CN101334812A - Method for cutting CIF format circle into PG3600 format rectangle - Google Patents

Abstract

The invention relates to the technical field of microlithographic data format conversion, and discloses a method for cutting a CIF format circle into a PG3600 format rectangle, which comprises the following steps: taking the circular approximation as a regular n-polygon, and calculating the value of n, wherein n is a natural number; cutting the regular n-sided polygon into a combination of rectangles and right triangles; combining the cut rectangles into a rectangle to the maximum extent; combining the rectangles of the left and right parts outside the rectangles obtained after combination into rectangular strips in the vertical direction, and combining the rectangles of the upper and lower parts outside the rectangles obtained after combination into rectangular strips in the horizontal direction; for the right triangle obtained by cutting, the hypotenuse of the right triangle is taken as one side of the rectangle to make a rectangle to surround the right triangle. The cutting method is simple and easy to program, the error between the cut graph and the original graph is small, and the cut rectangle data volume is small.

Description

The CIF format circular is cut into the method for PG3600 format rectangle

Technical field

The present invention relates to micro-lithography graphics data format switch technology field, relate in particular to a kind of method that the CIF format circular is cut into the PG3600 format rectangle.

Background technology

Because different exposure sources generally all is to use own special-purpose graphics data format, handle so must carry out Data Format Transform.Remain many optical exposure systems at present and remain GCA 3600F pattern generator (GCA 3600F Pattern Generator) and GCA 3696 substeps and repeat final reaction system (GCA 3696 Photo-Repeater), the PG3600 graphics data format that it uses (PG3600 format) is stored data with the rectangle of different angles as elementary cell.

Form (the Caltech Intermediate Form of California intermediary of the Institute of Technology, CIF) be one of commonly used data interchange format of photomask manufacturing industry in the world, it is with circle, circle, rectangle and four kinds of figures such as line segment of width are arranged is fundamental figure unit storage data.Because it is to write with textual form, be convenient to revise and editor, so in graphic processing data and format conversion process, use it always as intermediate form.

The method that traditional CIF format circular cuts into the PG3600 format rectangle is that string and the radius of a circle with certain angle correspondence is the length of side of rectangle, and according to this angle rotation exposure, circular central is a large amount of overlapping exposures, has a strong impact on the quality of mask.Also the someone adopts other cutting methods to replace tradition rotation cutting mode, and as the bar shaped patterning method etc., but the rectangle number that cuts off out is too many and the edge is irregular.

For this reason, we also adopt the data-switching mode from CIF to the PG3600 form.At first, allowing under a small amount of overlapping situation of figure, the various pattern cut in the CIF form are being become the rectangle of the needed various angles of PG3600, and then requiring to carry out code conversion according to optical figuring generator 3600F computing machine exposure control language.

Principal character of the present invention is the rectangle that the circle in the CIF form is cut into the PG3600 form under the condition that error allows, and the rectangle lap that it is cut out is littler much than other cutting methods, and the rectangle data amount that cuts out is also few.

Summary of the invention

(1) technical matters that will solve

In view of this, fundamental purpose of the present invention is to provide a kind of the CIF format circular is cut into the method for PG3600 format rectangle, to solve the too many problem of the tradition overlapping exposed portion of cutting, to reach the purpose that improves pattern generator film speed and exposure quality.

(2) technical scheme

For achieving the above object, the invention provides and a kind of the CIF format circular is cut into the method for PG3600 format rectangle, this method comprises:

Circle is approximate as a positive n limit shape, calculate the value of n, n is a natural number;

Described positive n limit shape is cut into the combination of rectangle and right-angle triangle;

The rectangle that cutting is obtained is merged into a rectangle to greatest extent;

The rectangle of the rectangle external left right half that obtains after merging is merged into rectangular strip in vertical direction, the rectangle of the outside top and the bottom of rectangle that obtain after merging is merged into rectangular strip in the horizontal direction;

The right-angle triangle that obtains for cutting is that one side of rectangle surrounds this right-angle triangle as rectangle with the hypotenuse.

In the such scheme, describedly comprise as a positive n limit shape and the step of calculating the value of n circle is approximate: a string making this circle, make the formed arc height of this string and folded circular arc be less than or equal to the error range 2 μ m of permission, calculate the pairing central angle of this string then, and calculate the ratio k of 2 π and this central angle, then n gets greater than k and is the integer of 4 multiple.

In the such scheme, described described positive n limit shape is cut into the step of the combination of rectangle and right-angle triangle, be by connect on the shape of positive n limit n up and down and symmetrical summit realize.

(3) beneficial effect

From technique scheme as can be seen, the present invention has following beneficial effect:

1, utilize the present invention, mix joining method owing to adopt, so cutting method is very simple, programming realizes easily.

2, utilize the present invention, calculate polygonal limit number according to accuracy requirement, so the figure after the cutting and the error of former figure can be accomplished very little owing to adopt.

3, utilize the present invention, owing to adopt the rectangle folding, so the rectangle data amount that cuts out is very little.

Description of drawings

Fig. 1 is the method flow diagram that the CIF format circular is cut into the PG3600 format rectangle provided by the invention;

Fig. 2 is the synoptic diagram of calculating n value provided by the invention;

Fig. 3 is for cutting into positive n limit shape according to the embodiment of the invention synoptic diagram of the combination of rectangle and right-angle triangle;

Fig. 4 is merged into the synoptic diagram of a rectangle to greatest extent for the rectangle that cutting is obtained according to the embodiment of the invention;

Fig. 5 is for being one side of rectangle surrounds this right-angle triangle as rectangle synoptic diagram with the hypotenuse according to the embodiment of the invention.

Embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.

As shown in Figure 1, Fig. 1 cuts into the method flow diagram of PG3600 format rectangle for provided by the invention with the CIF format circular, and this method may further comprise the steps:

Step 101: circle is approximate as a positive n limit shape, calculate the value of n, n the summit that makes described positive n limit shape on described circle about and left-right symmetric, n is a natural number;

Step 102: the combination that described positive n limit shape is cut into rectangle and right-angle triangle;

Step 103: the rectangle that cutting is obtained is merged into a rectangle to greatest extent, and the horizontal sides length that makes the rectangle after the merging is more than or equal to vertical edges length;

Step 104: the rectangle of the rectangle external left right half that will obtain after will merging is merged into rectangular strip in vertical direction, and the rectangle of the outside top and the bottom of rectangle that obtain after merging is merged into rectangular strip in the horizontal direction;

Step 105: the right-angle triangle that obtains for cutting is that one side of rectangle surrounds this right-angle triangle as rectangle with the hypotenuse.

Comprise as a positive n limit shape and the step of calculating the value of n circle is approximate described in the above-mentioned steps 101: a string making this circle, make the formed arc height of this string and folded circular arc be less than or equal to the error range 2 μ m of permission, calculate the pairing central angle of this string then, and calculate the ratio k of 2 π and this central angle, then n gets greater than k and is the integer of 4 multiple.

The method of calculating n value as shown in Figure 2, Fig. 2 is the synoptic diagram of the n of calculating value provided by the invention.As shown in Figure 2, the geometric relationship among Fig. 2 is as follows:

BC＜2μm

AO＝r，BO＝r-BC

$\cos \mathrm{\α}=\frac{\mathrm{BO}}{\mathrm{AO}}=\frac{r-\mathrm{BC}}{r}$

$\mathrm{\α}=\mathrm{arc}\cos \left(\frac{r-\mathrm{BC}}{r}\right)$

Get $\mathrm{\&alpha;}<\mathrm{arc}\cos \left(\frac{r-2\mathrm{\&mu;m}}{r}\right)$

Order $k=\frac{\mathrm{\&pi;}}{\mathrm{\&alpha;}}$

Described in the above-mentioned steps 102 described positive n limit shape being cut into the step of the combination of rectangle and right-angle triangle, is to realize by about in the of n and the symmetrical summit that connects on the shape of positive n limit.Connect about these, symmetrical point, just positive n limit shape can have been cut into a lot of little rectangles and some right-angle triangles.

The rectangle that described in the step 103 cutting is obtained is merged into a rectangle to greatest extent, and promptly merging those little rectangles is a big rectangle, and the horizontal sides length that makes its rectangle is more than or equal to vertical edges length.

Circle with reality is that example illustrates detailed cutting method of the present invention below.

Step 1, obtain suitable n value, make its about the summit on the circle, the point the most up and down of left-right symmetric and circle also is polygonal summit.Suppose that the n that we calculate is 12.

Step 2, connect about these, symmetrical point, positive n limit shape has been cut into a lot of little rectangles and some right-angle triangles.As shown in Figure 3, Fig. 3 is for cutting into positive n limit shape according to the embodiment of the invention synoptic diagram of the combination of rectangle and right-angle triangle.

Step 3, to merge those little rectangles be a big rectangle, and the horizontal sides that makes its rectangle is more than or equal to vertical edges (as the rectangle ABCD among Fig. 4).Be merged into rectangular strip for the little rectangle vertical direction of the part about beyond the large rectangle and be merged into rectangular strip (as the rectangle EFMN among Fig. 4) for up and down the little rectangular horizontal direction of part beyond the large rectangle.Fig. 4 is merged into the synoptic diagram of a rectangle to greatest extent for the rectangle that cutting is obtained according to the embodiment of the invention.

Step 4, for those right-angle triangles, be that one side of rectangle surrounds this right-angle triangle as rectangle with its hypotenuse.Right-angle triangle ABC as shown in Figure 5, Fig. 5 is for being one side of rectangle surrounds this right-angle triangle as rectangle synoptic diagram with the hypotenuse according to the embodiment of the invention.

Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (3)

1, a kind of the CIF format circular is cut into the method for PG3600 format rectangle, it is characterized in that this method comprises:

Circle is approximate as a positive n limit shape, calculate the value of n, n is a natural number;

Described positive n limit shape is cut into the combination of rectangle and right-angle triangle;

The rectangle that cutting is obtained is merged into a rectangle to greatest extent;

The rectangle of the rectangle external left right half that obtains after merging is merged into rectangular strip in vertical direction, the rectangle of the outside top and the bottom of rectangle that obtain after merging is merged into rectangular strip in the horizontal direction;

The right-angle triangle that obtains for cutting is that one side of rectangle surrounds this right-angle triangle as rectangle with the hypotenuse.

2, according to claim 1 the CIF format circular is cut into the method for PG3600 format rectangle, it is characterized in that, describedly comprise as a positive n limit shape and the step of calculating the value of n circle is approximate:

Make a string of this circle, make the formed arc height of this string and folded circular arc be less than or equal to the error range 2 μ m of permission, calculate the pairing central angle of this string then, and calculate the ratio k of 2 π and this central angle, then n gets greater than k and is the integer of 4 multiple.

3, the method that the CIF format circular is cut into the PG3600 format rectangle according to claim 1, it is characterized in that, described described positive n limit shape is cut into the step of the combination of rectangle and right-angle triangle, be by connect on the shape of positive n limit n up and down and symmetrical summit realize.

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