Production of condensed water in an intercooler is suppressed. A drain hose may be attached to a spout portion of the funnel, the filter is punctured, and oil allowed to drain therefrom. The arrangement information generation unit is configured to generate second arrangement information in which the first arrangement information is corrected based on the nozzle information. A portion of the field plate layer is removed to expose a first portion of the emitter surface. In the case of using phosphorus, its implantation energy is set to, for example, 60 to 120 keV, and the density of the channel stop layer is set to 1\xd71017 to 1\xd71019cm3.