A cleaning effect is improved by cleaning a component that has a recess
structure by using a cleaning medium of a liquefied gas or a
supercritical fluid. By the cleaning method of removing adhering
substances adhering to at least the surface of the recess structure of
the component that has the recess structure, cleaning is carried out by
using the supercritical gas or the liquefied gas so that the cleaning
medium spreads over the surface of the recess structure.