Method of forming a capacitor of an integrated circuit device

1. A method of forming a capacitor of an integrated circuit device, the capacitor comprising a lower electrode, an upper electrode, and a dielectric stack therebetween, comprising the steps of:

a) adsorbing a metal compound on the lower electrode by using a gaseous metal compound;

b) purging a physisorbed metal compound on the lower electrode by using an inert gas;

c) oxidizing the metal compound adsorbed on the lower electrode to form a metal oxide;

d) purging a gaseous product formed by oxidizing the metal compound;

e) repeating the steps a) to d) to form a diffusion barrier layer of the metal oxide;

f) performing a UV-O3 treatment on the diffusion barrier layer;

g) forming a dielectric layer comprised of Ta 2 O 5 on the diffusion barrier layer; and

h) performing a heat treatment for the dielectric layer comprised of Ta 2 O 5 in an oxygen atmosphere,

wherein the dielectric stack comprising the diffusion barrier layer and the dielectric layer formed on a surface of the lower electrode has an equivalent silicon oxide layer thickness of about 25 Å.

2. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein the steps a) to e) are performed in a single atomic layer deposition chamber.

3. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein the metal compound gas is trimethyl aluminum or triethyl aluminum.

4. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein the metal oxide is Al 2 O 3 .

5. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein oxidizing the metal compound is performed using an oxygen gas selected from the group consisting of H 2 O, O 3 , O 2 plasma, N 2 O, and their mixtures.

6. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein a thickness of the diffusion barrier layer is less than about 30 Å.

7. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein a thickness of the dielectric layer is less than about 50 Å.

8. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein the capacitor is a cell capacitor of a dynamic random access memory.

9. A method of forming a capacitor of an integrated circuit device as claimed in claim 1 , wherein the lower electrode is a polysilicon layer.

10. A method of forming a capacitor of an integrated circuit device, the capacitor comprising a lower electrode, an upper electrode, and a dielectric stack therebetween, comprising the steps of:

a) preparing a wafer on which the lower electrode is formed in a reaction chamber;

b) providing a gaseous metal compound to the reaction chamber for adsorbing the metal compound on a surface of the lower electrode of the wafer;

c) purging a physisorbed metal compound on the surface of the lower electrode by using an insert gas;

d) repeating the steps b) to c) for forming a metal compound layer;

e) oxidizing the metal compound layer for forming a diffusion barrier layer of a metal oxide;

f) performing a UV-O3 treatment on the diffusion barrier layers

g) forming a dielectric layer comprised of Ta 2 O 5 on the diffusion barrier layer; and

h) performing a heat treatment for the dielectric layer comprised of Ta 2 O 5 in an oxygen atmosphere,

wherein the dielectric stack comprising the diffusion barrier layer and the dielectric layer formed on a surface of the lower electrode has an equivalent silicon oxide layer thickness of about 25 Å.

11. A method of forming a dielectric stack of an integrated circuit device in a reaction chamber, comprising the steps of:

a) supplying a gaseous metal reactant to the reaction chamber, the reaction chamber including a substrate;

b) removing a physisorbed metal reactant from the substrate;

c) oxidizing the substrate having a chemisorbed metal reactant with an oxidizing agent for forming a diffusion barrier layer;

d) removing gaseous products produced by oxidizing the substrate;

e) performing a UV-O3 treatment on the diffusion barrier layer; and

f) forming a dielectric layer on the diffusion barrier layer,

wherein the dielectric stack comprising the diffusion barrier layer and the dielectric layer formed on a surface of the lower electrode has an equivalent silicon oxide layer thickness of about 25 Å.

12. A method as claimed in claim 11 , wherein the steps a) to d) are repeated until the diffusion barrier layer has a predetermined thickness.

13. A method as claimed in claim 12 , wherein the predetermined thickness of the diffusion barrier layer is about 20 Å.

14. A method as claimed in claim 11 , wherein the diffusion barrier layer is an aluminum oxide layer and the dielectric layer is a tantalum oxide layer.

15. A method as claimed in claim 14 , further comprising the step of treating the dielectric layer with UV-O3.

16. A method as claimed in claim 14 , further comprising the step of heat treatment of the dielectric layer.

17. A method as claimed in claim 11 , wherein the gaseous metal reactant is trimethyl aluminum or triethyl aluminum.

18. A method as claimed in claim 11 , wherein the oxidizing agent is selected from the group consisting of H 2 O, O 3 , O 2 plasma, N 2 O, and their mixtures.