Cross-fill pattern for metal fill levels, power supply filtering, and analog circuit shielding
View Patent ↗A cross-fill metal fill pattern technique is provided such that portions of a metal fill pattern are patterned to accomplish a secondary function. For instance, in the exemplary embodiments, ever other trace or line of interdigitated fingers is routed to a ground, while the interceding traces or lines of interdigitated fingers are routed to a power supply. In this way, a capacitor function is formed across the power supply, providing additional decoupling for the power supply. Moreover, a suitably tight cross-fill metal fill pattern (i.e., higher density of metal) provides an electrical shielding function for electromagnetic radiation passing therethrough.
1. An integrated circuit including a metal fill pattern comprising:
a first plurality of curved metal traces electrically connected to a power supply pad;
a second plurality of curved metal traces electrically connected to a ground pad; and
over-routing signal bearing metal lines over said first plurality of metal traces and said second plurality of metal traces;
wherein said second plurality of metal traces are interdigitated between said first plurality of metal traces to form a purposeful inter-metal capacitance therebetween and to provide electromagnetic shielding to protect circuitry therebelow from said over-routed signal bearing metal lines.
2. The integrated circuit including a metal fill pattern according to claim 1 , wherein:
said circuitry therebelow includes an analog circuit.
3. The integrated circuit including a metal fill pattern according to claim 1 , further comprising:
a first plurality of traces crossing each of said first plurality of metal traces; and
a second plurality of traces crossing each of said second plurality of metal traces.
4. The integrated circuit including a metal fill pattern according to claim 3 , wherein:
said first plurality of traces each form a perpendicular angle with respect to an electrically connected one of said first plurality of metal traces.
5. The integrated circuit including a metal fill pattern according to claim 4 , wherein:
said second plurality of traces each form a perpendicular angle with respect to an electrically connected one of said second plurality of metal traces.
6. The integrated circuit including a metal fill pattern according to claim 4 , wherein:
a portion of said first plurality of metal traces connected to a number of said first plurality of traces forms a straight line.
7. The integrated circuit including a metal fill pattern according to claim 6 , wherein:
another portion of said first plurality of metal traces connected to others of said first plurality of traces forms a curving line.
8. The integrated circuit including a metal fill pattern according to claim 4 , wherein:
a portion of said first plurality of metal traces connected to a number of said first plurality of traces forms a curving line.
9. The integrated circuit including a metal fill pattern according to claim 1 , wherein:
said metal fill pattern forms a coverage density of at least 50%.
10. The integrated circuit including a metal fill pattern according to claim 1 , wherein:
said first plurality of metal traces and said second plurality of metal traces are linear.
11. The integrated circuit including a metal fill pattern according to claim 10 , wherein:
said first plurality of metal traces and said second plurality of metal traces run along a generally straight line.
12. An integrated circuit including a metal fill pattern comprising:
a first plurality of various length metal traces electrically connected to a power supply pad;
a second plurality of various length metal traces electrically connected to a ground pad; and
over-routing signal bearing metal lines over said first plurality of metal traces and said second plurality of metal traces;
wherein said second plurality of metal traces are interdigitated between said first plurality of metal traces to form a purposeful inter-metal capacitance therebetween and to provide electromagnetic shielding to protect circuitry therebelow from said over-routed signal bearing metal lines.
13. The integrated circuit including a metal fill pattern according to claim 12 , wherein:
said circuitry therebelow includes an analog circuit.
14. The integrated circuit including a metal fill pattern according to claim 12 , further comprising:
a first plurality of traces crossing each of said first plurality of metal traces; and
a second plurality of traces crossing each of said second plurality of metal traces.
15. The integrated circuit including a metal fill pattern according to claim 14 , wherein:
said first plurality of traces each form a perpendicular angle with respect to an electrically connected one of said first plurality of metal traces.
16. The integrated circuit including a metal fill pattern according to claim 15 , wherein:
said second plurality of traces each form a perpendicular angle with respect to an electrically connected one of said second plurality of metal traces.
17. The integrated circuit including a metal fill pattern according to claim 15 , wherein:
a portion of said first plurality of metal traces connected to a number of said first plurality of traces forms a straight line.
18. The integrated circuit including a metal fill pattern according to claim 17 , wherein:
another portion of said first plurality of metal traces connected to others of said first plurality of traces forms a curving line.
19. The integrated circuit including a metal fill pattern according to claim 15 , wherein:
a portion of said first plurality of metal traces connected to a number of said first plurality of traces forms a curving line.
20. The integrated circuit including a metal fill pattern according to claim 12 , wherein:
said metal fill pattern forms a coverage density of at least 50%.
21. The integrated circuit including a metal fill pattern according to claim 20 , wherein:
said first plurality of metal traces and said second plurality of linear metal traces run along a generally straight line.
22. The integrated circuit including a metal fill pattern according to claim 12 , wherein:
said first plurality of metal traces and said second plurality of metal traces are linear.