In a method in which a semiconductor wafer 1 having integrated circuits 3 formed in a plurality of chip regions and test patterns 4 formed in scribe lines 2a is divided by a plasma etching process so as to manufacture individual semiconductor chips, in the semiconductor wafer 1, a protection sheet 5 which constitutes a mask in the plasma etching process is adhered onto a front plane 1a thereof where the integrated circuits 3 have been formed; since laser light 9a is irradiated along the scribe lines 2a, only a predetermined width of the protection sheet 5 is removed so as to form a mask having a plasma dicing-purpose opening portion 5b; and also, the test patterns 4 are removed by the laser light 9a in combination with a front plane layer of the semiconductor wafer 1. As a result, the test patterns 4 can be removed in a higher efficiency and in simple steps, while the general purpose characteristic can be secured.