Patent attributes
A semiconductor device is provided. In one example, a semiconductor device has a D-HBT structure which include a base layer formed from InGaAs and an emitter layer and a collector layer both formed from InGaP in such a way as to hold said base layer between them, wherein said InGaAs has a composition such that the content of In is smaller than 53% and said InGaP has a composition such that the content of In is just enough to make the lattice constant of said emitter layer and collector layer equal to the lattice constant of said base layer. This semiconductor device realizes a large current gain while keeping the high-speed operation owing to the base layer of InGaAs having good carrier mobility. In addition, it can be formed on a large wafer as the substrate.
