Granted Patent B2

US 7,981,808 · App. 12/241,139 · Granted Jul 19, 2011

Abstract

Claims (16)

1. A method of forming a gate dielectric layer, the method comprising:

depositing a first dielectric layer over a semiconductor substrate by introducing oxygen plasma in a chamber of a tool from a remote plasma block of the tool and introducing a metal into the chamber from a metal source so as to form the first dielectric be a metal oxide;

performing a plasma nitridation of the first dielectric layer in the chamber of the tool to form a nitrided dielectric layer by introducing nitrogen plasma into the chamber from the remote plasma block;

after performing the plasma nitridation of the first dielectric layer, before any anneal occurring after the step of forming the first dielectric layer, and without removing the semiconductor substrate from the chamber of the tool, depositing a second dielectric layer on the nitrided dielectric layer using oxygen plasma from the remote plasma block and metal from the metal source so as to form the second dielectric layer to be the metal oxide;

performing a plasma nitridation of the second dielectric layer without removing the semiconductor substrate from the chamber of the tool to form a second nitrided dielectric layer by introducing nitrogen plasma into the chamber from the remote plasma block; and

annealing the first and second nitrided dielectric layers after the step of performing a plasma nitridation of the second dielectric layer.

2. The method of claim 1 , wherein the step of depositing the dielectric layer comprises a process selected from the group consisting of plasma enhanced atomic layer deposition (PE-ALD) and plasma enhanced chemical vapor deposition (PE-CVD).

3. The method of claim 1 , wherein the step of depositing the first dielectric layer comprises forming the metal oxide layer comprising an element selected from hafnium, zirconium, and lanthanum.

4. The method of claim 1 , wherein the step of forming the first dielectric layer occurs at approximately room temperature.

5. A method of forming a gate dielectric layer comprising:

depositing a first hafnium oxide layer over a semiconductor substrate in a chamber using a first oxygen plasma introduced into the chamber from a remote plasma block coupled to an oxygen source and a first precursor containing hafnium;

performing a first in-situ plasma nitridation of the first dielectric layer by introducing a first nitrogen plasma into the chamber from the remote plasma block coupled to a nitrogen source to form a first nitrided dielectric layer;

depositing, in-situ, a second dielectric layer over the first dielectric layer using a second oxygen plasma introduced into the chamber from a remote plasma block and a second precursor containing hafnium after the step of performing the first in-situ plasma nitridation and before any anneal occurring after forming the first hafnium oxide layer;

performing a second in-situ plasma nitridation of the second dielectric layer by introducing a second nitrogen plasma into the chamber from the remote plasma block to form a second nitrided dielectric layer; and

annealing the first nitrided dielectric layer and the second nitrided dielectric layer, wherein the gate dielectric layer comprises the first nitrided dielectric layer and the second nitrided dielectric layer.

6. The method of claim 5 , wherein the steps of depositing the first dielectric layer and depositing the second dielectric layer are performed using the same processes.

Assignments (16)