Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.

Abstract: A method includes forming isolation regions extending into a semiconductor substrate, wherein semiconductor strips are located between the isolation regions, and forming a dielectric dummy strip between the isolation regions, recessing the isolation regions. Some portions of the semiconductor strips protrude higher than top surfaces of the recessed isolation regions to form protruding semiconductor fins, and a portion of the dielectric dummy strip protrudes higher than the top surfaces of the recessed isolation regions to form a dielectric dummy fin. The method further includes etching the dielectric dummy fin so that a top width of the dielectric dummy fin is smaller than a bottom width of the dielectric dummy fin. A gate stack is formed on top surfaces and sidewalls of the protruding semiconductor fins and the dielectric dummy fin.

Abstract: A method includes forming isolation regions extending into a semiconductor substrate, wherein semiconductor strips are located between the isolation regions, and forming a dielectric dummy strip between the isolation regions, recessing the isolation regions. Some portions of the semiconductor strips protrude higher than top surfaces of the recessed isolation regions to form protruding semiconductor fins, and a portion of the dielectric dummy strip protrudes higher than the top surfaces of the recessed isolation regions to form a dielectric dummy fin. The method further includes etching the dielectric dummy fin so that a top width of the dielectric dummy fin is smaller than a bottom width of the dielectric dummy fin. A gate stack is formed on top surfaces and sidewalls of the protruding semiconductor fins and the dielectric dummy fin.

Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.

Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.

Abstract: A method includes forming isolation regions extending into a semiconductor substrate, wherein semiconductor strips are located between the isolation regions, and forming a dielectric dummy strip between the isolation regions, recessing the isolation regions. Some portions of the semiconductor strips protrude higher than top surfaces of the recessed isolation regions to form protruding semiconductor fins, and a portion of the dielectric dummy strip protrudes higher than the top surfaces of the recessed isolation regions to form a dielectric dummy fin. The method further includes etching the dielectric dummy fin so that a top width of the dielectric dummy fin is smaller than a bottom width of the dielectric dummy fin. A gate stack is formed on top surfaces and sidewalls of the protruding semiconductor fins and the dielectric dummy fin.

Abstract: A method includes forming isolation regions extending into a semiconductor substrate, wherein semiconductor strips are located between the isolation regions, and forming a dielectric dummy strip between the isolation regions, recessing the isolation regions. Some portions of the semiconductor strips protrude higher than top surfaces of the recessed isolation regions to form protruding semiconductor fins, and a portion of the dielectric dummy strip protrudes higher than the top surfaces of the recessed isolation regions to form a dielectric dummy fin. The method further includes etching the dielectric dummy fin so that a top width of the dielectric dummy fin is smaller than a bottom width of the dielectric dummy fin. A gate stack is formed on top surfaces and sidewalls of the protruding semiconductor fins and the dielectric dummy fin.

Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.

Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.

Abstract: A method includes forming isolation regions extending into a semiconductor substrate, wherein semiconductor strips are located between the isolation regions, and forming a dielectric dummy strip between the isolation regions, recessing the isolation regions. Some portions of the semiconductor strips protrude higher than top surfaces of the recessed isolation regions to form protruding semiconductor fins, and a portion of the dielectric dummy strip protrudes higher than the top surfaces of the recessed isolation regions to form a dielectric dummy fin. The method further includes etching the dielectric dummy fin so that a top width of the dielectric dummy fin is smaller than a bottom width of the dielectric dummy fin. A gate stack is formed on top surfaces and sidewalls of the protruding semiconductor fins and the dielectric dummy fin.

Abstract: An embodiment device includes a first source/drain region over a semiconductor substrate and a dummy fin adjacent the first source/drain region. The dummy fin comprising: a first portion comprising a first film and a second portion over the first portion, wherein the second portion comprises: a second film; and a third film. The third film is between the first film and the second film, and the third film is made of a different material than the first film and the second film. A width of the second portion-is less than a width of the first portion. The device further comprises a gate stack along sidewalls of the dummy fin.