Method of forming ultra-thin SiN film by plasma CVD
A method of forming an ultra-thin SiN film includes: supplying a Si source gas into a reactor in which a substrate is placed on a susceptor; supplying an N source gas into the reactor at a flow rate which is at least 300 times that of the Si source gas; applying an RF power between an upper electrode and the susceptor in the reactor; and depositing an ultra-thin SiN film on the substrate.
1. A method of forming an ultra-thin SiN film comprising the steps of:
supplying a Si source gas into a reactor in which a substrate is placed on a susceptor, wherein the flow rate of the Si source gas is 10 sccm or less;
supplying an N source gas into the reactor at a flow rate which is over 1,000 times that of the Si source gas;
applying an RF power between an upper electrode and the susceptor in the reactor; and
depositing an ultra-thin SiN film on the substrate, wherein the step of depositing the ultra-thin SiN film comprises controlling a deposition rate of the film at 55 nm/min or less by controlling the step of supplying the Si source gas and the step of supplying the N source gas.
2. The method according to claim 1 , wherein the Si source gas is SiH 4 .
3. The method according to claim 1 , wherein the N source gas is N 2 .
4. The method according to claim 1 , wherein the step of depositing the ultra-thin SiN film deposits the film at a thickness of less than 15 nm.
5. The method according to claim 1 , wherein the step of supplying the N source gas further comprises supplying NH 3 .
6. The method according to claim 1 , wherein the ultra-thin SiN film obtained from the step of depositing the ultra-thin SiN film has a uniformity of ±3% or less.
7. The method according to claim 1 , wherein in the step of supplying the N source gas, the N source gas is supplied at a flow rate which is no less than 2,000 times that of the Si source gas.
8. The method according to claim 5 , wherein the NH 3 is supplied at a flow rate of 10 sccm or less.
9. The method according to claim 8 , wherein the ultra-thin SiN film obtained from the step of depositing the ultra-thin SiN film has a leakage current of 10 −6 A/cm 2 or less at 2 MV/cm.
10. A method of forming an ultra-thin SiN film comprising the steps of:
supplying a Si source gas into a reactor in which a substrate is placed on a susceptor, wherein the flow rate of the Si source gas is 10 sccm or less;
supplying an N source gas into the reactor at a flow rate which is at least 300 times that of the Si source gas;
applying an RF power between an upper electrode and the susceptor in the reactor; and
depositing an ultra-thin SiN film on the substrate, wherein the step of depositing the ultra-thin SiN film comprises controlling a deposition rate of the film at 55 nm/min or less by controlling the step of supplying the Si source gas and the step of supplying the N source gas,
wherein the RF power is a combination of high-frequency RF power of 1 MHz to 27.13 MHz and low-frequency RF power of less than 1 MHz.
11. The method according to claim 10 , wherein the high-frequency RF power is applied at 150-1,000 W and the low-frequency RF power is applied at no more than 350 W.
12. The method according to claim 10 , wherein in the step of supplying the N source gas, the N source gas is supplied at a flow rate which is over 1,000 times that of the Si source gas.
13. The method according to claim 12 , wherein in the step of supplying the N source gas, the N source gas is supplied at a flow rate which is no less than 2,000 times that of the Si source gas.