MULTILAYER STRIP LINE

PROBLEM TO BE SOLVED: To suppress the deterioration of a characteristic of a combined line composed by using lines of an upper layer and a lower layer even if the upper layer and the lower layer of a multilayer substrate are deviated from each other.SOLUTION: At a triplate line 8 formed on a third-layer wiring layer 3 and a triplate line 9 formed on a fourth-layer wiring layer 4, a combining line 111 of a length of 1/4 of an input signal wavelength λg is formed. If a deviation amount between the third-layer wiring layer 3 and the fourth-layer wiring layer 4 is assumed to be A1, widths W1 and W2 of the triplate lines 8 and 9 are set to satisfy W1-W2 ≥ A1.