Patent ID: 7731861

Claim:
A manufacture method of a liquid drop discharge head including a head component chip formed by separation of a silicon wafer, the silicon wafer having a first direction and a second direction chat are mutually intersected, the method comprising the steps of: forming a slit at a T-shaped intersection between a lateral separation line and a lengthwise separation line of the silicon wafer, by utilizing alkali etching liquid, partially on a first separation line parallel to the first direction of the silicon wafer in order to partially separate the chip from the silicon wafer along the first separation line; chopper dicing a part of the silicon wafer which does not have a slit, by utilizing a dicing instrument, along the first separation line parallel to the first direction of the silicon wafer to form the first separation line along the first direction; and dicing the silicon wafer, by utilizing the dicing instrument, along a second separation line parallel to the second direction of the silicon wafer to completely separate the chip from the silicon wafer along the first and second separation lines, wherein the silicon wafer is of (110) crystalline orientation, and a plurality of chips, configured in a rectangular formation, are arranged in the silicon wafer, and first separation lines for the plurality of chips to be separated from the silicon wafer by the etching step are parallel to <112> orientation of the silicon wafer, and wherein perpendicular (111) to a wafer side is formed by pattern of the <112> orientations.