Preventing FIN Erosion and Limiting Epi Overburden in FinFET Structures by Composite Hardmask

摘要

A FinFET structure is formed by forming a hardmask layer on a substrate including a silicon-containing layer on an insulating layer. The hardmask layer includes first, second and third layers on the silicon-containing layer. An array of fins is formed from the hardmask layer and the silicon-containing layer. A gate is formed covering a portion but not all of a length of each of the array of fins. The portion covers each of the fins in the array. The gate defines source/drain regions on either side of the gate. A spacer is formed on each side of the gate, the forming of the spacer performed to remove the third layer from portions of the fins in the source/drain regions. The second layer of the hardmask layer is removed from the portions of the fins in the source/drain regions, and the fins in the source/drain regions are merged.

主权项

1. A method for forming a FinFET structure, comprising:
forming a hardmask layer on a substrate, wherein the substrate comprises a silicon-containing layer on an insulating layer, wherein the hardmask layer comprises first, second and third layers, and wherein the first layer is formed on and in contact with the silicon-containing layer, the second layer is formed on the first layer, and the third layer is formed on the second layer; forming an array of fins from the hardmask layer and the silicon-containing layer; forming a gate covering a portion but not all of a length of each of the array of fins, the portion covering each of the fins in the array, the gate defining source/drain regions on either side of the gate; forming a spacer on each side of the gate, the forming of the spacer performed to remove the third layer from portions of the fins in the source/drain regions; removing the second layer of the hardmask layer from the portions of the fins in the source/drain regions; and merging the fins in the source/drain regions to create merged fins in the source/drain regions.