In order to imprint wafer-identifying information on a wafer on which a
plurality of thin-film devices are formed in a batch, utilizing a
patterned resist layer, an exposure apparatus exposes a resist layer
formed on the wafer to light for forming a latent image of the
wafer-identifying information. The exposure apparatus allows a mask
storage controller and a mask transfer device to select a mask, on which
the pattern of a numeral or symbol to be imprinted is drawn, for each
digit of the wafer-identifying information and carries out exposure. The
exposure apparatus also allows a mask shift controller to change the
positional relationship between the wafer and the mask for each digit of
the wafer-identifying information so that the numeral or symbol of each
digit of the wafer-identifying information is imprinted at a mutually
different position.
