PURPOSE: To prevent a concentration of the current in a bending portion and obtain a protective layer without break-down by a method wherein Si layer is provided on an insulation basic body or a reverse conduction type diffusion layer is provided on a reverse conduction type semiconductor to form a linear high resistor and they are connected through a low resistor layer by bending them alternately.

CONSTITUTION: A protective resistor 12 consisting of polysilicon material is formed on an insulation film 11 of Si substrate, the vertical linear portions 121, 122 ... are parallel-arranged in parallel with each other, while they are connected with the lateral linear portions 123, 124 ... and the full configuration is formed in a bending shape. The end of the linear portion 129 is connected in seies with the IC input part of the Si substrate and the end of the linear portion 121 is connected through a hole 13 in the insulation film 11 to an electrode pad 13. A small hole is provided in the crossed portion of the vertical or lateral line, that is, each bending portion of the protective resistor to charge Al141∼148 thereinto. According to such a constitution, if the excessive input is applied from the pad 13, since the bending portions are made of Al of low resistance, the portions are protected from break-down by avoiding the current concentration. Therefore, the protective resistor of longer size and higher resistance value can be obtained without exerting any adverse influence against an integrated density by increasing a turning number of the bending.