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U. Glaeser

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TRACIF takes a CIF file as input and generates files containing geometrical objects (rectangles) defined<br />

by the canonical coordinates of each IC cell and mask layer as outputs. Thus, the outputs of TRACIF are<br />

lists of sorted rectangles according to the top edges from top to bottom. TRACIF can handle Manhattan<br />

shaped objects and consists of about 800 lines of C code. Therefore, TRACIF is capable to perform the<br />

layout description transformation hierarchically. Namely, TRACIF transforms a CIF file to the restricted<br />

format in a hierarchical way and makes different files for different cells and layers. This feature is desirable<br />

because most of the modern IC designs exploit the technique of design hierarchy. Within this design<br />

methodology, the layout extraction is only required once for each layout cell. Here, the results of transforming<br />

CIF file of IC chip that was designed using double metal CMOS process will be presented. The<br />

total number of rectangles before and after processing, as well as the CPU time needed for transforming<br />

this CIF file by TRACIF on Silicon Graphics Indy workstation are shown in Table 47.1.<br />

EXtrActor of Chip Critical Area (EXACCA)<br />

EXACCA takes the sorted rectangles and starts the critical area extraction by using the proposed algorithm.<br />

EXACCA can handle Manhattan-type objects and consists of about 2000 lines of C code. The<br />

outputs of EXACCA are lists of the critical areas for point or lithographic defects. Software tool GRAPH<br />

performs the visual presentation of the critical areas. Pictorial examples of the layouts and snapshots of<br />

the corresponding critical areas are shown in Figs. 47.12. and 47.13. Precision of a visual presentation<br />

© 2002 by CRC Press LLC<br />

TABLE 47.1 Processing Time and Number of Objects<br />

Before and After Transformation of CIF File by TRACIF<br />

IC Cell<br />

Rec. No.<br />

Before<br />

Processing<br />

Rec. No.<br />

After<br />

Processing<br />

CPU Time<br />

(s)<br />

buf.CO 394 394 1.164<br />

buf.ME 58 37 0.014<br />

buf.NP 203 14 0.033<br />

buf.NW 102 2 0.014<br />

buf.PO 44 41 0.017<br />

buf.PP 200 14 0.031<br />

buf.TO 414 40 0.130<br />

buf.VI 11 11 0.006<br />

chi.CO 2 2 0.006<br />

chi.ME 199 108 0.108<br />

chi.PO 4 4 0.006<br />

chi.VI 67 67 0.021<br />

exo.CO 63 63 0.027<br />

exo.ME 3 3 0.006<br />

exo.NP 35 2 0.006<br />

exo.NW 21 1 0.006<br />

exo.PO 45 21 0.009<br />

exo.PP 35 2 0.006<br />

exo.TO 73 18 0.012<br />

exo.VI 2 2 0.006<br />

ful.ME 30 9 0.007<br />

ful.PO 4 4 0.006<br />

ful.VI 6 6 0.006<br />

hal.CO 2 2 0.006<br />

hal.ME 88 58 0.025<br />

hal.PO 5 4 0.006<br />

hal.VI 27 27 0.008<br />

hig.ME 7 3 0.006<br />

hig.PA 1 1 0.006<br />

hig.VI 1 1 0.006

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