Power rail for preventing DC electromigration

摘要

A method is disclosed that includes the operations outlined below. A first criteria is determined to be met when directions of a first current and a second current around a first end and a second end of a metal segment respectively are opposite, in which the metal segment is a part of a power rail in at least one design file of a semiconductor device and is enclosed by only two terminal via arrays. A second criteria is determined to be met when a length of the metal segment is not larger than a electromigration critical length. The metal segment is included in the semiconductor device with a first current density limit depending on the length of the metal segment when the first and the second criteria are met.

主权项

1. A method of making a semiconductor device comprising a device portion and a metal layer formed on the device portion and connected to the device portion, wherein the metal layer includes a power rail providing power to an integrated circuit component in the device portion, wherein the method for forming the power rail comprises steps of:
determining that a first criterion is met when directions of a first current and a second current around a first end and a second end of a metal segment respectively are opposite by using a computer, wherein the metal segment is a part of a power rail in at least one design file of a semiconductor device and is enclosed by two terminal via arrays; determining that a second criterion is met when a length of the metal segment is not larger than an electromigration critical length by using a computer; including the metal segment in the at least one design file with a first current density limit depending on the length of the metal segment when the first and the second criteria are met by using a computer; and fabricating, by using a fabrication system, the semiconductor device according to the at least one design file.