Patent ID: 6969629

Claim:
A method for manufacturing a micro-structural unit by performing machining on a material substrate which has a laminated structure comprising a first conductive layer, a second conductive layer, a third conductive layer, a first insulating layer interposed between the first conductive layer and the second conductive layer, and a second insulating layer interposed between the second conductive layer and the third conductive layer, the method comprising: a first etching step for performing an etching treatment on the first conductive layer to an intermediate point in a direction of thickness of the first conductive layer via a first mask pattern and a second mask pattern formed on the first conductive layer; a step for removing the second mask pattern; a second etching step for performing an etching treatment on the first conductive layer via the first mask pattern until the first insulating layer is reached, so that residual mask parts that contact the first insulating layer are left; a third etching step for performing an etching treatment via the residual mask parts on portions of the first insulating layer that are exposed in the second etching step until the second conductive layer is reached; and a fourth etching step for removing the residual mask parts by etching, and for performing an etching treatment on portions of the second conductive layer that are exposed in the third etching step.