Substrate processing method and substrate processing apparatus

1. A substrate processing method comprising:

storing a temperature of a peripheral edge portion of a substrate obtained by a preliminary experiment in a storage by a processor;

holding a substrate having a processing target surface and an opposite surface which is opposite to the processing target surface;

first ejecting a sulfuric acid hydrogen peroxide mixture (SPM) to a center portion of the opposite surface of the substrate to preheat the substrate;

acquiring a temperature of the preheated center portion of the substrate using a temperature sensor positioned above the substrate after the first ejecting;

determining a temperature difference between the temperature of the peripheral edge portion of the substrate stored in the storing and the temperature of the preheated center portion of the substrate acquired in the acquiring;

second ejecting the SPM to a peripheral edge portion of the processing target surface of the substrate when the temperature difference is 40° C. or less, after completing the first ejecting after the acquiring; and

moving an ejection position of the SPM in the second ejecting from the peripheral edge portion of the processing target surface to a center portion of the processing target surface of the substrate,

wherein the preliminary experiment includes ejecting the SPM to the peripheral edge portion of the substrate and measuring the temperature of the peripheral edge portion of the substrate.

2. The substrate processing method according to claim 1 , wherein the SPM ejected to the opposite surface of the substrate in the first ejecting is obtained by mixing sulfuric acid and hydrogen peroxide at a mixing ratio that causes a reaction temperature to be higher than the SPM ejected to the processing target surface in the second ejecting.

3. The substrate processing method according to claim 2 , further comprising:

changing the mixing ratio of the SPM ejected in the first ejecting to the opposite surface of the substrate according to a change of an SPM ejection position with respect to the processing target surface in the moving.

4. The substrate processing method according to claim 3 , wherein, in the first ejecting, a first SPM is ejected to the center portion of the opposite surface of the substrate, and a second SPM is ejected to a position of the substrate radially outside the center portion of the opposite surface.

5. The substrate processing method according to claim 1 , further comprising:

changing a mixing ratio of the SPM ejected in the second ejecting to the opposite surface of the substrate according to a change of an SPM ejection position with respect to the processing target surface in the moving.