Patent ID: 11894461
Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A semiconductor device, comprising:
a semiconductor substrate;
a first transistor having a first threshold voltage, the first transistor comprising:
a first interfacial layer formed on the semiconductor substrate;
a first high-k dielectric layer formed on the first interfacial layer; and
a first conductive gate electrode layer formed on the first high-k dielectric layer; and
a second transistor having a second threshold voltage, the second transistor comprising:
a second interfacial layer formed on the semiconductor substrate;
a second high-k dielectric layer formed on the second interfacial layer; and
a second conductive gate electrode layer formed on the second high-k dielectric layer,
wherein at least one of the first high-k dielectric layer and the first interfacial layer, and at least one of the second high-k dielectric layer and the second interfacial layer are doped with:
a first dopant species,
a second dopant species, and
a third dopant species,
wherein at least one of the first dopant species and the second dopant species forms a first dipole element having a first polarity,
wherein the third dopant species forms a second dipole element having a second polarity,
wherein the first and second polarities are opposite,
wherein the first and second threshold voltages are different,
wherein the first transistor has a first concentration of the first dopant species at a first particular location in the at least one of the first high-k dielectric layer and the first interfacial layer and has a second concentration of the second dopant species at the first particular location in the at least one of the first high-k dielectric layer and the first interfacial layer,
wherein the second transistor has a third concentration of the first dopant species in a second particular location of at least one of the second high-k dielectric layer and the second interfacial layer and has a fourth concentration of the second dopant species in the second particular location of the at least one of the second high-k dielectric layer and the second interfacial layer, wherein the second particular location of the second transistor corresponds with the first particular location of the first transistor, and
wherein a first ratio of the first concentration to the second concentration is substantially equal to a second ratio of the third concentration to the fourth concentration, and wherein the first and second transistors have different conductivity types.