A masking pattern is performed on a substrate by using materials that are
weakly adhered to the substrate, and then the masked substrate is etched.
Since the mask is weakly adhered to the substrate, the mask is peeled off
from the surface of the substrate, so that a gap is generated between the
mask and the substrate, and then anisotropic etching is performed.
According to this method, it is possible to easily manufacture an optical
measurement substrate having recesses whose sectional shape can be
approximated to a curve having inflection points. Therefore, optical
characteristics of a minute amount of substances can be evaluated
efficiently without the loss of incident and reflected light even when
measuring light is incident at an angle of less than 45 degrees.