FinFET Formation with a Thermal Oxide Spacer Hard Mask Formed from Crystalline Silicon Layer

摘要

A semiconductor process and apparatus provide a FinFET device by forming a second single crystal semiconductor layer (19) that is isolated from an underlying first single crystal semiconductor layer (17) by a buried insulator layer (18); patterning and etching the second single crystal semiconductor layer (19) to form a single crystal mandrel (42) having vertical sidewalls; thermally oxidizing the vertical sidewalls of the single crystal mandrel to grow oxide spacers (52) having a substantially uniform thickness; selectively removing any remaining portion of the single crystal mandrel (42) while substantially retaining the oxide spacers (52); and selectively etching the first single crystal semiconductor layer (17) using the oxide spacers (52) to form one or more FinFET channel regions (92).