Photo alignment mark for a gate last process

摘要

A semiconductor device is provided which includes a semiconductor substrate having a first region and a second region, the first and second regions being isolated from each other, a plurality of transistors formed in the first region, an alignment mark formed in the second region, the alignment mark having a plurality of active regions in a first direction, and a dummy gate structure formed over the alignment mark, the dummy gate structure having a plurality of lines in a second direction different from the first direction.

主权项

1. A method for fabricating a semiconductor device, comprising:
providing a semiconductor substrate having a first region and a second region; forming an alignment mark in the first region, the alignment mark having a plurality of active regions in a first direction and an isolation structure disposed between adjacent active regions; forming a plurality of transistors in the second region including forming a first dummy gate structure for each transistor and a second dummy gate structure over the alignment mark, the second dummy gate structure having a plurality of lines in a second direction different from the first direction; and performing a gate last process to remove the first dummy gate structure of each transistor and replace it with a metal gate.