Method for mfg. large power MOS tube with small wire wide slot type structure

The invention discloses a method for manufacturing small-linewidth grooved high-power MOS tube, adopting titanium alloy process to reduce the effect of contact hole injection on device characteristics and the contact resistance, and adopting chemical-mechanical polishing and leveling process to reduce the thermal process of B-P glass deposition and backflow so as to reduce the effect of the transverse diffusion of the contact hole injection on the device characteristics; and adopting W plug process to improve the burying property of a small-size contact hole. The invention can be used to semiconductor manufacturing.