Abstract: In the process of fabrication of semiconductor devices, a lead frame hoop supplied from a supply reel is set forward to successively enter into a series of fabricating steps. After having been subjected to pellet bonding, wire bonding and resin-molding, it is wound up about a take-up reel. Baking step is performed with the lead frame hoop wound on the take-up reel. The lead frame hoop unwound from the take-up reel is cut into separate individual semiconductor device units from one another and the measurement of characteristics and the classification of the thus prepared units are carried out with the positions of the units maintained as they were at the cutting step. Accordingly, the process has a smaller number of steps and therefore the production cost is reduced, and the speed of working is improved.