A semiconductor package includes a substrate, a semiconductor chip disposed on the substrate, and a connection wiring connected electrically to the semiconductor chip. Since a tumor-targeting gas-generating nanoparticle according to the present disclosure is accumulated in the tumor tissue in large quantity and generates strong ultrasound wave signals, it can be usefully used as a contrast agent for ultrasonic imaging. The spring clamp may include a head piece with a greater thickness than the other parts of the spring clamp to provide greater material strength at a point of contact between the spring clamp and an air filter housing. C) heating the sealed device to a gas-expelling temperature for expelling the target gas from the leak in the sealed optical device.