| 摘要 |
PROBLEM TO BE SOLVED: To provide a processing method of a silicon substrate capable of suppressing the deterioration of reliability of a liquid injection head. ! SOLUTION: A processing method of a silicon substrate which includes a first liquid channel part 38 constituting a part of a liquid injection head for injecting liquid in a liquid channel and constituting a part of the liquid channel and a second liquid channel part 39 having a width wider than the first liquid channel part 38, communicated with the first liquid channel part 38, and is formed with a step part 40 between the first liquid channel part 38 and the second liquid channel part 39 includes: a first process for forming a first liquid channel part 38 by performing wet-etching up to the half in the plate thickness direction from the first surface side as (110) face of a silicon wafer 42 and a second process of forming the second liquid channel part 39 and the step part 40 by performing wet-etching from the second surface side of the opposite |
