TW522468B - Method of determining exposure reference point on wafer - Google Patents

Abstract

This invention discloses a method of determining an exposure reference point on a wafer, suitable for positioning a wafer in an exposure apparatus to configure the most total number of dies. Firstly, an initial point is determined on the outer side of the wafer. Then, from the initial point, the wafer is divided in units according to the exposure area, in which the initial point is one of the apexes of an unit area and the unit area can be fully divided by one or a plural number of die units. The total number of the die units at the valid position of the wafer is calculated to be the information of the total number of die related to the initial point. Finally, the initial point is regarded as the origin of the coordinates with the aid of five times of decile approximation to acquire the initial point for the most total number of die units, which is used as the exposure reference point.

Description

522468 5. Description of the invention (1) Field of the invention: The present invention relates to a semiconductor process technology, in particular to a method for determining the exposure reference point of a wafer, for arranging the maximum number of wafers on the wafer. Relevant technical description: As semiconductor integrated circuit technology improves, the integration of components also increases, thereby increasing the value of the die. Therefore, how to make the largest number of wafers in a wafer to obtain greater profits has become an important subject in process technology research and development. However, the exposure equipment currently used to plan the wafer configuration of wafers, such as the exposure equipment of Dutch manufacturer ASML, usually provides calculation aids that cannot accurately calculate the initial exposure position and cause waste of wafer space. Not only can it not effectively reduce costs, It also reduced profits. On the other hand, the computational aids provided are time consuming and inefficient. In order to further explain the above-mentioned problems, the following describes the conventional method for determining the reference point of wafer exposure with reference to Figures 1a to b. Please refer to Figure 1a, which shows a schematic diagram of conventionally setting a wafer exposure reference point. First, the center 0 of an 8-leaf wafer 100 is used as the coordinate origin, and a starting point (Xπ, π) is determined outside the wafer 1000. Next, starting from the starting point (X ", Y "), the wafer 100 is divided into unit areas with the exposure area 1 〇2 set as the exposure δ and prepared (not shown), so that these unit areas 1 0 2 completely covers the surface of the wafer 100, where the starting point is one of the vertices of the cell region 102 and the cell region 102 can be completely divided by the 6 wafer cells 102a. (Not shown) calculations are located on the wafer

0503-6795TWf; TSMC2001-0707; Spin.ptd Page 4 W2468 V. Description of the invention (2) Numerically, it is the effective position 100a of the early 70 area 102. The total unit of the wafer unit 102a :: 1 The starting point (x'r)-the total number of wafers. Among them, there is no mark M wafer alignment mark AM. Refer to Figure 15 ', which shows the unit area 50a, etc. of the first la_. The horizontal and vertical axes of the unit area 102 are divided into 24 and 25 "51 fixed points. Finally, each-fixed point is taken as the calculation and the total number of wafers corresponding to these fixed points is 02: bucket is: The fixed point is used as the reference for exposure, "Zhong 'is based on the fact that you have m ^ ^ ^ ^ ^ and you use this reference point as the basis for exposing nine positions to prepare the position crystal. However, this type of crystal is only for her Dou Zhifei is 〇 10 nose out 1 Z 7 Chapter 5 said the number of pieces of w. It can be said that the time-consuming and ineffective accuracy is only 〇 丨, and the helmet is half the ancient sheep and the reference point displacement of the wafer, Stopping the door and combining ..., the method effectively allocates up to W days of wafers on the wafer, resulting in a waste of wafer space. In view of this, the present invention describes a method, a method that you can use The number of exposure reference points of the wafer is very high. By using the accurate approximation method of the exposure reference points determined by the +5 and 5 sides in total, the accuracy of the pre-production date on the wafer is improved to 0. · 0 0 0 1 ， and the calculated period of f is also greatly reduced. It can be said that the production of Purple Miaotai is increased by the maximum amount on the Sunday®. The wafer further captures the competition in the housing industry and increases profits. Summary of the invention: The purpose of the present invention is to describe the method, i_ can determine the exposure reference point of the wafer from eighteen, s, and n. Wafers, a & good exposure first reference points after the number. Wrong to arrange the most wafers on the wafer. According to the above purpose, this article provides a kind of exposure parameters for the wafers.

522468 V. Description of the invention (3) Test method, white Xr ,. mark the origin, outside the circle / ^: U) Use the center of a wafer as a seat. (X, Y); (b) Divide from the starting point i to == ϊ to divide the first rectangular area as a unit, so that these products 70 are all covered on the wafer surface, where the starting point is the first A rectangle: = "The vertex and the first rectangular area can be completely occupied by one or more wafer units ^ = two, the difference is located in the effective position of these first rectangular areas on the wafer. , With the total number of wafers as one of the corresponding starting points; one with the starting point ^ as the coordinate origin, extending a first and a predetermined distance to the horizontal and vertical axes respectively to form a target block, where the first And 箆 equal parts to determine (n + 1) 2 fixed points; 21 the total number of wafers of these fixed points; 直 from these fixed points to the point directly: composition-the second rectangular area, where the second rectangular area … The total number of wafers corresponding to the total of all wafers is 4 before the total number of wafers; (g) the second rectangular area is used as the new seat. And the vertical axis are divided into η equal parts to re-determine (η ^, (h) repeat steps (e) to ⑷ a total of 0y times, and m times: 2) to (f); and (i) select Select the complex set point with the maximum total number of wafer units as the exposure reference point. Furthermore, () ·) is used to get older; ^ ,, ^, which contains the Wth of the wafer ^, said 0 The step of the relative position between the centers. Among them, the step (/, point (X, Y) depends on the following relationship ... X (mm) =-(the beginning of the wafer half (the horizontal distance of the first rectangular area)) x 2/3 i; Y (mm) two (say ^ one diameter)-(marking retention distance)-u. In addition, the first and second: fixed distance

522468 V. Description of the invention (4) are about 20 cm, and the values of η and m are 10 and 4, respectively. Brief description of the drawings: In order to make the above-mentioned objects, features, and advantages of the present invention more comprehensible, the following describes the preferred embodiments in conjunction with the attached drawings to make detailed descriptions as follows: Section 1a A schematic diagram of conventionally setting a wafer exposure reference point is shown. Figure lb is an enlarged view of the cell area in Figure la. FIG. 2 is a schematic diagram showing a wafer exposure reference point according to an embodiment of the present invention. Fig. 3 is a schematic diagram showing the coordinate block in Fig. 2 with (X, Y) as the origin. Fig. 4 is a schematic diagram showing a preferred exposure reference point for a wafer according to an embodiment of the present invention. FIG. 5 is an enlarged view showing a slanted area in FIG. 4. [Explanation of symbols] 100, 2000 ~ wafer; 102 ~ exposed area; 102a, 202a ~ wafer unit; 204 ~ coordinate block; 100a, 200a ~ effective position; 202 ~ first rectangular area; 2 0 6 ~ the second rectangular area; horizontal distance between a ~ 0 and 0 ;; vertical distance between b ~ 0 and 0;

0503-6795TW; TSMC2001-0707; Spin.ptd Page 7 522468 V. Description of the invention (5) AM ~ wafer alignment mark; N ~ notch; 0 ~ wafer center; 0 '~ The center of a rectangular area. The detailed description of the preferred embodiment: The method for determining the wafer exposure reference point according to the embodiment of the present invention is described below with reference to FIGS. 2 to 5 and is applicable to positioning a wafer in an exposure apparatus. Referring to FIG. 2 in May, it is impossible to draw a schematic diagram of determining a reference point for exposure of a wafer according to an embodiment of the present invention. First, a computer (not shown) simulates a physical wafer map (hereinafter referred to as a wafer), and performs the first step (a), using the center of the wafer 2000 as the origin of coordinates (Marked 0 in the figure), a starting point (X, γ) is determined on the outside of the wafer 200, where the starting point (X, Y) depends on the following relationship: X (mm) =-(crystalline Circle radius) one (horizontal distance of the exposure area 2/3 one 1 Y (mm) = (wafer radius) one (remaining distance of the score N) ~ 1. 4 In this embodiment, the used wafer 2 The size of 0 0 is 8 leaves, so the wafer 200 radius is about 100 cm (mm), and the exposure area 202 (hereinafter referred to as the first rectangular area) of the exposure equipment (not shown) is about 24 X 16 mm 2 (- Approximately 20x 20 mm2 'depending on customer needs). In addition, the notch reserve distance (notch reserve distance) of 8-leaf wafer 2000 is 8 to 9 mm ° Then proceed to step (b)' From here Starting from the point (X, Y), the wafer 200 is taken as the unit of the exposure area (first rectangular area) 202 set by the exposure equipment.

0503-6795TWf; TSMC2001-0707; Spin.ptd page 8 522468 V. Description of the invention (6) --- == is such that the first rectangular area 2 0 2 completely covers the surface of the wafer 2 0, 8 The middle starting point (X, Y) is one of the vertices of this first rectangular region 20 2, such as 2 f = no, and the first rectangular region 202 can be completely covered by one or more wafers (die early 2 0 2 a Divided. In this embodiment, the first rectangular area 002 can be completely divided by the 6 wafer units 202a. However, the present invention is not limited to this depending on the size of the wafer 200 and customer requirements. Next, step (c) is performed, and the total number of wafer units in the effective position 2000a of these first rectangular areas 202 on the wafer 2000 is calculated by a computer as a corresponding number of the starting point (X, γ). Data of a total number of wafers. The valid position 2000a here refers to the portion of the first rectangular area 200 that is completely located within the wafer 200, j and the first rectangular area 2 that intersects the edge of the wafer 200. 〇2, however, the area of the parent set after the intersection does not include two wafer alignment marks M (aiignment mark) and can be used by one or more wafer units 2〇 The part divided by 2a. Next, step (d) is performed. Please refer to FIG. 3, and use the starting point (χ, γ) as the coordinate origin to extend the first and second predetermined directions to the horizontal and vertical axes, respectively. The distance 'is, for example, about 16 and 24 mm or both about 20 mm to form a target block 204. In this embodiment, the size and shape of the coordinate block 204 are the same as those of the first rectangular region 202. Among them, The first and second predetermined distances are each divided into 10 equal parts to determine (1 0 + 1) 2 fixed points. Next, step (e) is performed, and each fixed point is used as a starting point, and the steps are repeated ( b) to (c) until the total number of wafers corresponding to the 12 fixed points is obtained. Next, step (f) is performed, and referring to FIG. 3, from the fixed points, 4 fixed points adjacent to each other are selected to form a The second rectangular area 206, in which the total number of wafers corresponding to the four fixed points in the second rectangular area 206 is all

522468

5. In the invention description (7), the total number of wafers has 4 records before the total number of wafers. The next step (g) is to use the second rectangular area 206 as a new coordinate area (not shown), and use the above method to divide the horizontal axis and the vertical axis into 10 equal parts each to re-determine (1 0 + 1) 2 fixed points. Then proceed to step (h) 'Repeat steps (e) to (2) a total of 3 times, and repeat step (e) to the next & step and then proceed to step (i), obtained from the last approximation From the total data of 4 wafers, the fixed point with the largest total number of wafer units 202a is selected as the exposure reference point. Zheng

^ Please refer to FIG. 4, which illustrates a schematic diagram of a preferred exposure reference point according to an embodiment of the present invention. In the above steps (1) to (10), the original starting point (X, Y) is approximated by 4 times using the decisive approximation method to obtain the starting point (χ ,, γ, ), Which is the preferred exposure reference point of the present invention. Similarly, starting from this reference point (χ ,, γ,), the first rectangular area 202 is used as a unit to divide the wafer 200, and the result is as shown in the fourth As shown in the figure, in this way, the accuracy of the exposure reference point (X, Υ ') obtained can reach 0.000, which is 3 orders of magnitude higher than the exposure reference point of the conventional technology. On the other hand, After 1 + 4 calculations, 1 2 J points each time. About 6,000 wafers are recorded in ten noses. However, compared to the conventional technology (1 time, a total of 1 2 7 5 points), about 1 For the total number of 300 wafers, the operating time can be greatly reduced by 2 times. Next, please refer to Figures 4 and 5, where Figure 5 is an enlarged view of the oblique line area in Figure 4. Step (j) is performed, and the reference point (X ,, Y,) is used as the coordinate origin to calculate a first rectangular area containing the wafer center 0

The center of the 522468 and the center of the wafer are in a circle. The center of the circle is located in the first rectangular area. 5. Description of the invention (8) (that is, the oblique line area in FIG. 4) The positional relationship. As shown in FIG. 5, the distance from the left side of the 'heart 0' is 3 and the distance from the top is b. Finally, step (k) is performed, and the physical wafer is placed in the exposure equipment based on the relative position relationship. Among them, the relative position between the center of the wafer and the center of the exposure area of the exposure equipment is arranged according to the above relationship. ^ According to the method of the embodiment of the present invention, the placement position of the wafer can be accurately determined in the exposure equipment. According to this position, the maximum number of chips can be arranged on the wafer. That is, the competitiveness and profitability of the industry can be increased by upgrading the wafers of a single wafer. Although the present invention has been disclosed in the preferred embodiment as described above, Iron 1 limits the present invention. Anyone skilled in this art can not change: the two are not used within the scope of God and can be modified and retouched. Therefore, the present invention It is clear that Jing Dang shall be subject to the definition of the scope of patent application attached. "Protection range

Claims (1)

522468 ———————— 6. Scope of Patent Application Steps · A method for exposing the exposure reference point of a wafer includes the following steps: (:) 2: crystal. The center is used as the origin of the coordinates, and the point 'Dingyuanyi' is started from the outside of the wafer. The wafer is taken as a single rectangular area, so that the first rectangular areas are completely filled with the On the wafer surface, ^^ f is a vertex of the first rectangular area, and the first rectangular area can be divided by a plurality of wafer units; the first rectangle is located on the delta wafer. In the effective position of the zone, the total number of the day and the day is used as the total number of wafers corresponding to one of the starting points. (D) The starting point is used as the coordinate origin, and the horizontal axis and the vertical axis are respectively extended to the first and second axes. Two predetermined distances to form a target block, in which the first and second predetermined distances are divided into n equal parts, so as to determine (η + ι) 2 fixed (7) starting with each such fixed point Point, repeat steps (b) to (C) to obtain ^ corresponding to the total number of chips of the fixed points; one (f) choose four fixed points next to each other to form two, two Rectangular area, in which the fixed points correspond in the second rectangular area: The total amount of materials in the total sum of all the wafers has the most 4 before the number of wafers; the median (f I takes the first rectangular area as a new coordinate block, and divides the horizontal axis and the sword into n equal parts to re-determine (η + 1) 2 Fixed point; (h) Repeat steps (e) to (g) for a total of m — [times, and repeat the steps for the claw times — 〇 05〇3-6795Bif; TSMC2001-0707; Spin.i page 12 522468 6. Apply for a patent Range (e) to (ί); and (i) select the fixed point with the maximum total number of wafer units as the exposure reference point. 2. Set the exposure reference point of the wafer as described in item 1 of the scope of patent application Method, which further includes a step (j): using the reference point as a coordinate origin, calculating a relative position between the center of the first rectangular region containing the center of the wafer and the center of the wafer. The method for determining the exposure reference point of a wafer as described in item 1 of the patent scope, wherein the starting point (X, Y) of step (a) depends on the following relationship: X (mni) =-(crystalline Circle radius)-(horizontal distance of the first rectangular area) x 2/3-1 Y (mm) = (wafer radius)-(notch retention distance)-1.4. 4. The method for determining the exposure reference point of a wafer as described in item 3 of the scope of patent application, wherein the size and shape of the first rectangular area are the same as the exposure area of a wafer exposure equipment. The method for determining the exposure reference point of a wafer as described in item 1, wherein the coordinate block size and shape of step (d) are the same as the first rectangular area. 6. The determination as described in item 1 of the scope of patent application A method for obtaining a reference point for exposing a wafer, wherein the first and second predetermined distances are approximately 20 cm. 7. The method for determining a reference point for exposing a wafer as described in item 1 of the scope of patent application, wherein The value of n is 10. 8. Determine the exposure reference of the wafer as described in item 1 of the scope of patent application 0503-6795TWf; TSMC2001-0707; Spm.ptd page 13 522468 6. Method of applying for a patent point, where the m value is 3. 9. · A method for determining the exposure reference point of a wafer, which is suitable for — preparing a wafer with a middle position, including the following steps: 〃 (a) Use the center of the wafer as the origin of the coordinates, and set the outside of the wafer. A starting point (X, Y) is determined, where the starting point (X, Y) depends on the following relationship: X (mm) (wafer radius)-(horizontal distance of the exposure area) χ 2/3 Y (mm) = (wafer radius)-(remaining distance of nicks)-1 · 4; (b) starting from the starting point, dividing the wafer with the exposure area set by the exposure equipment as a unit area so that the unit areas are complete and the wafer surface is full, where the starting point is the Unit area—the vertex and the read exposure area can be completely divided by one or more wafer units; (c) Calculate the total number of the wafer units in the effective positions of the unit areas on the wafer as the starting point corresponding to them One chip total data; (d) using the starting point as the coordinate origin, extending a first and second predetermined distance to the horizontal axis and vertical axis respectively to form a target block, where the first and second A predetermined distance is divided into η equal parts, so as to determine (η + 1) 2 fixed points; (e) Using each of these fixed points as a starting point, repeat steps (b) to (c) until the total number of wafers corresponding to those fixed points is obtained; (f) Select four of these fixed points that are related to each other. The fixed points next to each other constitute a rectangular area, in which the total number of wafers corresponding to the fixed points in the rectangular area is before all the total number of wafers has the maximum total number of wafers. 522468 6. Apply for 4 patents; (g) Use this rectangular area as a new coordinate block, and divide the horizontal axis and vertical axis into η equal parts to re-define (η + 1) 2 fixed points; ( h) Repeat steps (e) to (g) for m — 1 time, and repeat steps (e) to (f) for the mth time; and (i) select the fixed point with the maximum total number of wafer units as the exposure reference Point; (j) using the reference point as the coordinate origin, calculate the relative position relationship between the center of the exposure area containing the center of the wafer and the center of the wafer; and (k) use the relative position relationship as a positioning According to this, the wafer is placed in the exposure equipment. 10. The method for determining the exposure reference point of a wafer as described in item 9 of the scope of the patent application, wherein the coordinate block size and shape of step (d) are the same as the exposure area. 11. The method for determining an exposure reference point of a wafer as described in item 9 of the scope of the patent application, wherein the first and second predetermined distances are about 20 cm, respectively. m 1 2. The method for determining the exposure reference point of a wafer as described in item 9 of the scope of the patent application, wherein the value of n is 10. 1 3. The method for determining the exposure reference point of a wafer as described in item 9 of the scope of patent application, wherein the m value is 4. 0503-6795TWf; TSMC2001-0707; Spin.ptd page 15