| 摘要 |
PROBLEM TO BE SOLVED: To provide a downsizable millimeter wave semiconductor device, having an electromagnetic sealed structure which displays good high frequency characteristics in an interior space sealed with a conductive cap to shield, is easily applicable to various packages for manufacturing various types of products because of a little high frequency characteristics change before and after the sealing, and does not need a long development time and a high cost. SOLUTION: A conductor formed on the surface of a seal cap 50 for sealing a millimeter device 30 mounted on a wiring board 10 has a ground potential. It is sealed so that the gap between the wiring board 10 and the inner surface of the seal cap 50 is less than a quarter wavelength of an applied frequency. This suppresses many waveguide modes at the applied frequency in the sealed space, whereby spurious electromagnetic waves propagating through this space can be lessened. |
