To provide an electrodeposition mechanism of a resist film to a quartz wafer by a spray resist method, with which an electrodeposited resist can be formed with high accuracy.

In the electrodeposition mechanism, having a resist vessel for accommodating a resist liquid, a discharging nozzle for spraying the resist liquid in the form of mist and electrode needles for electrifying the resist liquid at the tip part of the discharging nozzle, a pressurizing gas is supplied to the resist vessel, an atomizing spray nozzle for sucking and spraying the liquid is provided, then heavy resist particles in the resist particles sprayed from the atomizing spray nozzle are allowed to fall on the resist liquid, and light particles in the resist particles sprayed from the nozzle are discharged from a flow-out port provided, at the upper part of the resist vessel and communicating with the discharge nozzle. Further, in the mechanism, a plurality of electrode needles are arranged in the outer periphery of the discharge nozzle at equal intervals.