NOVELTY - The apparatus (1) has Lower speed rotation rinsing control unit that controls rotation unit and rinse liquid supplying unit so as to rotate substrate at lower rotation speed while supplying rinse liquid onto center portion of front surface of substrate. Entire surface rinsing control unit controls rotation unit and rinse liquid supplying unit so as to spread rinse liquid over entire front surface of substrate by rotating substrate at second liquid treatment rotation speed higher than lower rotation speed while supplying rinse liquid onto center portion of front surface of substrate.    USE - Apparatus for treating substrate such as semiconductor wafer, glass substrate for LCD device, substrate for plasma display device, substrate for field emission display (FED) device, substrate for optical disk, substrate for magnetic disk, substrate for magneto-optical disk, substrate for photo mask, ceramic substrate and substrates for solar cell with treatment liquid e.g. chemical liquid such as hydrofluoric acid, ammonia/hydrogen peroxide mixture, hydrochloric acid/hydrogen peroxide mixture, sulfuric acid/hydrogen peroxide (SPM) mixture and buffered hydrofluoric acid/ammonium fluoride (HF) mixture, for manufacturing semiconductor device and LCD device.    ADVANTAGE - The chemical liquid is replaced with the rinse liquid rapidly on the center portion of the front surface of the substrate, at lower replacement efficiency on the peripheral edge portion of the front surface of the substrate, by the selective supply of the rinse liquid. The rotation speed of the substrate is reduced, so that a very small centrifugal force or virtually no centrifugal force acts on the rinse liquid flowing over the front surface of the substrate. Thus reduces the temperature of the chemical liquid remaining on the peripheral edge portion of the front surface of the substrate, so as to reduce the treatment ability of the remaining chemical liquid. The etching liquid is replaced with the DIW rapidly on the center portion of the front surface of the wafer, at lower replacement efficiency on the peripheral edge portion of the front surface of the wafer, by supplying the DIW. Hence the etching liquid remains on the peripheral edge portion of the front surface of the wafer. The peripheral edge portion of the wafer is selectively etched with the remaining etching liquid. The chuck of the vacuum suction type rotates the wafer held in chuck. The etching treatment is evenly performed on the front surface of the wafer without prolonging the overall process time. Since rotation speed is reduced, and virtually no centrifugal force acts on the DIW on the front surface of the wafer, the DIW film covering the front surface of the wafer no longer spreads. Hence a relatively large DIW puddle is formed on the center portion of the front surface of the wafer. The delay period is determined so as to be necessary and sufficient for covering the entire center portion of the front surface of the wafer with the DIW supplied from the DIW nozzle. The peripheral edge portion of the wafer is selectively etched with the remaining etching liquid. Since the peripheral edge portion of the wafer is selectively etched with the remaining etching liquid in the DIW supplying step, the need to additionally perform the step of selectively etching the peripheral edge portion of the wafer is avoided. The higher temperature DIW valve for switching on and off the supply of the higher temperature DIW from the DIW nozzle is provided in the higher temperature DIW supply pipe. The temperature of the etching liquid remaining on the peripheral edge portion of the wafer is reduced, so as to reduce the etching ability of the etching liquid. The reduction in the temperature of the etching liquid remaining on the peripheral edge portion is suppressed. The etching liquid remaining on the front surface of the wafer is maintained at a higher temperature with the use of the higher temperature DIW, and thus obtains higher etching ability. The higher temperature rinse liquid is supplied onto the front surface of the substrate to suppress the temperature reduction of the chemical liquid remaining on the peripheral edge portion of the front surface of the substrate.?Thus the chemical liquid remaining on the peripheral edge portion of the front surface of the substrate exhibits higher treatment ability.    DESCRIPTION OF DRAWING(S) - The drawing shows a sectional view illustrating the construction of substrate treatment apparatus.    Apparatus for treating substrate (1)    Partition wall (2)    Treatment chamber (3)    Spin chuck (4)    Cup (7)