JPS5844714A - Changer for figure - Google Patents

Abstract

PURPOSE:To draw the digure with angles at high speed with high accuracy by smoothly changing the length of rectangular beams by utilizing the scanning signals of electron beams. CONSTITUTION:Data to be drawn 22 are set to buffer registers 23, the coordinates of the figure are arithmetically operated by means of the Y coordinate arithmetic circuit 24 and X coordinate arithmetic circuit 29 of a coordinate arithmetic circuit 37, and value required is obtained. The results of the arithmetical operation are transmitted to a figure discriminating circuit 25, and the parameters of characteristics displaying the characteristics of the figure are calculated by means of the circuit 25 and transmitted to a ROM26. The ROM26 uses the parameters as address value, and value previously written is outputted, and forwarded to an output control circuit 27. Output gate control signals 34 outputted from the circuit 27 are given to an output gate 28, data needed are selectively controlled from Y coordinate output 32 and X coordinate output 33 by the signals 34 in the gate 28, and output 35 for drawing is successively outputted, and written to a drawing memory.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a graphic converter for an electron beam lithography system, and more particularly to a graphic converter for high-speed lithography using all rectangular beams.

Conventional electron beam lithography systems include a spot beam system and a rectangular beam system, but the former has the disadvantage of low throughput, and the latter takes time to draw diagonal figures. Increasing the accuracy of graphics has the disadvantage that it consumes more and more time, and the graphics data required to draw using these drawing methods - when it comes to T'SI and VLSI, the number of graphics becomes enormous, and it is difficult to use electronic computers. In this method, it takes a long time to convert data, which prevents throughput from decreasing.

An object of the present invention is to provide a high-speed drawing figure for an electron beam lithography system that can draw angled figures at high speed and with high precision by smoothly changing the length of a rectangular beam using an electron beam scanning signal. Provides a graphical converter to convert.

Graphical data of a semiconductor device is generally provided to a drawing apparatus in the format shown in FIG.

That is, (X, Y) is the center coordinate of the figure, W is the width of the figure, I is the height of the figure, and θ is the inclination of the figure.

Since it is difficult for electron beam lithography equipment to write with data as it is, it is necessary to use 5R41 in the most suitable data format for the equipment.
! IL, draw 1 mountain.

FIG. 2 shows a form of figure conversion in which the beam length of a rectangular beam is made variable to achieve high-speed drawing. In Figure 2, the left rectangle is left as is, and the right angle rectangle is divided as shown in the □ figure. For actual drawing, it is further divided as shown in FIG.

The divided figures can be expressed as five types of basic figures as shown in FIG. The data format of this basic figure is the electron beam 0N in the electron beam scanning direction of the coordinate plane.
10FF coordinate data BON, BOFF% angle data AΦ.

It is expressed as Aθ, B, Be, and electron beam length data Bt.

Conventionally, these data conversions were performed using electronic computers, but as the number of graphics becomes enormous with LSI and VLSI, it takes a long time to convert using methods using electronic computers due to the large number of graphics. Furthermore, when drawing this converted data, it takes a long time to transfer the data from the electronic computer or external storage device to the drawing control device, making it difficult to shorten the overall drawing time.

The figure converter of the present invention is used to overcome this drawback.The figure converter is used to cover this drawback. Figure 4 shows a dedicated graphic converter that converts at high speed.

The data conversion method will be explained using the diagram in FIG.

In FIG. 7, the graphic data provided by the magnetic tape device 1 as the graphic data in FIG. 1 is divided by the computer 2 as shown in FIG. 2 and stored on the magnetic disk 3. computer 2
The drawing sequence program is activated by the operator's instructions, and the drawing data is transferred from the magnetic disk 3 in the drawing order through the computer 2 to the drawing data memory 4, and sequentially sent to the figure converter 5, as shown in FIGS. 3 and 4. Converted 扛 as shown in the figure,
It is stored in the drawing memory 6 and sent to the drawing signal generator 7 for each drawing unit, where it is converted into a signal suitable for the electron optical system 8 and the electrons 1i! 'kON-OFF or deflect to draw a figure on the sample 21. As is well known, the electron optical system 8 includes an electron gun 11, an irradiation lens 12, a blanking plate 13, a blanking aperture 14, a shaping deflection plate 15, a rectangular aperture 16, a reduction lens 17, an X-axis side plate 18, and a Y-direction plate 18. It consists of an axial plate 19 and an objective lens 20. The conversion speed of the figure converter 5 at this time is 100% in accordance with the drawing speed of the electron optical system 8.
A high speed of n seconds to 1 microsecond at the latest is required.

In the present invention, as shown in FIG. 8, when the drawing data 22 is set in the buffer register 23, the X coordinate calculation circuit 29
, the coordinates of the figure are calculated by the X coordinate calculation circuit 24, the calculation results are sent to the figure identification circuit 25, where the figure is identified from each coordinate value, and the value ? Speeding up is realized by outputting the necessary value from the output gate 28 based on the value in the ROM 26.

FIG. 8 is a block diagram showing one embodiment of the present invention.
The figure shows an example of output from the figure detection circuit and ROM.

The drawing data from the drawing data memory 4 shown in FIG. 7 is set in the buffer register 23 from the drawing data 22 shown in FIG. The figure shown in FIG. 5 will be explained in order by taking as an example. The data is set in the buffer register 23 corresponding to Xo * Yo, and arithmetic calculation is performed by the Y coordinate of the coordinate calculation circuit 37, the calculation circuit 24, and the X coordinate calculation circuit 29 under the control of the 1-data conversion control circuit 36. %XOeY
Os x2 *y1 @A@Bg x6, xl
(7) The value is determined. Here ~ yo I y,
# y, I Trapezoid x, which is a squared figure in Y8.

becomes x0=X, , -Δx, x1=xat (X,
is the X electromagnetic deflection value 30, ΔX is the drawing width 31), '10
e YO * y2 * Ys are each calculated by the following formula.

Yo = Yo + ((X-Xo)-ΔX)jan
A'/l = Yt + ((X-X.)-ΔX)tan
13Yv = Yo + (>L-XO) jan A
y3=y, + (x, -Xo)tanB In the right case of drawing this trapezoid, the trapezoid is further divided into two upper and lower triangles and a square in the center, a total of three parts, as shown in FIG. BON,
BOFFI Beam length BL% angle variation information Aes Ae
e Bg, Aevi - It is necessary to output these values, but these values are a quadrilateral, a triangle, and a trapezoid, based on the drawing data 22 that all the initial coordinates were calculated.

Unlike parallelograms, each shape is a BON.

The BOFF, angle information, and number of divisions in the Y direction are different. This Rk
It is extremely difficult to perform calculations for each figure. In the present invention, the feature parameter representing the feature of the figure is calculated by the figure identification circuit 25 from each calculated coordinate value, and the parameter?
The address value of the ROM 26 is the value previously written in the RAM 26 based on the parameter value from the figure identification circuit. By selectively controlling the output gate 28 using the output gate control signal 34, the drawing output 35 is sequentially written into the drawing memory 6 in FIG. 7. An example is yo, y, e Y2 in Figure 5.
If we take the shape of s Y3, this trapezoid is No. 9 in Figure 6.
This corresponds to
0'', and the output from the ROM 26 is divided into three pieces in the Y direction, and the first figure is BON value = Y2, BOF
F='Jo-Angle=θA, to the second figure, B”ON=
'! 0, Boyr=y8. Angle 20, the third figure is BoN=ytsBOFF=)'3, angle=O
The value of B is output. In this way, it became possible to convert all shapes into one shape with a simple circuit, and my father,
The opening time during conversion is 100 to 2000 seconds for shapes without angles,
In the case of an angled figure, the figure can be converted as quickly as 1 μsec or less, although it depends on the multiplication calculation time, which has the effect of improving the drawing speed of the entire electron beam drawing apparatus.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of general figure data, Fig. 2 is an explanatory diagram of a figure division method, Fig. 3 is an explanatory diagram of a figure division method necessary for drawing, and Fig. 4 is an explanatory diagram of a figure division method necessary for drawing. is an explanatory diagram of the basic figure after figure division, FIG. 5 is an explanatory diagram of the Y coordinate calculation method, FIG. 6 is an example diagram of figure detection-1 path and ROM output, The figure is a block diagram of an electron beam lithography control device, and FIG. 8 is a block diagram of a figure f converter according to an embodiment of the present invention. 24...X coordinate calculation circuit, 25. ...Graphic identification circuit 1
．． '28...Output gate, 29...X coordinate calculation circuit. 1st mouth 20th 3rd figure 4-mouth ¥ys diagram X% 6th day plan 7121

Claims (1)

[Claims] 1. In a figure converter of a charged particle lithography apparatus such as an electron beam lithography apparatus that controls charged particles such as electron beams or ions to draw patterns such as semiconductor integrated circuits on a wafer or mask, a coordinate calculation circuit for divided figures. A figure converter comprising: a figure identification circuit that identifies figures based on the calculated value from the coordinate calculation circuit; and an output gate circuit that selects and outputs necessary data based on the output from the figure identification circuit. .