NOVELTY - The apparatus has a main substrate holding unit that holds substrate in a processing chamber (12). A chemical solution supply unit (7) supplies the chemical solution containing the etching component and thickening agent to the substrate held by the main substrate holding unit. A substrate transfer unit transfers substrate from processing chamber (12) to another processing chamber in state in which chemical solution is held on the substrate. A sub substrate holding unit holds several substrates on each of which chemical solution is held in another processing chamber.    USE - Apparatus for processing substrate such as semiconductor wafer and glass substrate for LCD device. Can also be used in plasma display, field emission display, optical disk, magnetic disk, magneto-optical disk, photo-mask, ceramic substrates and solar cells.    ADVANTAGE - The substrate can be allowed to hold the chemical solution having high viscosity, hence the consumption of the chemical solution can be reduced. The foreign matters adhering to the substrate can be lifted off from the substrate along with the portion of the substrate by allowing the substrate and the chemical solution to react together and dissolving the portion of the substrate, hence the foreign matters can be reliably removed from the substrate. The chemical solution can be supplied to the subsequent substrate in the processing chamber during the progression of the reaction of the substrate and the chemical solution to each other, hence the decrease in the number of substrates to be processed per unit time can be prevented. The foreign matters in different processing chambers are measured by the foreign-matter measuring unit, hence the structure in each of the processing chambers can be restrained or prevented from being complicated.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for substrate processing method.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the chemical solution supply unit.    Chemical solution supply unit (7)    Chemical solution nozzle (9)    Nitrogen gas nozzle (11)    Processing chamber (12)    Gate shutter (22)