Low noise transistor and method of making same

A method of forming a semiconductor device, comprising:

• forming a gate stack over a semiconductor material, said gate stack including a gate dielectric formed over said semiconductor material and a gate electrode formed over said gate dielectric;
• forming a dielectric sidewall spacer over a sidewall of said gate stack;
• implanting source/drain dopants into said semiconductor material after forming said sidewall spacer;
• introducing fluorine into at least said gate electrode after forming said sidewall spacer, wherein the fluorine is introduced into some but not all n-channel transistors in the semiconductor device;
• and
• performing a anneal process after introducing said fluorine and after implanting said source/drain dopants.

A method of forming a field effect transistor, comprising:

• forming a gate stack over a semiconductor material, said gate stack including a gate dielectric formed over said semiconductor material and a gate electrode formed over said gate dielectric;
• forming a dielectric sidewall spacer over a sidewall of said gate stack;
• implanting source/drain dopants into said semiconductor material after forming said dielectric sidewall spacer;
• introducing a noise-reducing agent into at least said gate electrode after forming said dielectric sidewall spacer, wherein introducing said noise-reducing agent comprises implanting said noise-reducing agent at a dose greater than 5×1015 cm−2;
• and
• performing an anneal process after introducing said noise-reducing agent and after implanting said source/drain dopants.

A method of forming a field effect transistor, comprising:

• forming a gate stack over a semiconductor material, said gate stack including a gate dielectric formed over said semiconductor material and a gate electrode formed over said gate dielectric;
• forming a dielectric sidewall spacer over a sidewall of said gate stack;
• implanting source/drain dopants into said semiconductor material after forming said sidewall spacer;
• introducing fluorine into at least said gate electrode after forming said sidewall spacer, wherein said introducing said fluorine comprises implanting said fluorine at a dose greater than 5×1015 cm−2;
• and
• performing an anneal process after introducing said fluorine and after implanting said source/drain dopants.

A method of forming a field effect transistor, comprising:

• forming a gate stack over a semiconductor material, said gate stack including a gate dielectric formed over said semiconductor material and a gate electrode formed over said gate dielectric;
• forming a dielectric sidewall spacer over a sidewall of said gate stack;
• introducing source/drain dopants into said semiconductor material after forming said sidewall spacer;
• introducing a noise-reducing agent into at least said gate electrode after forming said sidewall spacer, wherein the introducing comprises implanting said noise-reducing agent at a dose greater than 5×1015 cm−2, wherein an energy of the implanting is about 10 keV and to about 20 keV, and wherein the gate dielectric has a thickness between about 3 nm to about 6 nm;
• and
• performing an anneal process after introducing said noise-reducing agent and after introducing said source/drain dopants.

A method of forming a field effect transistor, comprising:

• forming a gate stack over a semiconductor material, said gate stack including a gate dielectric formed over said semiconductor material and a gate electrode formed over said gate dielectric;
• forming a dielectric sidewall spacer over a sidewall surface of said gate stack;
• introducing source/drain dopants into said semiconductor material after forming said sidewall spacer;
• introducing fluorine into said semiconductor material after forming said sidewall spacer, wherein said introducing comprises implanting said fluorine at a dose greater than 5×1015 cm−2, wherein an energy of the implanting is about 10 keV and to about 20 keV, and wherein the gate dielectric has a thickness between about 3 nm to about 6 nm;
• and
• performing an anneal process after introducing said fluorine and after introducing said source/drain dopants.