The invention discloses a terahertz
broadband amplifier monolithic circuit which comprises an input matching network, the
signal input end of the input matching network is the
signal input end of the monolithic circuit, and the output end of the input matching network is connected with one input end of a first driving stage power amplification
transistor. One output end of the first driving stage power amplification
transistor is connected with the input end of the output stage power amplification
transistor through the first inter-stage matching network, and the output end of the output stage power amplification transistor is connected with the input end of the output matching network. The output end of the output matching network is the
signal output end of the single-
chip circuit; and the input matching network, the output matching network and the inter-stage matching network comprise
broadband tuning capacitors and are used for reducing the loss of the terahertz
broadband amplifier and improving the
gain and the output power of the broadband
amplifier. According to the monolithic circuit, the complexity of a THz broadband amplifier monolithic
integrated circuit can be reduced, the
circuit design period is shortened, and the size of the monolithic circuit is reduced.