Patent ID: 8758551

Claim:
A substrate processing apparatus comprising: a chamber that houses a disk-shaped substrate; a first electrode that is arranged in the chamber, the substrate being mounted on the first electrode; a second electrode constituting a shower head that is arranged such as to face the mounted substrate and has a number of penetrating gas holes, the second electrode has therein a space; a high-frequency power source that supplies high-frequency power between the first and second electrodes; a central vacancy that is comprised of a central portion of the space in the shower head; at least two annular buffer vacancies that are comprised of annular spaces formed outside the central vacancy and arranged sequentially in a radial direction of the shower head; a plurality of annular partition wall members that divide the space in the shower head with respect to the radial direction of the shower head such as to form the central vacancy and the at least two annular buffer vacancies; a plurality of pipes that are connected respectively to the central vacancy and the at least two annular buffer vacancies such as to supply processing gas and additional gas respectively to the central vacancy and the at least two annular buffer vacancies; and a branch flow rate adjusting apparatus that adjusts a flow rate of the processing gas which flow through each of the plurality of pipes; wherein each of the plurality of pipes is branched into at least two branched pipes, and the branched pipes are connected to each of the central vacancy and the at least two annular buffer vacancies via at least two connecting sections which are disposed on each of the central vacancy and the at least two annular buffer vacancies along a circumference of a circle arranged thereon at equal intervals, the at least two connecting sections belonging to each of the central vacancy and the at least two annular buffer vacancies are disposed symmetrically around the shower head center, regarding all the connecting sections of the plurality of pipes, one connecting section is shifted from another connecting section adjacent thereto at constant degrees in a rotational system centering around the center of the shower head, whereby a mixture of the processing gas and the additional gas is supplied symmetrically with respect to the center of the shower head and uniformly into the chamber so as to make uniform the distribution of an electric field generated in a processing space inside the chamber.