Insulator, capacitor with the same and fabrication method thereof, and method for fabricating semiconductor device

1. A method for fabricating a capacitor, comprising:

forming a first electrode;

forming an insulator having a laminate structure in which aluminum oxide (Al 2 O 3 ) layers and hafnium oxide (HfO 2 ) layers are laminated on the first electrode alternately in an iterative manner; and

forming a second electrode on the insulator,

wherein a portion of the laminate structure disposed on the first electrode outside the second electrode has a thickness that is less than or equal to a half of a total thickness of the laminate structure covered with the second electrode, and

wherein the insulator having the laminate structure is formed in the same chamber by an in-situ process in its entirety.

2. The method of claim 1 , wherein the aluminum oxide (Al2O3) layer and the hafnium oxide (HfO2) layer are formed using a plasma enhanced atomic layer deposition (PEALD) process.

3. The method of claim 2 , wherein the PEALD process is performed using one selected from the group consisting of Al(CH 3 ) 3 , Al(C 2 H 5 ) 3 , and an Al-containing compound as an aluminum source gas.

4. The method of claim 2 , wherein the PEALD process is performed using C 16 H 36 HfO 4 , TEMA-Hf (Tetrakis ethylmethyamino Hafnium), or Hf[N(CH 3 )(C 2 H 5 ) 4 ] as a hafnium source gas.

5. The method of claim 2 , wherein the PEALD process is performed using one of oxygen (O 2 ), water vapor (H 2 O), nitric oxide (N 2 O), and ozone (O 3 ) as a reaction gas.

6. The method of claim 2 , wherein the PEALD process is performed at temperatures of approximately 250° C. to approximately 350° C. under pressures of approximately 2 torr to approximately 5 torr.

7. The method of claim 1 , wherein the first electrode and the second electrode comprise one of a metal layer, a metal nitride layer, and a laminate layer thereof.

8. The method of claim 7 , wherein the metal layer comprises one of transition metal layers and the metal nitride layer comprises one of transition metal nitride layers.

9. A method for fabricating a semiconductor device, comprising:

forming a first insulating layer on a substrate;

forming a lower interconnection on the first insulating layer by depositing a metal layer to a thickness greater than a target thickness and polishing the metal layer;

forming a first electrode on the lower interconnection;

forming an insulator having a laminate structure in which aluminum oxide (Al 2 O 3 ) layers and hafnium oxide (HfO 2 ) layers are laminated on the first electrode alternately in an iterative manner;

forming a conductive layer on the insulator;

etching the conductive layer to form a second electrode;

etching the insulator such that the insulator is left to a predetermined thickness on the first electrode, such that a portion of the laminate structure disposed on the first electrode outside the second electrode has a thickness that is less than or equal to a half of a total thickness of the laminate structure covered with the second electrode;

forming a second insulating layer on the substrate including the second electrode and the insulator;

forming a via connected to each of the first and second electrodes in the second insulating layer; and

forming an upper interconnection connected to the via on the second insulating layer.

10. The method of claim 9 , wherein said etching of the insulator is performed such that the left thickness of the insulator is approximately ¼ to approximately 2/4 of the total thickness of the insulator.

11. The method of claim 9 , wherein the first electrode is formed of a CVD (Chemical Vapor Deposition)-TiN layer.

12. The method of claim 9 , wherein the aluminum oxide (Al2O3) layer and the hafnium oxide (HfO2) layer are formed using a plasma enhanced atomic layer deposition (PEALD) process.

13. The method of claim 12 , wherein the PEALD process is performed using one selected from the group consisting of Al(CH 3 ) 3 , Al(C 2 H 5 ) 3 , and an Al-containing compound as an aluminum source gas.

14. The method of claim 12 , wherein the PEALD process is performed using C 16 H 36 HfO 4 , TEMA-Hf (Tetrakis ethylmethyamino Hafnium), or Hf[N(CH 3 )(C 2 H 5 ) 4 ] as a hafnium source gas.

15. The method of claim 12 , wherein the PEALD process is performed using one of oxygen (O 2 ), water vapor (H 2 O), nitric oxide (N 2 O), and ozone (O 3 ) as a reaction gas.

16. The method of claim 12 , wherein the PEALD process is performed at temperatures of approximately 250° C. to approximately 350° C. under pressures of approximately 2 torr to approximately 5 torr.

17. The method of claim 9 , wherein the insulator having the laminate structure is formed in the same chamber by an in-situ process in its entirety.

18. The method of claim 9 , wherein the first electrode and the second electrode comprise one of a metal layer, a metal nitride layer, and a laminate layer thereof.

19. The method of claim 18 , wherein the metal layer comprises one of transition metal layers and the metal nitride layer comprises one of transition metal nitride layers.

20. The method of claim 9 , wherein the lower interconnection is formed of aluminum.

21. A method for fabricating a semiconductor device, comprising:

forming a first electrode;

forming an insulator having a laminate structure in which two or more aluminum oxide (Al2O3) layers and two or more hafnium oxide (HfO2) layers are laminated alternately in an iterative manner and having a bottom layer and a top layer;

forming a second electrode on the insulator, wherein an upper surface of the bottom layer has a greater surface area than an upper surface of the top layer such that a portion of the bottom layer extends outside the top layer;

an upper surface of at least one layer of the two or more aluminum oxide (Al2O3) layers and the two or more hafnium oxide (HfO2) layers has a substantially equal surface area as the upper surface of the top layer; and

an upper surface of at least one other layer of the two or more aluminum oxide (Al2O3) layers and the two or more hafnium oxide (HfO2) layers has a substantially equal surface area as the upper surface of the bottom layer, such that a portion of the laminate structure disposed on the bottom layer outside the top layer has a thickness that is less than a portion of the laminate structure covered with the top layer.

22. The method of claim 21 , wherein either one of the Al 2 O 3 layer or the HfO 2 layer is formed using a plasma enhanced atomic layer deposition (PEALD) process.

23. The method of claim 21 , wherein the first electrode and the second electrode comprise one of a metal layer, a metal nitride layer, and a laminate layer thereof.

24. The method of claim 21 , wherein the first electrode and the second electrode are formed of different materials.