Variable rotational assignment of interconnect levels in integrated circuit fabrication
AssigneeLucent Technologies Inc.
InventorsThaddeus John Gabara, Tarek Chaker Jomaa
Life of this patent
Estimating the term…
Abstract
Integrated circuit fabrication techniques are provided which allow non-horizontal/non-vertical wires to traverse the entire chip surface, rather than just the corners as in the conventional Manhattan geometry, while interconnecting circuit points. This is achieved by employing a variable rotational assignment methodology with respect to the interconnect layers or levels during the IC fabrication operation. These techniques thus eliminate the litho step problem, reduce interconnect distances and lessen the influence of capacitance interaction between interconnect wires.
Claims14
Apparatus for use in fabricating at least a portion of an integrated circuit, the apparatus comprising:
- at least one processor operative to:
- (i) assign one or more interconnect lines associated with the integrated circuit which are non-horizontal and non-vertical to at least one metal mask layer separate from at least another metal mask layer assigned to at least one of horizontal interconnect lines and vertical interconnect lines;
- (ii) rotate each of the one or more non-horizontal/non-vertical interconnect lines from an original orientation by a predetermined angle determined by the original line orientation so that the one or more non-horizontal/non-vertical interconnect lines are at least one of horizontally and vertically oriented;
- and
- a mask printing device responsive to the at least one processor and operative to print the one or more rotated non-horizontal/non-vertical interconnect lines on the at least one metal mask layer assigned thereto.
An integrated circuit, at least a portion of the integrated circuit formed according to a fabrication method comprising the steps of:
- assigning one or more interconnect lines associated with the integrated circuit which are non-horizontal and non-vertical to at least one metal mask layer separate from at least another metal mask layer assigned to at least one of horizontal interconnect lines and vertical interconnect lines;
- rotating each of the one or more non-horizontal/non-vertical interconnect lines from an original orientation by a predetermined angle determined by the original line orientation so that the one or more non-horizontal/non-vertical interconnect lines are at least one of horizontally and vertically oriented;
- printing the one or more rotated non-horizontal/non-vertical interconnect lines on the at least one metal mask layer assigned thereto;
- rotating the at least one printed metal mask layer so that each of the one or more non-horizontal/non-vertical interconnect lines is returned to its original orientation;
- and
- using the rotated metal mask layer to expose a corresponding metal layer of the integrated circuit.
An integrated circuit, the integrated circuit comprising one or more metal layers, wherein at least one of the one or more metal layers includes only wires which are non-horizontally and non-vertically oriented.
Dependencies are inferred from the claim text.