A semiconductor device includes a Si crystal having a crystal surface in the vicinity of a surface, and an insulation film formed on said crystal surface, at least a part of said insulation film comprising a Si oxide film containing Kr or a Si nitride film containing Ar or Kr. A slight rotation of a user’s blade holding tool changes a blade’s function from slitting to picking to hold-down modes with increased user safety with its restricted blade penetration and with fewer carpal tunnel stress motions required in its use. The assembly overcomes the drawbacks associated with filament lamps by using LED lamps that provide greater brightness with less power consumption. In this processing, a snapshot reference relation building processing part copies a file storage location management table, and relates the file storage location management table to the acquired snapshot. Otherwise, the second node propagates the message to other nodes.