Abstract: A power supply unit supplies power to a load, and the power supply unit includes a power factor corrector, a DC conversion module, and an isolated conversion module. The power factor corrector is plugged into a first main circuit board and converts an AC power into a DC power. The DC conversion module is plugged into the first main circuit board and converts the DC power into a main power. The isolated conversion module includes a bus capacitor, the bus capacitor is coupled to the DC conversion module through a first power copper bar, and coupled to the power factor corrector through a second power copper bar. The first power copper bar and the second power copper bar are arranged on a side opposite to the first main circuit board, and are arranged in parallel with the first main circuit board.

Abstract: A method for forming a semiconductor device structure is provided. The method includes providing a wafer over a polishing platen. The wafer includes a metal layer and a dielectric layer. The metal layer covers the dielectric layer and fills an opening of the dielectric layer. The method also includes polishing the wafer using a first operation to thin down the metal layer. The first operation has a first polishing selectivity of the metal layer to the dielectric layer. The method further includes polishing the wafer using a second operation to further thin down the metal layer until the dielectric layer is exposed. The second operation has a second polishing selectivity of the metal layer to the dielectric layer. The second polishing selectivity is different from the first polishing selectivity. The first operation and the second operation are performed in-situ on the polishing platen.

Abstract: A method for forming a semiconductor device structure is provided. The method includes providing a wafer over a polishing platen. The wafer includes a metal layer and a dielectric layer. The metal layer covers the dielectric layer and fills an opening of the dielectric layer. The method also includes polishing the wafer using a first operation to thin down the metal layer. The first operation has a first polishing selectivity of the metal layer to the dielectric layer. The method further includes polishing the wafer using a second operation to further thin down the metal layer until the dielectric layer is exposed. The second operation has a second polishing selectivity of the metal layer to the dielectric layer. The second polishing selectivity is different from the first polishing selectivity. The first operation and the second operation are performed in-situ on the polishing platen.