Method of plasma etching and method of fabricating semiconductor device using the same
Disclosed are a method of plasma etching and a method of fabricating a semiconductor device including the same. The method of plasma etching includes loading a substrate including an etch target onto a first electrode in a chamber, the chamber including the first electrode and a second electrode arranged to face each other, and etching the target. The etching the target includes applying a plurality of RF powers to one of the first and second electrodes. The plurality of RF powers may include a first RF power having a first frequency in a range from about 40 MHz to about 300 MHz, a second RF power having a second frequency in a range from about 100 kHz to about 10 MHz, and a third RF power having a third frequency in a range from about 10 kHz to about 5 MHz.
1. A method of fabricating a semiconductor device, the method comprising:
forming a mold insulation layer on a substrate; and
performing a plasma etching process on the mold insulation layer to form an etched opening that penetrates at least a portion of the mold insulation layer,
the performing the plasma etching process including,
loading the substrate in a chamber, the substrate including an etching target, the chamber including a first electrode and a second electrode above the first electrode; and
etching the etching target, the etching the etching target including applying a plurality of RF powers to the first electrode,
wherein applying the plurality of RF powers comprises:
applying a first RF power having a first frequency to the first electrode, the first RF power pulsed to have a pulse frequency;
applying a second RF power having a second frequency lower than the first frequency to the first electrode, the second RF power pulsed to have the pulse frequency; and
applying a third RF power having a third frequency lower than the second frequency to the first electrode, the third RF power pulsed to have the pulse frequency, the third RF power being greater than at least one of the first RF power and the second RF power,
wherein the second RF power and the third RF power are simultaneously pulsed, with the initial application of the second and third RF powers occurring after at least one cycle of the first RF power.
2. The method of claim 1 , wherein the etched opening has an aspect ratio in a range from about 20:1 to about 100:1.
3. The method of claim 1 , further comprising:
forming a lower electrode in the opening; and
forming a filling pattern on the lower electrode in the opening.
4. The method of claim 3 , further comprising:
removing the mold insulation layer and the filling pattern to expose the lower electrode;
forming a dielectric layer on the lower electrode; and
forming an upper electrode layer on the dielectric layer.
5. The method of claim 1 , wherein the mold insulation layer includes a first layer and a second layer alternately stacked.
6. The method of claim 5 , further comprising:
forming a data storage pattern and a first semiconductor pattern in the opening;
forming a second semiconductor on the first semiconductor pattern in the opening;
forming a filling insulation layer on the second semiconductor in the opening; and
etching a portion of the mold insulation layer to form a trench adjacent to the opening.
7. The method of claim 6 , wherein the first layer and the second layer are formed by the trench to a first pattern and a second pattern respectively.
8. The method of claim 7 , further comprising:
removing the first layer to form a hollow space under the second pattern;
forming a blocking insulation layer and an electrode pattern in the hollow space; and
forming a device isolation layer in the trench.
9. The method of claim 1 , wherein
the first frequency is 60 MHz,
the second frequency is 2 MHz, and
the third frequency is 400 kHz.
10. The method of claim 1 , wherein applying the plurality of RF powers further comprises:
applying a fourth RF power having a fourth frequency greater than the second frequency and lower than the first frequency.
11. A method of fabricating a semiconductor device, the method comprising:
forming a mold insulation layer on a substrate; and
etching a portion of the mold insulation layer using a plurality of RF powers to form an opening in the mold insulation layer,
wherein etching the portion of the mold insulation layer comprises:
applying a first RF power having a first frequency to a chuck electrode receiving the substrate in a chamber, the first RF power modulated to have a first pulsed frequency;
applying a second RF power having a second frequency lower than the first frequency to a chuck electrode and being lower than the first RF power, the second RF power modulated to have a second pulsed frequency; and
applying a third RF power having a third frequency lower than the second frequency to a chuck electrode and being greater than the first RF power, the third RF power modulated to have a third pulsed frequency,
wherein the second and third RF powers are simultaneously pulsed, with the initial application of the second and the third RF powers occurring after at least one cycle of the first RF power.
12. The method of claim 11 , wherein the opening has an aspect ratio in a range from about 20:1 to about 100:1.
13. The method of claim 11 , wherein the first to third RF powers have a duty cycle of 50% to 70%.
14. The method of claim 11 , wherein
the first frequency is 60 MHz,
the second frequency is 9.8 MHz, and
the third frequency is 400 kHz.
15. The method of claim 11 , wherein
the first frequency is 60 MHz,
the second frequency is 2 MHz to 9.8 MHz, and
the third frequency is 400 kHz.
16. The method of claim 11 , further comprising:
forming a lower electrode in the opening; and
forming a filling pattern on the lower electrode in the opening.
17. The method of claim 16 , further comprising:
removing the mold insulation layer and the filling pattern to expose the lower electrode;
forming a dielectric layer on the lower electrode; and
forming an upper electrode layer on the dielectric layer.
18. The method of claim 11 , wherein the mold insulation layer includes a first layer and a second layer alternately stacked.
19. The method of claim 18 , further comprising:
forming a data storage pattern and a first semiconductor pattern in the opening;
forming a second semiconductor on the first semiconductor pattern in the opening;
forming a filling insulation layer on the second semiconductor in the opening; and
etching a portion of the mold insulation layer to form a trench adjacent to the opening,
wherein the first layer and the second layer are formed by the trench to a first pattern and a second pattern respectively.
20. The method of claim 19 , further comprising;
removing the first pattern to form a hollow space under the second pattern;
forming a blocking insulation layer and an electrode pattern in the hollow space; and
forming a device isolation layer in the trench.