Provided is a modular pedicle screw assembly which includes various components that may be configured in various manners so as to provide different functionalities to the pedicle screw assembly. The roller brush, together with the hair remover, effectively clean and remove hair from styling combs and brushes and prevent accumulated hair from impeding the cleaning action by removing it from the roller brush. Further, a method for forming a bipolar semiconductor device is provided. The elastic component is disposed in the receiving groove. The ampoule has a surface formed with a groove extending along the circumferential direction thereof.