| 摘要 |
PROBLEM TO BE SOLVED: To obtain a high frequency matching circuit board capable of transmitting power efficiently from an impedance of 50 Ω to the impedance of a semiconductor element, and to provide a high frequency matching circuit board and a microwave semiconductor device capable of achieving further compaction, while preventing increase in the number of components.SOLUTION: A high frequency matching circuit board 2 includes ceramic layers 3a-3e laminated downward in order. An impedance matching circuit 4a is provided on the upper surface of the ceramic layer 3a, and connected with the upper surface thereof. An impedance matching circuit 4b is provided between the ceramic layers 3b, 3c. An impedance matching circuit 4c is provided between the ceramic layers 3d, 3e. Ground patterns 6a-6c are provided just under the impedance matching circuits 4a-4c. The dielectric constant ε1 of the ceramic layer 3a is larger than the dielectric constant ε3 of the ceramic layer 3a, and the dielectric constant ε3 of the ceramic layer 3c is larger than the dielectric constant ε5 of the ceramic layer 3e.SELECTED DRAWING: Figure 1 |
