The ratio of the vertical dimension (height) to the horizontal
dimension (width) of a three-dimensional structure, used as an index to the relative thickness of
It is accepted that silicon process is not appropriate to form three-dimensional
structures of much depth, because it is difficult to manufactur structures
of an aspect ratio over 10:1. By the use of anisotropic etching or LIGA
process, deep holes, grooves and so on of an aspect ratio of 100:1 or greater
can be obtained.