Method of forming capacitors containing tantalum

A method of forming a capacitor comprising:

• forming a first capacitor plate comprising polysilicon;
• forming a silicon nitride layer over the polysilicon;
• forming a first layer as a dielectric over the silicon nitride layer, the first layer comprising tantalum;
• forming a second layer over the first layer, the second layer comprising at least some of the tantalum of the first layer and nitrogen;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and having an exposed outer surface;
• forming a second layer over the first layer by exposing the outer surface of the first layer to a nitrogen-comprising gas, the second layer comprising some of the tantalum of the first layer and some of the nitrogen of the nitrogen-comprising gas;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and having an exposed outer surface;
• forming a second layer over the first layer by exposing the outer surface of the first layer to a nitrogen-comprising gas at a temperature of from about 350.degree. C. to about 900.degree. C., and for a time of from about 30 seconds to about 10 minutes, the second layer comprising tantalum and nitrogen;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a tantalum-comprising layer as a dielectric over the first capacitor plate, the tantalum-comprising layer comprising oxygen and being substantially void of carbon;
• forming a barrier layer over the tantalum-comprising layer;
• forming a metal layer comprising carbon over the barrier layer;
• forming a second capacitor plate over the metal layer;
• and
• processing the metal layer at a sufficient temperature to diffuse carbon from the metal layer, the barrier layer substantially preventing such carbon from diffusing into the tantalum-comprising layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a tantalum-comprising layer as a dielectric over the first capacitor plate, the tantalum-comprising layer comprising oxygen;
• forming a barrier layer over the tantalum-comprising layer, the barrier layer comprising less than 10 volume percent of carbon and comprising some of the tantalum of the tantalum-comprising layer;
• and
• forming a second capacitor plate over the barrier layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and oxygen;
• annealing the exposed first layer in the presence of an ambient comprising a nitrogen-comprising gas containing at least one compound selected from a group consisting of ammonia, hydrazine, NF.sub.3 and hydrazoic acid;
• the annealing forming a second layer over the first layer comprising some of the tantalum of the first layer;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and having an exposed outer surface;
• forming a second layer over the first layer by exposing the outer surface of the first layer to a nitrogen-comprising gas consisting essentially of hydrazine at a temperature of from about 350.degree. C. to about 600.degree. C., the second layer comprising tantalum and nitrogen;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and having an exposed outer surface;
• forming a second layer over the first layer by exposing the outer surface of the first layer to a nitrogen-comprising gas consisting essentially of ammonia at a temperature of from about 600.degree. C. to about 900.degree. C., the second layer comprising tantalum and nitrogen;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and oxygen;
• annealing the exposed first layer at a temperature of from about 350.degree. C. to about 600.degree. C. in the presence of an ambient comprising a nitrogen-comprising gas consisting essentially of hydrazine, the annealing forming a second layer over the first layer;
• and
• forming a second capacitor plate over the second layer.

A method of forming a capacitor comprising:

• forming a first capacitor plate;
• forming a first layer as a dielectric over the first capacitor plate, the first layer comprising tantalum and oxygen;
• annealing the exposed first layer at a temperature of from about 600.degree. C. to about 900.degree. C. in the presence of an ambient comprising a nitrogen-comprising gas consisting essentially of ammonia, the annealing forming a second layer over the first layer;
• and
• forming a second capacitor plate over the second layer.