Method of manufacturing semiconductor device
A method of manufacturing a semiconductor device comprises forming a contact hole within an interlayer insulating film of a substrate and forming a contact plug while the substrate is heated. In forming the contact plug, the substrate is held on a stage within the chamber of a sputtering apparatus through a chuck, and an ESC voltage applied to the chuck is increased stepwise in a plurality of steps. First target power is applied to a target within the chamber to form a first Al film in the contact hole. Next, second target power higher than the first target power is applied to the target within the chamber to form a second Al film on the first Al film.
1. A method comprising:
performing steps (1)-(3) in order while a substrate is heated, to form a first film comprising second and third films over the substrate, each of the second and third films containing at least aluminum:
(1) holding the substrate on a stage in a chamber of a sputtering apparatus through a chuck and increasing a voltage applied to the chuck stepwise in a plurality of steps;
(2) applying a first target power to a target in the chamber, to form the second film over the substrate; and
(3) applying a second target power to the target in the chamber, to form the third film on the second film.
2. The method according to claim 1 , wherein the substrate comprises a semiconductor substrate.
3. The method according to claim 1 , wherein in the step (3), the second target power is higher than the first target power.
4. The method according to claim 1 , wherein in the step (1), the plurality of steps include a first step and a final step following the first step, and the voltage in the first step is one half or less of the voltage in the final step.
5. The method according to claim 1 , wherein in the step (1), the plurality of steps include an (n−1)th step and an (n)th step following the (n−1)th step, the voltage applied to the chuck being a first voltage in the (n−1)th step, the voltage applied to the chuck being a second voltage in the (n)th step, the second voltage being in the range of double from one time of the first voltage, where n is a natural number greater than 1.
6. The method according to claim 1 , wherein in the step (3), the second target power is four or more times as large as the first target power.
7. The method according to claim 1 , wherein in the step (3), a film-forming rate of the third film is larger than a film-forming rate of the second film.
8. The method according to claim 1 , wherein in the steps (1) to (3), the substrate is heated at 400° C. or more.
9. The method according to claim 4 , wherein in the steps (1), a noble gas for controlling a substrate temperature is supplied to a back side surface of the substrate after the voltage applied to the chuck has reached the voltage in the final step.