A Doherty amplifier, comprising: a metal baseplate having a die attach region and a peripheral region ; a main amplifier and one or more peaking amplifiers, wherein each amplifier comprises a transistor die attached to the die attach region , each transistor die including at least one RF terminal facing away from the baseplate ; a multilayer circuit board comprising: a first side attached to the peripheral region ; a second side facing away from the baseplate ; a first embedded electrically conductive layer that is separated from the second side by a first embedded composite fiber layer ; a second embedded electrically conductive layer that is separated from the first side by a second embedded composite fiber layer ; and an embedded dielectric layer that is disposed between the first and second embedded electrically conductive layers , and that has a higher dielectric constant than either of the first and second embedded composite fiber layers ; an RF impedance matching network that is electrically connected to an RF terminal of at least one of the amplifier transistor dies , and that comprises one or more reactive components (C1, L1) formed from at least one of the embedded electrically conductive layers. a metal baseplate having a die attach region and a peripheral region ; a main amplifier and one or more peaking amplifiers, wherein each amplifier comprises a transistor die attached to the die attach region , each transistor die including at least one RF terminal facing away from the baseplate ; a multilayer circuit board comprising: a first side attached to the peripheral region ; a second side facing away from the baseplate ; a first embedded electrically conductive layer that is separated from the second side by a first embedded composite fiber layer ; a second embedded electrically conductive layer that is separated from the first side by a second embedded composite fiber layer ; and an embedded dielectric layer that is disposed between the first and second embedded electrically conductive layers , and that has a higher dielectric constant than either of the first and second embedded composite fiber layers ; an RF impedance matching network that is electrically connected to an RF terminal of at least one of the amplifier transistor dies , and that comprises one or more reactive components (C1, L1) formed from at least one of the embedded electrically conductive layers. a first side attached to the peripheral region ; a second side facing away from the baseplate ; a first embedded electrically conductive layer that is separated from the second side by a first embedded composite fiber layer ; a second embedded electrically conductive layer that is separated from the first side by a second embedded composite fiber layer ; and an embedded dielectric layer that is disposed between the first and second embedded electrically conductive layers , and that has a higher dielectric constant than either of the first and second embedded composite fiber layers ; an RF impedance matching network that is electrically connected to an RF terminal of at least one of the amplifier transistor dies , and that comprises one or more reactive components (C1, L1) formed from at least one of the embedded electrically conductive layers. <EOS>