Patent ID: 9371225
Filing Date: 2016-06-21
CPC Classification: B41J,B81B,B81C,H01L

Claim Text:
1. A substrate processing method for forming a through-hole in a substrate by reactive ion etching, the method comprising: preparing a substrate that has a first surface and a second surface and on the first surface side of which a first layer and a second layer are disposed, the second layer forming a side wall that covers a side surface of the first layer and a ceiling that covers an upper surface of the first layer; and performing reactive on etching on the substrate from the second surface to form a through-hole extending through the substrate from the first surface to the second surface, the reactive on etching being performed to reach the first layer; defining, as a vertical direction, a direction perpendicular to the first surface of the substrate, a length of the first layer in the vertical direction being 0.5 um or greater; and defining, as a horizontal direction, a direction parallel to the first surface of the substrate, the first layer having such a size that the first layer extends beyond an edge of the through-hole formed by a distance of 0.7 m or greater to each side in the horizontal direction. wherein the first layer is made of one of poly-Si and P—SiN, wherein an etching rate of the second layer for the reactive on etching is less than that of the first layer, and wherein the reactive on etching is performed to reach the ceiling of the second layer.