Method of forming organosilicon oxide film and multilayer resist structure
A method of forming an organosilicon oxide film by plasma CVD includes: (i) adjusting a temperature of a susceptor on which a substrate is placed to lower than 300° C.; (ii) introducing at least tetraethylorthosilicate (TEOS) and oxygen into a reactor in which the susceptor is disposed; (iii) applying high-frequency RF power and low-frequency RF power; and (iv) thereby depositing an organosilicon oxide film on the substrate.
1. A method of forming a multilayer resist structure, comprising:
forming a first resist layer on a substrate;
forming an organosilicon oxide film as a mask on the first resist layer by a method comprising:
adjusting a temperature of a susceptor on which the substrate is placed to lower than 300° C.;
introducing at least tetraethylorthosilicate (TEOS) gas and oxygen-supplying gas into a reactor in which the susceptor is disposed, wherein the reactor is a capacitively-coupled plasma CVD reactor wherein a showerhead and the susceptor are disposed parallel to each other, wherein the TEOS gas is introduced at a flow rate of 60 to 80 sccm, and the oxygen-supplying gas is introduced at a flow rate of 1,400 to 2,600 sccm;
applying high-frequency RF power and low-frequency RF power between the showerhead and the susceptor, wherein the high-frequency RF power has a frequency of 10 MHz to 30 MHz and the low-frequency RF power has a frequency of 350 kHz to 500 kHz, the low-frequency RF power is 0.4 W/cm 2 to 0.6 W/cm 2 , and the high-frequency RF power is 0.1 W/cm 2 to 0.3 W/cm 2 ; and
thereby depositing the organosilicon oxide film on the substrate; and
forming a second resist layer on the organosilicon oxide film.
2. The method according to claim 1 , wherein the introducing step further comprises introducing an inert gas.
3. The method according to claim 2 , wherein a flow rate of the TEOS, that of the oxygen, and that of the inert gas satisfies the following inequity: TEOS<inert gas<oxygen.
4. The method according to claim 1 , wherein the temperature of the susceptor is about 250° C. or lower.
5. The method according to claim 1 , wherein the depositing step is controlled to deposit the organosilicon oxide film at a growth rate of about 400 nm/minutes or less.
6. The method according to claim 1 , wherein a thickness of the organosilicon oxide film is about 30 nm to about 200 nm.
7. The method according to claim 1 , wherein the low-frequency RF power is 0.44 W/cm 2 to 0.58 W/cm 2 , and the high-frequency RF power is 0.13 W/cm 2 to 0.27 W/cm 2 .
8. The method according to claim 7 , wherein the high-frequency RF power has a frequency of 13.56 MHz and the low-frequency RF power has a frequency of 430 kHz.