摘要
In this paper,a new process to fabricate an electromagnetic stepping micromotor using surface scarificial layer technology(SSLT) is illustrated,and the SEM photo of the stepping micromotor is showed.The torque of the stepping micromotor with maxsimum torque of 60μNm is directly calculated by using electromagnetics laws and the law of conservation of energy.The stator and the shaft and the rotor of the micromotor with the material of nickel are first all fabricated by normal LIGA process at the same time.The sacrificial layer structure with the material of AZ resist is made on the surface of the rotor by using SSLT.The stator and the shaft are fixed together with copper substrate instead of the old Ti substrate by electroplating.After removing the Ti substrate,PMMA resist and the sacrificial layer structure,the rotor is separated from the stator and new copper substrate,and can rotate on the new substrate driven by magnetic force.The four coils with 300 turns each are wound on iron bars by hand using microscope and stepping motor.The bars are assembled by hand into the stator holes from rear of new copper substrate to from a magnetic circuit with the stator and the rotor.A power supply with four consecutive pulses provides the current for the coils wound on the iron bars adn produces the magnetic force to drive the rotor to run with the speed of 60 rpm.
