Patent ID: 7393791

Claim:
An etching method, comprising the steps of: preparing a substrate structure comprising a substrate, a to be etched film formed on the principal surface of said substrate, and an etching protection film formed on said to be etched film and having a hole formed therethrough; said hole being formed by an opening in the surface of said etching protection film and a hollow linked to said opening and reaching said to be etched film through said etching protection film; the planar shape of said opening being congruent to the planar shape of an etching-destined region of said to be etched film and a hole width of said hole widening toward said to be etched film in the depth direction from the surface of said etching protection film; and forming an exposure region in said principal surface of said substrate by removing, through inductively coupled plasma reactive ion etching under the following conditions, a to be etched film part existing in said etching-destined region of said to be etched film (1) ICP power has a value in the range of 20 to 100 W, (2) RIE power has a value in the range of 5 to 50 W, and (3) the pressure in an etching chamber has a value in the range of 1 to 100 mTorr.