A circuit module containing a ceramic carrier substrate to carry
electronic parts, ceramic substrate pads provided on a surface of the
ceramic carrier substrate, and a lid having a cavity and a bottom surface
joined to the ceramic substrate pads with solder, the lid being a stepped
lid having protrusions adjacent to the cavity, and dents adjacent to the
cavity with the protrusions intervening therebetween, the protrusions
being in contact with the ceramic carrier substrate with a prescribed
distance to the ceramic substrate pads, and the dents being joined to the
ceramic substrate pads with solder.