Improved endpoint detection is obtained for wet etch andor other chemical processes involving in situ measurement of bath impedance. The cover member is detachably attached to the case main body by a lock mechanism disposed between the case main body and the cover member. The virtual platform layer may include services and resources for supporting the zones, which can be made accessible to the zones in the form of a virtual platform. The logic is further configured to receive a second user input selecting one of the function identifiers and to transmit a remote procedure call through the wireless network to the one node in response to the second user input. It is desirable that a has the smallest value which achieves that. The method includes forming a deep STI region adjacent to a first side of an end fin among a plurality of fins and lining the deep STI region, including the first side of the end fin, with a passivation layer.