JPH03188649A - Lsi wiring modifying method - Google Patents

Abstract

PURPOSE:To decrease probability of short circuit between adjacent wirings and improve reliability, by a method wherein a shiftable wiring is automatically shifted by using routing data prepared on the basis of a routing algorithm. CONSTITUTION:Element layout of an LSI and its routing data are stored in a disk equipment 24; a specified amount of the routing data are read from the equipment 24 to a main memory 22; adjacent route is searched about the routing data. When one of the adjacent routes is not used all over the whole length of said wiring, a segment start pointer is modified to deal with the wiring grid on the side not used, and the route is shifted. Said shift requires the condition that wirings do not exist at the adjacent wiring grid position in the moving direction when the route is shifted.

Description

[Detailed Description of the Invention] [Summary] Regarding an LSI wiring change method that moves a wiring by determining whether or not there are wires that have been routed on both sides of the wiring to be moved, the wiring is performed using wiring data created according to a wiring algorithm. The purpose is to automatically move movable wiring among already completed wiring, and it is a wiring that connects each element formed on a semiconductor substrate and exists on the same wiring layout grid position. In a CAD system in which wiring position display data corresponding to each wiring is stored in a readable manner using an access pointer assigned to each wiring position, the wiring position display data is read out using the corresponding access pointer, and the wiring position display data is read out using the corresponding access pointer, and the wiring position display data is read out using the corresponding access pointer. The data of the wiring sections in the wiring position display data corresponding to the wirings are compared, and the wiring corresponding to the compared wiring position display data is moved by the unit wiring arrangement grid interval on the semiconductor substrate, and the wirings are adjacent to each other. If they are adjacent to each other at an interval of one unit wiring arrangement grid interval or more, the access pointer of the wiring position display data of the wiring to be moved is changed to the access pointer of the one adjacent wiring arrangement grid in the movement direction. I configured it as follows.

[Industrial Field of Application] The present invention relates to an LSI wiring change method that moves a wiring by determining whether or not there are already wires on both sides of the wiring to be moved.

Although LSIs have come to be used in various electronic products, the yield of LSIs is currently not very good, and the reason for this is said to be short circuits between wirings forming LSIs. Wiring forming an LSI is placed at predetermined wiring layout grid positions on a semiconductor substrate, and the positions are determined according to a conventional wiring algorithm. There are various wiring algorithms, but the wiring layout grid positions determined by these algorithms are completely different from determining whether or not a short circuit will occur between wiring as described above. The decision is made based on whether or not the wiring and wiring can be integrated compactly in the required area on the limited semiconductor substrate.

(Prior Art) As mentioned above, each wiring forming an LSI is wired according to a preselected wiring algorithm, and the area used for the wiring is approximately 70% of the semiconductor substrate, with the remaining 30% being used for wiring. % is the cell area.Also, the area occupied by the wiring within the overhead space used for wiring varies depending on the wiring algorithm used, but it remains at most 50%.In other words, no wiring is placed. Approximately 50% of the area on the semiconductor substrate surface where wiring is actually formed remains.

(Problems to be Solved by the Invention) The current situation is that elements and wiring on a semiconductor substrate are integrated as described above, but the yield of LSI in such an integrated state is low as described above. The main cause of this is short circuits between wiring lines, as mentioned above.

Short circuits between wires, of course, result from the extremely narrowly spaced wire placement grid positions used in integration, but the aforementioned wires are closely spaced in relation to the elements, i.e., at every wire placement grid spacing. There are places where the wiring runs, and there are places where the wiring is arranged sparsely, that is, the wiring runs at several wiring grid intervals.

Even if the wiring is determined according to the wiring algorithm described above, even in places where there is space between the wirings as just mentioned, the number of wirings placed on the semiconductor substrate is tens to millions. In this case, the number is relatively large. It is conceivable that this fact can be effectively utilized to improve the yield of LSI.

However, it is not possible to use wiring data determined according to the wiring algorithm described above to determine where among the hundreds of thousands to millions of wires the usage point is located as described above. This is not only an extremely complicated task, but also requires a large amount of labor.

The present invention was created in view of such problems, and is an LSI wiring modification method that can automatically move movable wiring among already routed wiring using wiring data created according to a wiring algorithm. Its purpose is to provide a method.

[Means to solve the problem]

The present invention provides wiring position display data for each wiring that connects each element formed on a semiconductor substrate and exists on the same wiring layout grid position using an access pointer assigned to each wiring position. CA to be stored readably
In the D system, the wiring position display data is read out using a corresponding access point ladder, data of wiring sections in the wiring position display data corresponding to the wirings on both sides on the semiconductor substrate are compared, and the compared wirings are If the wiring corresponding to the position display data is moved by the unit wiring arrangement grid spacing on the semiconductor substrate and the adjacent wirings are still adjacent to each other at an interval of one unit wiring arrangement grid spacing or more, then the wire to be moved is The access pointer of the wiring position display data is changed to the access pointer of the wiring layout grid that is one adjacent in the moving direction.

[For production]

Using wiring position display data that is generated on a conventional CAD system and read out using an access pointer in the wiring data stored in a disk device, etc., the wires displayed by the wiring position display data are adjacent to each other on both sides. Compare the wiring section data in the wiring position display data.

When the wiring to be compared is moved by one unit wiring layout grid spacing on the semiconductor substrate, and a gap of one unit wiring layout grid spacing or more still remains between the wiring and the wiring on both sides. changes the access pointer corresponding to the wire to be moved to the access pointer of one unit wire placement grid in the moving direction.

By moving the arrangement position, it is possible to reduce the probability of short circuit between wirings. It will improve the yield of LSI,
It also improves reliability.

〔Example〕

FIG. 1 shows an electronic computer system implementing the present invention.

In this figure, 20 is a central processing unit (CPU) 22
24 is a main memory, 24 is a disk device, and 26 is a display device. These devices 20.22.24.26 are interconnected via a bus 28. Display device 2
6 is provided with a keyboard 30. The disk device 24 stores data indicating the element layout of a large-scale integrated circuit (LSI) designed by the above-mentioned known CAD, which is built in the computer system, and the wiring connecting these elements. In addition to storing therein, a program for generating the data and a program for executing the processing flow of the present invention shown in FIG. 2 are also stored.

Among these data, data indicating wiring, which is necessary in connection with the present invention, is hereinafter referred to as wiring data. The wiring data has a list structure as shown in FIG. 3, and describes physical wiring positions on the semiconductor substrate. Reference number 50 refers to the segment list. However, FIG. 3 shows an example expressed in a specific relationship with FIG. 4.

An example of the physical wiring situation on the semiconductor substrate is schematically shown in reference numeral 54 in FIG. Figure 4 (Figure 3)
Reference numerals 52 shown on the left side of FIG. 2 indicate each segment start pointer used in a program that executes the processing flow of the present invention shown in FIG. 2 described above. There is one segment start pointer for each horizontal line of the wiring layout grid formed on the semiconductor substrate, and each segment start pointer points to the first segment in the segment list.

The segment start pointer is the start address of each segment in the segment list structure shown in FIG. 3 above. Each segment consists of a starting point coordinate value, an ending point coordinate value, a pointer, and other attribute data of the wiring described by the segment. The segment is
For each wire existing within a horizontal line of the wire placement grid represented by the segment start pointer, each of those segments is chained by said pointer. However, the chain end data is placed in the pointer of the last segment in the horizontal line, and if there is only one segment, no-chain data is placed.

The processing of the present invention under the system configuration as described above will be explained below.

Prior to starting the process of the present invention, as described above, data indicating the element layout of the LSI and its wiring is stored in the disk device 24, which has been generated using the conventionally known CAD technique. shall be. It is assumed that examples of the wiring and the wiring data are as shown in FIG. 4 and FIG. 3, respectively. It is assumed that a program for executing the processing flow shown in FIG. 2 is also stored in the disk device 24.

When the process shown in FIG. 2 regarding the wiring data stored in the disk device 24 is started, the disk device 2
A predetermined amount of wiring data from 4 is read into the main memory 22, and adjacent wiring is searched for the wiring data (see Sl in FIG. 2).

This search is performed using the segment start pointer described above, and is applied to each wiring accessed by the segment start pointer.

For each of the adjacent wires, it is determined whether or not both sides of the wire are vacant (see 32 in FIG. 2). If both sides of the wiring are not empty (No. 82 in Figure 2)
) and searches for the next adjacent wiring (see S in Figure 2).
(Refer to 1), if one side of the adjacent wiring is empty over the entire length of the wiring, change the segment start pointer corresponding to the wiring to correspond to the wiring layout grid of the empty side and start that wiring. move. This movement is conditioned on the condition that no wiring exists in the adjacent wiring placement grid position in the direction of movement in the state of movement to one side. To explain this using FIGS. 5 and 6, the segment start pointers for the wires ■, ■, and ■ that were set as the segment start pointers corresponding to the third wiring layout grid before this movement are as follows: This is used as the segment start pointer for the second wiring layout grid (see 52 in FIGS. 5 and 6). This movement is
This is allowed because there is no wiring in the wiring section at the wiring position of the first wiring layout grid. The position in the segment list of each segment chained from this segment start pointer remains the same.

If one side of the adjacent wiring is vacant over a part of the wiring, the wiring part to be moved (the sixth
(See the dotted line in the figure) A new segment is generated. The new segments are ■ and 0 in FIG. A segment [phase] is generated by setting its segment start pointer to be the same as the segment start pointer of segment (2), setting the starting point coordinate value of the segment to 216, for example, and leaving the ending point coordinate value unchanged.

The generated segment [phase] is placed next to the last segment @ in the wiring data (see Figure 5), but this segment [phase] is placed within the 8 p segment ■ so that it is chained from segment ■. The pointer is modified to point to the location where segment ■ is placed. Furthermore, the generation of segment (■) is performed by setting the segment start pointer to the segment start pointer corresponding to the 9th wiring layout grid, and setting the start point coordinate value and end point coordinate value within the segment to, for example, 151 and 216 ( (See Figure 6). Segment @ is placed next to segment ■ (see 50 in FIG. 5). The movement of segment (2) is allowed because there is no wiring in the wiring section at the wiring position of the 10th wiring layout grid.

Similarly, segment ■ moves its entire wiring,
In addition, for the segment @, the entire wiring or a part of the wiring is moved. The partial movement of the wiring represented by the segment @ is similar to the partial movement of the wiring represented by the segment ■, and the movement is represented by a dashed-dotted line, and the movement is represented by the segment ■.

When the above-mentioned movement process is completed (54 in FIG.
), and file the wiring data after movement (see 85 in FIG. 2). Segment [phase] is placed next to segment ■ in the segment list.

In this case, the pointer of the segment ■ is corrected to a pointer pointing to the segment @, and the pointer of the segment ■ is made the chain end data.

In addition, in the above embodiment, only the movement of the wiring to the next wiring layout grid was explained, but there is no need to repeatedly apply the present invention to the wiring data after the movement within the permissible limit. unhindered.

〔Effect of the invention〕

As is clear from the above description, according to the present invention,
By effectively utilizing the inter-wire information added to the wiring data generated using conventional techniques, the wires in the rough wiring area are moved, so the probability of short-circuiting between adjacent wires can be reduced. Helps improve LSI yield and reliability.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a computer system implementing the present invention, Fig. 2 is a diagram showing a processing flow of the present invention, Fig. 3 is a diagram showing a segment list and a segment start pointer, and Fig. 4 is a diagram showing a semiconductor substrate. Figures 5 and 6 show wiring examples and segment start pointers showing the relationship thereto.
The figure is a diagram showing movement in the example shown in FIGS. 3 and 4. 50 is a segment list, 52 is a segment start pointer, and 54 is an example of wiring on a semiconductor substrate. In FIGS. 1 to 4, 20 is a CPU. 22 is the main memory, 24 is the disk device, 26 is the display device, 28 is the lotus, 30 is the keyboard, figure! jl play 1 yen 64Tυsugiλ c7/7 Togunut (From-To) Tagun/F Sozu L 汲v1〆Tozu 7-Tohoinota wo IG
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Claims (1)

[Claims] (1) Read the wiring position display data for each wiring that connects each element formed on the semiconductor substrate and exists on the same wiring layout grid position using the access pointer assigned to each wiring position. In the CAD system, the wiring position display data is read out using the corresponding access pointer, and the data of the wiring section in the wiring position display data corresponding to the wirings on both sides on the semiconductor substrate are compared. If the wiring corresponding to the wiring position display data is moved by the unit wiring arrangement grid spacing on the semiconductor substrate and the adjacent wirings are still adjacent to each other at an interval of one unit wiring arrangement grid spacing or more, then An LSI wiring changing method, characterized in that the access pointer of the wiring position display data of the wiring to be moved is changed to the access pointer of the wiring placement grid that is one adjacent in the movement direction.