the next field is defined as (N-1) M field. Furthermore, FIG.
As shown in (c), when the intersection of the N + 1th field and the connecting portion is adopted, the next field is (N
+1) M fields.

For example, in the case of FIG. 1, the straight line pattern is divided at the intersection points 10, and the pattern from the start point to the intersection points 10 is NM.
The drawing data of the field is used, and the pattern from the intersection 10 to the end point is used as the drawing data of the N (M-1) field. Further, in the above case, the division is performed from the intersection closer to the start point, but the division may be performed from the intersection closer to the end point with the end point as a reference.

Next, processing of the land pattern (wiring pattern in which the inside of a circle or a square is filled) of the first embodiment will be described with reference to FIG. FIG. 3 is a diagram showing a land pattern replacement process according to the first embodiment of the present invention.

In the land pattern 12 shown in FIG. 3A, the length of 1/2 of the pattern size is smaller than {(electron beam maximum deflection area 13)-(field connecting portion 4)}. Therefore, draw in the field where the center exists. In this case, the drawing data of the NM field is used.

However, the land pattern 14 shown in FIG.
In the case of, the allowable range {(electron beam maximum deflection area 13)
-(Field connecting part 4)} exceeds 1/2 of the pattern size, and therefore cannot be drawn as it is.

Therefore, as shown in FIG. 3B, the land pattern 14 is approximated by a linear pattern, and the pattern is divided at the connecting portion of the field. The pattern drawn in the NM field is the divided pattern group 15 on the NM field, while (N + 1) M
The pattern drawn in the field is (N +
1) A pattern group 16 on the M field.

Further, in the case of an arc pattern (arc-shaped wiring pattern), approximation is performed by a straight line pattern or a land pattern, and the pattern is replaced. Then, the pattern is divided into two fields to determine the field to be drawn.

FIG. 4 shows a case of approximating with a straight line pattern. When the circular arc pattern 17 shown in FIG. 4A is approximated with a straight line, it becomes as shown in FIG. When the pattern 18 extending over two fields is divided at the field connecting portion 4, it becomes as shown in FIG. The pattern on the NM field and the divided pattern 18a are the drawing data of the NM field, and the pattern 19 on the (N + 1) M field and the divided pattern 18b are (N +
1) M-field drawing data.

FIG. 5 shows an example of a linear pattern that exceeds the allowable range. In FIG. 5A, the linear pattern 2
In the case of 1, the drawing can be performed in the NM field having the start point and the end point, but in the case of the straight line pattern 20, the drawing cannot be performed because the length of (line width of the pattern) / 2 exceeds the allowable range. Therefore, as shown in FIG. 7B, the straight line pattern 20 is replaced with a combination of straight line patterns having a length of (pattern line width) / 2 within an allowable range.

That is, at the start point and the end point, the straight line pattern 2
By setting the land pattern having the diameter equal to the line width of 0, a land pattern having a diameter equal to the line width of the straight line pattern 20 creates a locus formed by moving while drawing from the start point to the end point. After such replacement processing is completed, the replacement pattern is divided at the connecting portion 4 of the field. Thus, the drawing data finally created is, as shown in FIG. 5B, the land pattern 22 and the straight line pattern 24 in the NM field, and the land pattern 23 and the straight line pattern 25 in the (N + 1) M field. ..

Incidentally, as shown in FIG. 6, it is possible to replace all with the linear patterns 26 and 27 without using the land pattern.

Here, the operation of the above-described first embodiment, that is, the process combining all of the above processes will be described with reference to FIGS.
The description will be made with reference to items 1 to 1. 7 to 9
It is a flow chart which shows the main processing of Example 1 of this invention. 10 and 11 are flowcharts showing the replacement process and the division process in the main process.

First, the main processing will be described with reference to FIGS.
It will be explained with reference to. Schematically, FIGS. 7, 8 and 9 show the processing of straight line patterns, land patterns and arc patterns, respectively.

In step 30 of FIG. 7, it is judged whether or not the pattern is a straight line pattern.
No. 38, and if it is a straight line pattern, the process proceeds to the next Step 31. In steps 31 and 32,
It is judged whether or not the replacement process is necessary, that is, both the connecting portion of the field and the maximum deflection area of the electron beam: (pattern size / 2) are compared, and if they are not equal, the process proceeds to step 33, and if they are equal, Performs the replacement process in step 32.

In steps 33 and 34, it is judged whether or not the division processing is necessary, that is, both the field having the start point and the field having the end point are compared,
If they are not equal, the process proceeds to step 36, and if they are equal, the division process is performed in step 34. Step 35
In the case of the wiring pattern data of the NM field, the process returns to step 33.

In steps 36 and 37, the wiring pattern data of the NM field is obtained, and the wiring pattern data of each field is converted into the drawing data for the electron beam drawing apparatus. Then, a series of processing is ended.

In step 38 of FIG. 8, it is determined whether or not it is a land pattern. If it is not a land pattern, the process proceeds to step 44, and if it is a land pattern, the process proceeds to the next step 39. In steps 39 and 40, it is determined whether or not the replacement process is necessary, that is, the joint portion of the field and the maximum deflection area of the electron beam:
Both (pattern size / 2) are compared, and if they are not equal, the process proceeds to step 36 in FIG. 7, and if they are equal, the replacement process is performed at step 40.

In steps 41 and 42, it is judged whether or not the division processing is necessary, that is, both the field having a start point and the field having an end point are compared,
If they are not equal, the process proceeds to step 36 in FIG. 7, and if they are equal, the division process is performed in step 42. In step 43, the wiring pattern data of the NM field is set, and the process returns to step 41.

In step 44 of FIG. 9, it is determined whether or not it is an arc pattern. If it is not an arc pattern, the process proceeds to step 50, and if it is an arc pattern, the process proceeds to the next step 45. In steps 45 and 46, it is judged whether or not the replacement process is necessary, that is, both the joint portion of the field and the maximum deflection area of the electron beam: (pattern size / 2) are compared, and if they are not equal, step 47 is performed. If it is equal, the substitution process is performed in step 46.

In steps 47 and 48, it is judged whether or not the division processing is necessary, that is, both the field having the start point and the field having the end point are compared,
If they are not equal, the process proceeds to step 36 in FIG. 7, and if they are equal, the division process is performed in step 48. In step 49, the wiring pattern data of the NM field is set, and the process returns to step 47. In step 50,
The pattern size is set and the process ends.

Next, the replacement process will be described. In step 60 of FIG. 10, the field addresses N and M where the starting point exists are obtained.

In step 61, the field addresses L and K where the end points exist are obtained. Steps 62 and 63
In N, it is determined whether or not the field address N = L and M = K. If N = L and M = K, the process proceeds to step 68. If not, the start point and end point are determined in step 63. Find the equation of a straight line passing through.

At step 64, the obtained straight line and L
The intersections with the four field connecting portions of × N, L × (N + 1), L × M, L × (M + 1) are obtained. Step 6
In step 5, the intersection A closest to the obtained intersection is selected.

At step 66, at the starting point and the intersection point A,
The wiring pattern is divided into wiring patterns for the NM field. In step 67, the value of N and M is increased / decreased depending on which field connecting portion the intersection A is the starting point, and the process returns to step 62.

In step 68, the wiring pattern from the start point to the end point is set as the wiring pattern of the NM field,
The process ends.

Further, the dividing process will be described. Figure 1
In steps 70 and 71 of step 1, it is determined whether or not the pattern is a straight line pattern.
If it is a straight line pattern, in step 71, a specific straight line pattern is selected and replaced from the coordinates of the start point and end point and the line width. Then, the process ends.

In steps 72 and 73, it is judged whether or not it is a land pattern. If it is not a land pattern, the process proceeds to step 74, and if it is a land pattern, in step 73 the minimum line width is determined from the center coordinates and the diameter. The start point and the end point are determined and replaced so as to approximate the circumference of the circle with a straight line pattern. Then, the process ends.

In step 74, a specific straight line pattern is selected and replaced according to the end point coordinates, the distance from the start point to the center, and the line width. Then, the process ends.

The first embodiment of the present invention, as described above,
In the procedure of converting the wiring pattern into the drawing data, a wiring pattern that can be drawn with an electron beam is formed by a combination of division processing and replacement processing, and then the wiring pattern is constructed for each field. After this processing is completed, the wiring pattern is converted into drawing data for the electron beam drawing apparatus for each field.

In the above replacement process, a pattern that cannot be drawn as it is due to the size or shape of the wiring pattern is replaced with a combination of drawable wiring patterns.
Further, the division processing is a linear wiring pattern that extends over a plurality of fields, and when it is at a position beyond the deflection range of the electron beam, it is divided at the connecting portion of the fields. By performing the replacement process and the division process on the photo plotter code (wiring pattern) output from the CAD system, a wiring pattern that can be drawn by the electron beam drawing apparatus is obtained. The wiring pattern is constructed for each field, and after the work is completed, it is converted into drawing data for the electron beam drawing apparatus.

In the first embodiment of the present invention, the wiring pattern that can be drawn by the electron beam drawing apparatus is obtained by performing the replacement process and the division process on the photoplotter data (wiring pattern) output from the CAD system. Since it can be converted into, the drawing data for the electron beam drawing apparatus can be obtained. Furthermore, since the wiring pattern obtained after the replacement processing and the division processing is the minimum necessary wiring pattern, it is possible to minimize the influence of the capacity after the conversion into the drawing data for the electron beam drawing apparatus on the throughput. Has the effect.

The first embodiment of the present invention is not restricted by the size of the board and the size and type of the wiring pattern, and the code for the photo plotter output from the CAD system
The purpose is to convert into drawing data for drawing with an electron beam. As it is, it has a replacement processing function to replace a pattern that cannot be drawn with a straight line pattern and a land pattern, and a division processing function to divide the pattern exceeding the maximum deflection range of the electron beam at the field connecting portion, and these functions are effective. Are combined with each other to convert the photo plotter code output from the CAD system into a pattern for drawing with an electron beam. From the existing photo plotter data,
Drawing data for the electron beam drawing apparatus can be obtained with the minimum required capacity.

[0049]

As described above, according to the present invention, when the wiring pattern extends over a plurality of fields, the wiring pattern is divided at the connecting portions of the fields, and the division processing is performed so that the pattern can be drawn for each field. ,
When the distance between the field and the electron beam maximum deflection area set outside the field is smaller than the length of (wiring pattern / 2), and when the electron beam drawing apparatus does not have a drawing function. Since a wiring pattern that cannot be drawn on the line is replaced by approximating it with a linear pattern and a land pattern, it is possible to minimize the effect on the throughput due to the capacity after conversion into drawing data for the electron beam drawing apparatus. There is an effect that can be.

[Brief description of drawings]

FIG. 1 is a diagram showing a dividing process of a linear pattern according to a first embodiment of the present invention.

FIG. 2 is a diagram showing how a linear pattern and a field connecting portion of the first embodiment of the present invention intersect with each other.

FIG. 3 is a diagram showing processing of a land pattern according to the first embodiment of the present invention.

FIG. 4 is a diagram showing processing of an arc pattern according to the first embodiment of the present invention.

FIG. 5 is a diagram showing processing of a linear pattern that requires division according to the first embodiment of the present invention.

FIG. 6 is a diagram showing another process of a linear pattern that requires division according to the first embodiment of the present invention.

FIG. 7 is a flow chart showing main processing of Embodiment 1 of the present invention.

FIG. 8 is a flowchart showing main processing of the first embodiment of the present invention.

FIG. 9 is a flowchart showing main processing of the first embodiment of the present invention.

FIG. 10 is a flowchart showing a replacement process according to the first embodiment of the present invention.

FIG. 11 is a flowchart showing a dividing process according to the first embodiment of the present invention.

FIG. 12 is a diagram showing a conventional drawing method.

FIG. 13 is a diagram showing a conventional drawing method.

[Explanation of symbols]

 4 Field connection 13 Electron beam maximum deflection area 14 Land pattern 17 Arc pattern 20 Linear pattern

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shoji Kamio 8-1-1 Tsukaguchihonmachi, Amagasaki City Mitsubishi Electric Corporation Itami Works

Claims (1)

[Claims] 1. When the wiring pattern extends over a plurality of fields, the wiring pattern is divided at the connecting portions of the fields so as to form a pattern that can be drawn for each field, and the field and the outside thereof are set. If the distance between the maximum deflection regions of the electron beam is smaller than the length of (wiring pattern / 2), or if the electron beam drawing device does not have a drawing function, a wiring pattern that cannot be drawn is a straight line pattern. And a land pattern are approximated and replaced, and a drawing data conversion method is included.